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[Display omitted] • Paper mill sludge ash (pm SA) was used as catalysts to activate PMS. • Aerobic calcination was conducive to the exposure/formation of octahedral FeIII. • The O O bond fracture was the root pathway for FeIV O production. • The release of solid calcium in pm SA could inhibit the active decay of FeIV O. • The pm SA could effectively degrade similar pollutants in near-neutral water. The excellent performance of high-valent iron-oxo species (FeIV O) in the degradation of pollutants by activating peroxymonosulfate (PMS) had attracted much attention. However, the generation and reaction mechanisms were still unclear. In this study, iron-rich paper mill sludge was used as a raw material for the first time to prepare iron-based catalysts with abundant octahedral FeIII sites (Fe oct III). The results showed that the highest content of Fe oct III was found in the paper mill sludge ash obtained by aerobic calcination at 800 °C (pm SA800), and the pm SA800 could exhibit excellent catalytic activity (0.4785 min−1) and stability during the oxytetracycline (OTC) degradation process. The characterization and density functional theory (DFT) calculations further indicated that the Fe oct III was the dominant active site for FeIV O production. PMS tended to be adsorbed on two adjacent Fe oct III sites to form a [Fe oct III-OSO 2 OO(H)-Fe oct III] complex with a two-site adsorption configuration. Subsequently, the O O and O H bonds in [Fe oct III-OSO 2 OO(H)-Fe oct III] broken by absorbing energy, generating FeIV O. It's worth noting that the Ca species of pm SA800 effectively stabilized the pH of the reaction solution, which ensured the stable and continuous production of FeIV O. This work provides a new idea and insight for preparing catalysts that could produce FeIV O active species. [ABSTRACT FROM AUTHOR]

Given its superior structure, the abundance of surface functional groups, and low cost, cotton fiber filtration paper can be used as the support for hydrogen evolution reaction (HER) and oxygen evolution reaction catalysts (OER) instead of copper foam (CF), nickel foam (NF), or carbon cloth (CC). Herein, the chemical plating method was used to create thin self-supporting electrodes based on cotton fiber filtration paper (FP). The Co-Ni-P amorphous nanospheres can be uniformly dispersed on the self-supporting FP due to its porous structure and oxygen functional groups. The Co-Ni-P/FP electrode has an overpotential as low as 125 mV for HER and 320 mV for OER at the current density of 10 mA cm−2. Additionally, according to density functional theory (DFT) calculations, the Co atom added to the Ni-P nanosphere can lead to considerably more charge accumulation around the Co and Ni active sites, which greatly encourages the HER and OER processes. The novel porous support, FP, provides a fresh way the preparation of self-supporting electrodes. [Display omitted] • Filter paper is used to prepare the self-supporting electrode as the substrate. • The preparation method is simple and the properties are stable. • Rich oxygen-containing functional groups of FP promote deposition and dispersion. • Explore the excellent electrochemical performance of amorphous Co-Ni-P/FP by DFT. [ABSTRACT FROM AUTHOR]

The waste cooking oil is upcycled into N-doped carbon nanosheets, enabling fast Na+/K+ storage by means of surface charge modulation. [Display omitted] • Waste cooking oil was selected as precursor to prepare hard carbon anode materials. • NWCOC650 takes on a porous nanosheet structure with turbo layers. • NWCOC650 has a coexistence storage mechanism of adsorption/intercalation-filling. • Head group (–NH 2) can produce a synergistic effect with N-5/6/Q and graphene. • NWCOC650 exhibits excellent performances for sodium/potassium-ion batteries. Hard carbons are significant in sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). However, the structural defects of hard carbons lead to poor rate performance and cycling stability, which need further improvement. The waste cooking oil was used as the precursor to synthesize 3D carbon nanosheets (NWCOC) with amino nitrogen functional groups, multi-layered pores, and expanded interlayer spacing. The excellent electrochemical properties of NWCOC were investigated and it was demonstrated that NWCOC can significantly improve the adsorption of Na+/K+ on hard carbons, substantially enhancing the embedding/de-embedding of Na+/K+, reducing the diffusion distance of ions and electrons, and improving their adaptability to volume changes. In situ XRD and Raman characterization reveal that the Na storage mechanism of NWCOC is mainly based on adsorption/intercalation-filling. Combined with density functional theory, it is shown that the porous structures doped with nitrogen have a greater propensity for ion adsorption, resulting in increased ion capture and storage. As expected, NWCOC650 exhibits high capacities of 489.4 and 388.3 mAh/g in SIBs and PIBs. NWCOC650 displays superior performance in the Na 3 V 2 (PO 4) 3 /NWCOC650 full cell, achieving a capacity of 107.84 mAh/g. This work presents a new perspective on the synthesis and mechanisms of high-performance anodes for SIBs and PIBs. [ABSTRACT FROM AUTHOR]

The synergistic effect between metals is of great significance for improving the performance of materials, but the mechanism of synergistic catalytic of bimetallic has rarely been reported in the hydrolysis of sodium borohydride (NaBH 4 , SB). In this paper, a flower shaped Co 2 FeO 4 catalyst with high catalytic performance was selected from a series of Co x M 3-x O 4 (M = Fe, Ni, Cu) catalysts by controlling the composition. Based on the results of XPS characterization and density functional theory (DFT) calculation, the influence of component control on catalytic performance was discussed and explained from the perspective of electronic structure, and the "valence band center" and "D-band center" descriptors were introduced into the SB hydrolysis reaction. The simulation analysis results showed that the synergistic effect between Co–Fe elements resulted in the smallest center shift of the D band, the smallest binding energy of the hydrolysis reaction, and the best promoting effect on the electronic structure, manifested as the best catalytic performance. The calculation results were consistent with the XPS characterization results and the experimental results of hydrolysis performance testing, revealing the principle of bimetallic synergistic effect on catalytic performance. The synergistic effect between metals is of great significance for improving the performance of materials, but the mechanism of synergistic catalytic of bimetallic has rarely been reported in the hydrolysis of sodium borohydride (NaBH 4 , SB). In this paper, a flower shaped Co 2 FeO 4 catalyst with high catalytic performance was selected from a series of Co x M 3-x O 4 (M = Fe, Ni, Cu) catalysts by controlling the composition. Based on the results of XPS characterization and density functional theory (DFT) calculation, the influence of component control on catalytic performance was discussed and explained from the perspective of electronic structure, and the "valence band center" and "D-band center" descriptors were introduced into the SB hydrolysis reaction. The simulation analysis results showed that the synergistic effect between Co–Fe elements resulted in the smallest center shift of the D band, the smallest binding energy of the hydrolysis reaction, and the best promoting effect on the electronic structure, manifested as the best catalytic performance. The calculation results were consistent with the XPS characterization results and the experimental results of hydrolysis performance testing, revealing the principle of bimetallic synergistic effect on catalytic performance. [Display omitted] • Flower-like Co 2 FeO 4 showed the best catalytic performance. • The "D-band center" and "valence -band center" of Co 2 MO 4 were studied. • Composition and electronic control improve the catalytic performance of Co 2 MO 4. • The adsorption configuration of H 2 O on the Co 2 MO 4 (311) surface was studied. [ABSTRACT FROM AUTHOR]

Compared with traditional water electrolysis, electrolysis of seawater has larger resources and a brighter future. However, seawater contains more elements that have greater corrosive effects on electrodes; especially chloride ions (seawater contains more chloride ions) have the greatest impact. The existence of the corrosion problem creates greater difficulties in electrolyzing seawater, further limiting the efficiency of the electrocatalyst for electrolysis of seawater. In this paper, we report a Mn-doped Ni 2 P/Cu 3 P as an environmentally friendly monofunctional electrode for seawater electrolysis, which was made by a simple hydrothermal phosphatization operation method. The experimental results show that Mn-doped Ni 2 P/Cu 3 P presents overpotential of only 161 mV for oxygen evolution reaction (OER) at iR compensation of 90 and a current density of 10 mA cm−2. It has a small Tafel slope (25.15 mV dec−1) and a large capacitance (9.58 mF cm−2 on 1 × 1 nickel foam), which exceeds most reported oxygen evolution activities of non-precious metal-based electrocatalysts for electrolysis of alkaline seawater. The performance of Ni 2 P/Cu 3 P was probably significantly enhanced due to Mn doping by some characterization means. Through Density functional theory (DFT) analysis, it is known that the doping of Mn gives a large enhancement in the adsorption energy of water when Ni 2 P/Cu 3 P is electrolyzed with seawater. This paper provides train of thought for the exploration of excellent electrocatalysts for electrolysis of alkaline seawater. The experimental results show that Mn-dopedNi 2 P/Cu 3 P present overpotential of only 161 mV at i-R compensation of 90 for oxygen evolution reaction in alkaline seawater. [Display omitted] • Mn-doped Ni 2 P/Cu 3 P electrodes was synthesized for the first time through hydrothermal processes. • The overpotential of Mn-doped Ni 2 P/Cu 3 P electrode is only 161 mV at 10 mA cm−2 for OER. • The doping of Mn gives a large enhancement in the adsorption energy of water. [ABSTRACT FROM AUTHOR]

Electrolysis of water for production of hydrogen has become one of the most fascinating methods to relieve the energy crisis and environmental pollution. In this paper, a series of M-NiS/Mo 2 S 3 (M = Co, Fe, Ce and Bi) materials was in situ grown on Ni foam through a two-step hydrothermal process, and the synthesized Co–NiS/Mo 2 S 3 material present excellent hydrogen evolution reaction (HER) properties. Under an alkaline condition of 1 M KOH, Co–NiS/Mo 2 S 3 requires only overpotential of 142 mV to achieve a current density of 10 mA cm−2, and using Co–NiS/Mo 2 S 3 as both cathode and anode, only the potential of 1.574 V is required to drive a current density of 50 mA cm−2, with a relatively good durability over 15 h. Density functional theory (DFT) analysis show that the ΔG H* of Co–NiS is closer to 0 and its density of states near the Fermi energy level is higher, suggesting that Co–NiS improves the electrical conductivity of Co–NiS/Mo 2 S 3 and plays a significant catalytic action. This work proposes novel insights for the future exploration of novel sulfur-based composite electrocatalysts with excellent HER performance. In this paper, a series of M-NiS/Mo 2 S 3 (M = Co, Fe, Ce and Bi) materials was in situ grown on Ni foam by a two-step hydrothermal method, and the synthesized Co–NiS/Mo 2 S 3 material present excellent hydrogen evolution reaction (HER) properties. [Display omitted] • M-NiS/Mo 2 S 3 (M = Co, Fe, Ce and Bi) materials were successfully synthesized by hydrothermal processes. • Co–NiS/Mo 2 S 3 electrode shows excellent catalysis in the cathode reaction of water and water electrolysis. • Co–NiS/Mo 2 S 3 requires only overpotential of 142 mV to achieve a current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is considered as a green and efficient way of hydrogen production. How to promote the performance of electrode and develop stable non-precious metal catalysts has caused extensive research. One of the effective strategies is combining two or more catalytic materials to build heterogeneous structures. In this paper, a series of Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 heterostructured materials were synthesized to in-situ grow Ni 3 S 2 /Ni 3 Sn 2 S 2 on Ni foam with a 3D porous structure by modulating the substance ratio of elemental cobalt and elemental sulfur through a one-step hydrothermal process. The materials have superior oxygen evolution reaction (OER) properties and urea oxidation reaction (UOR) performance. Under an alkaline electrolyte of 1 M KOH, for OER, Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 only requires overpotential of 251 mV to obtain a current density of 10 mA cm−2. In an alkaline solution of 1 M KOH +0.5 M urea, for UOR, only the potential of 1.326 V was demanded for the catalyst to reach a current density of 50 mA cm−2, but its stability over 15 h was average. Density Functional Theory (DFT) analyses suggest that Co–Ni 3 S 2 has better metallic properties and promote the dynamics in catalysis. This study put forward a new thought for future research on nickel-tin binary metal sulfide hybrid electrocatalysts with excellent freshwater, seawater and urea oxidation properties. In this paper, a series of Co x -Ni 3 S 2 /Ni 3 Sn 2 S 2 materials was in situ grown on Ni foam by a one-step hydrothermal method, and the synthesized Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 material present excellent water and urea oxidation properties. [Display omitted] • Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 materials were successfully synthesized by hydrothermal processes. • Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 electrode shows excellent catalysis in the cathode reaction of water and urea. • Co 0.3 -Ni 3 S 2 /Ni 3 Sn 2 S 2 requires only potential of 1.326 V to achieve a current density of 50 mA cm−2 for UOR. [ABSTRACT FROM AUTHOR]

Using the WIEN2k code, first-principles simulations of ZrXH 3 (X = Zn, Cd) hydride perovskites are performed to determine their hydrogen storage properties. The purpose of this study is to investigate their structural, optoelectronic, hydrogen storage, mechanical and thermoelectric properties. The structural analysis demonstrates their stability through the heat of formation along with desorption temperature and shows that these compositions belong to the orthorhombic space group Cmcm (no.63). The band structure and density of states are estimated for electronic characteristics, indicating the metallic nature of both compositions. Analysis of elastic properties such as elastic constants, Pugh's ratio, bulk modulus, Poisson's ratio, and anisotropy factor are explored to determine the mechanical stability of these compositions and demonstrate their suitability as a transport medium in hydrogen storage systems even at higher pressure. To study the optical behavior of the perovskites under consideration for hydrogen storage applications, the dielectric parameters, dielectric constants, refractive index, optical conductivity, absorptivity, and energy loss function are studied. The present paper represents the initial theoretical effort toward future exploration of these materials for hydrogen storage applications. [Display omitted] Using the WIEN2k code, first-principles simulations of ZrXH 3 (X = Zn, Cd) hydride perovskites are performed to determine their hydrogen storage properties. The purpose of this study is to investigate their structural, optoelectronic, hydrogen storage, mechanical and thermoelectric properties. The structural analysis demonstrates their stability through the heat of formation along with desorption temperature and shows that these compositions belong to the orthorhombic space group Cmcm (no.63). The band structure and density of states are estimated for electronic characteristics, indicating the metallic nature of both compositions. Analysis of elastic properties such as elastic constants, Pugh's ratio, bulk modulus, Poisson's ratio, and anisotropy factor are explored to determine the mechanical stability of these compositions and demonstrate their suitability as a transport medium in hydrogen storage systems even at higher pressure. To study the optical behavior of the perovskites under consideration for hydrogen storage applications, the dielectric parameters, dielectric constants, refractive index, optical conductivity, absorptivity, and energy loss function are studied. The present paper represents the initial theoretical effort toward future exploration of these materials for hydrogen storage applications. • Stability of ZrXH 3 (X = Zn, Cd) hydride perovskites is confirmed by Enthalpy of formation. • ZrXH 3 (X = Zn, Cd) hydride perovskites have high value of decomposition temperature. • The gravimetric hydrogen storage capacities comes out to be 1.89 % and 1.46 % respectively. • Metallic behavior is reveled by electronic structure of these hydrides. [ABSTRACT FROM AUTHOR]

Hydrogen energy is one of promising non-polluting and renewable energy sources. In this paper, we present a first principal study of hydrogen storage in pure C 60 fullerene cage and Stone-Wales (SW) defective C 60 cages using density functional theory (DFT) with applying both the exchange functional B3LYP and the dispersion correction wb97xd at 6–31+g(d,2p) basis set. In addition, the counterpoise correction is applied, and the basis set superposition error is calculated. The calculations underscore that the hydrogenation binding energy of C 60 cages occurs through an endothermal process for C 60 H in with a hydrogen binding energy of 0.09 eV and through an exothermal process for C 60 H out , C 60 SW 66 H out , and C 60 SW 65 H out , cages with hydrogen binding energies of −2.17 eV, −2.96 eV, and −2.20 eV, respectively. Remarkably, for the first time, the intermediate hydrogen binding energy is found inside C 60 SW 66 H in fullerene, and C 60 SW 65 H in fullerene cages with energies of −0.26 eV and −0.81 eV, respectively. The hydrogen adsorption inside the cavity of C 60 SW 66 fullerene cage is thermodynamically possible below 289.8 K and entire pressure range considered. Our results highlight, for the first time, that the endohedral cavity of C 60 SW 66 is a promising new medium for hydrogen storage due to its binding energies (−0.26 eV) and its hydrogen storage weight percentage (5.3%) that are close to the optimal conditions specified by DOE for commercial use. In addition, this study opens up a new discovery of Stone-Wales defective C 60 fullerene for further endohedral cavity applications. • New insight into endohedral cavity of Stone Wales C 60 SW 66 is reported. • For the first time, a new promising medium for hydrogen storage inside cavity of C 60 SW 66 is proved. • Binding energies of −0.26 eV and hydrogen storage weight percentage up to 5.3% are achieved inside the cavity of C 60 SW 66. • This study opens a new discovery of the SW defective C 60 fullerene for further endohedral cavity applications. [ABSTRACT FROM AUTHOR]

The distribution of stable isotopes in organic compounds within geochemical systems reflects the reactions they undergo, which are often kinetically governed and can be elucidated through quantification based on first principles: employing quantum chemical simulations to derive energy barriers and kinetic isotope effects (KIEs), followed by kinetic calculations using these parameters. In this paper, the distribution of 13C in hydrocarbon gases during the thermal generation and decomposition of ethane and propane has been addressed. The work is based on abundant and systematic isotopic data, including the compound- and position-specific 13C compositions, recent improvements in kinetic networks in hydrocarbon generation, and state-of-the-art quantum chemical methods that can process organic geochemical systems involving solid phases. Density Functional Theory computations validate the carbonium path of hydrocarbon generation and the free-radical path of their decomposition under geological conditions. The first step of each path (alkyl sidechain protonation for generation and hydrogen abstraction for decomposition) is the rate-limiting step and determines the 13C fractionations of gaseous hydrocarbons, with the reaction rate constrained by the concentration or accessibility of the active species (hydrated protons and surface free radicals in the two paths, respectively). Alkyl protonation has normal 13C KIEs, but hydrogen abstraction on the surfaces of solid organic matter has inverse ones (substituting 12C by 13C accelerates the reaction). These inverse KIEs explain three isotopic phenomena in gaseous hydrocarbons in their late thermal evolution: 1) the depletion of 13C in ethane and propane accompanied by their decreased fraction in hydrocarbon gases (isotope "rollover"); 2) the reversed 13C sequence with carbon number (δ13C methane > δ13C ethane > δ13C propane); and 3) the depletion of 13C in the center carbon atoms of residual propane. Isotopic fractionation between gaseous hydrocarbons upon generation is evaluated using the Successive Random Chain-Scission model. The covariation of δ13C in alkanes shows a depletion in CH 4 compared with the values expected from the reciprocal of the carbon numbers, indicating that this deviation may be intrinsic instead of mixing with microbial methane. The comparison of intramolecular 13C fractionation of propane between computational and observed data suggests the contribution of isoprenoids at the beginning of the generation, in addition to isotopic homogenization between the center and end carbon atoms through the ring closure of intermediate cations. The 13C–13C clumping exhibits a weak KIE in both the generation and decomposition of ethane; the clumping is essentially stochastically governed. This work demonstrates how first-principle calculations can provide significant insights into the details of geochemical reactions governing the isotopic distributions. [ABSTRACT FROM AUTHOR]

In this paper, a new design principle for bimetallic catalysts is proposed by combining strongly adsorbed atoms (SAA) with weakly adsorbed atoms (WAA) where the SAA and WAA are classified by the free adsorption energy of oxygen-containing intermediates on the metal atom. And the ORR performances of the bimetallic catalysts designed by the method are compared with the common single metal atom catalysts. The method is successfully confirmed as the overpotential of the Mn-based bimetallic catalysts decreases from 0.63 V in G-MnN 4 to as low as 0.33 V, and that of the Fe-based bimetallic catalysts decreases from 0.76 V in G-FeN 4 to 0.23 V. In addition, the correlation between adsorption free energy and adsorption bond length is revealed for the first time, and the optimal adsorption bond length is determined. Finally, the adsorption energy of O 2 is plotted versus the free adsorption energy of three oxygen-containing intermediates for the first time, and a suitable adsorption energy of O 2 is found to be -1.4∼-1.0 eV. These findings provide a new perspective for the design of high-performance bimetallic catalysts. • Catalysts obtained by combining strongly adsorbed atoms with weakly adsorbed atoms show superior performance. • Correlation between adsorption free energy and adsorption bond length is revealed for the first time. • Adsorption energy of O 2 can be used as a descriptor of ORR performance. • ORR performance is related to the energy difference of hybridization between metal atom and adsorbed species. [ABSTRACT FROM AUTHOR]

The efficient hydrogen-production through the Aluminum-water reaction has become a prominent subject of interest. The impediment encountered in the reaction can be effectively alleviated by Aluminum-based alloy. In this study, density functional theory (DFT) was utilized to explore the mechanism of water decomposition stage on the surface of aluminum and gallium alloy (AGA). Through surface reaction calculations of 12 stable AGA configurations, it was gradually revealed that the optimal alloy ratio was gallium-to-aluminum at 3.5:1. Analysis of the density of states (DOS) indicated that the presence of gallium amplified the activity of surface aluminum. Moreover, frontier orbital theory and charge density maps confirmed that, due to the weak interaction between Ga and ions, the presence of H 2 inhibited Ga passivation, thereby enhancing the reactivity of AGA. This paper provided valuable insights into the surface reaction mechanisms of AGA using DFT, offering theoretical support for hydrogen production processes. • Density functional theory investigated the early stages of AGA-water reaction. • Modeling AGA (Ga proportions 73.8%–81.2%) yields 12 stable configurations. • Ga:Al = 3.5:1 exhibits highest energies for O 2 , H 2 O, and co-adsorption. • Ga enhances AGA's catalytic activity, shown in DOS graphs comparisons. • AGA plays dual roles in surface hydrogen dynamics. [ABSTRACT FROM AUTHOR]

The novel S-scheme heterostructure shows its superiority in photocatalysis due to its high efficiency of charge transfer. In this paper, we compared the mechanical, electronic, optical and transport properties of two different contact modes of heterostructure structures of MoSe 2 /Janus PtSSe and their applications in photocatalytic water splitting through density functional theory. The results show that the charge transfer of MoSe 2 /SePtS heterostructures occurs between layers. On the contrary, the charge separation of MoSe 2 /SPtSe heterostructures is significant, and there are internal electric fields and suitable band arrangements at the interface from MoSe 2 to SPtSe direction, forming S-scheme photocatalysts. Compared with the MoSe 2 /SePtS heterostructure, the MoSe 2 /SPtSe heterostructure has higher carrier mobility. Furthermore, the MoSe 2 /SPtSe heterostructure has good light absorption in the visible range, and the solar-to-hydrogen (STH) efficiency is as high as 7.97%. Gibbs free energy calculation shows that the overpotential η OER = 1.63 V (pH = 0) decreases to η OER = 1.11 V(pH = 7) with the increase of pH value. We expect that our results can provide valuable insights into the rational design of efficient heterostructure in photocatalytic water splitting systems. [Display omitted] • MoSe 2 /SPtSe heterostructure with high carrier mobility. • The existence of charge transfer in the MoSe 2 /SPtSe heterostructure is advantageous. • MoSe 2 /SPtSe heterostructure is a S-scheme photocatalyst for water splitting. • The ηOER of MoSe 2 /SPtSe heterojunction decreased with the increase of pH. • MoSe 2 /SPtSe heterostructure has ultra-high STH efficiency (7.79%). [ABSTRACT FROM AUTHOR]

In this paper, based on the first-principle calculations of hybrid density functional theory, the MoSTe/g-GeC of the Z-scheme heterostructure is constructed. The stability, electronic properties, optical absorption properties, and photocatalytic mechanism of the heterostructure is investigated. The band structure of MoSTe/g-GeC heterostructure is staggered, and the bandgap is 0.47 eV. The built-in electric field from g-GeC to MoSTe, with a size of 1.03 eV. The optical absorption coefficient of MoSTe/g-GeC heterostructures is significantly higher than that of MoSTe and g-GeC layer. When pH ranges from 0 to 7, the reduction reaction occurs in g-GeC layer, and the oxidation reaction occurs in the MoSTe layer. In the MoSTe/g-GeC heterostructure under different stresses, the band structure is arranged in a staggered manner. Importantly, under tensile strain, the bandgap of MoSTe/g-GeC heterostructure can be changed from the indirect into a direct bandgap. The bandgap of heterostructure decreases under the strain. In addition, the analysis of the photocatalytic mechanism shows that the redox reaction of the MoSTe/g-GeC heterostructure occurs on the layer with strong redox ability, and their light absorption ability is significantly enhanced compared to single-layers, which effectively improves the photocatalytic properties. It's a potential high-efficiency photocatalytic materials for direct Z-scheme heterostructure. In this paper, the stability, electronic properties, optical absorption properties, and photocatalytic mechanism of the MoSTe/g-GeC heterostructure is systematically studied. The results show that the heterostructure is a direct z-scheme heterostructure, and the photocatalytic performance is better than that of MoSTe and GeC monolayers. [Display omitted] • MoSTe/g-GeC heterostructure is a direct Z-scheme heterostructure, which is suitable for photocatalytic water splitting. • MoSTe/g-GeC heterostructure has excellent absorption coefficient (9.8 × 104 cm−1) in the visible and ultraviolet ranges. • The bandgap of MoSTe/g-GeC heterostructure can change from indirect bandgap to direct bandgap under partial strain. [ABSTRACT FROM AUTHOR]

Introducing defects into Pd-based metallene has been shown to significantly enhance its electrocatalytic performance. In this study, we embedded a new type of atomic-scale cavities into the basal plane of PdMo bimetallene (c-PdMo) through precise etching. These cavities introduced tensile strain and increased the generalized coordination number (CN ̅), resulting in superior performance in formate oxidation reaction (FOR) and methanol oxidation reaction (MOR), with mass activities of 5.01 mA μ g NM − 1 and 5.38 mA μ g NM − 1 , respectively. Notably, a two-electrode system comprising commercial Pt/C and c-PdMo coated on carbon paper achieved cell voltages of only 0.517 V and 0.362 V at 10 mA cm−2 for FOR and MOR, respectively. Additionally, density functional theory calculations revealed that the deliberate lattice tensile strain and enhanced coordination numbers reduced the D-band center of defective PdMo, which improved OH adsorption and reduced CO adsorption, thus optimizing FOR and MOR catalysis on the surface of c-PdMo bimetallene. [Display omitted] • PdMo bimetallene with atomic-scale cavities (c-PdMo) was prepared via etching. • Atomic-scale cavities can regulate coordination number and strain of bimetallene. • Atomic-scale cavities can modulate the surface adsorption energies of CO and OH. • c-PdMo exhibited highly-efficient mass activity for FOR and MOR. [ABSTRACT FROM AUTHOR]

Sustainable and energy-efficient ammonia production requires facile nitrogen reduction for hydrogen preservation and inorganic fertilizers. A nitrogen reduction apparatus with optimal stability, selectivity, and activity for ambient temperatures and pressure is needed to catalyze ammonia synthesis. This paper describes the investigation of using transition metal carbonitrides as catalyst to reduce molecular nitrogen electrochemically to NH 3 at room temperature and atmospheric pressure. Density functional theory calculations determine the competition among associative, dissociative, and Mars-van Krevelen mechanisms where in most cases the Mars-van Krevelen is a more favorable reaction pathway. VCN and NbCN are the best candidates for ammonia production via the Mars-van Krevelen mechanism at low onset potentials of −0.52 V and −0.53 V vs reversible hydrogen electrode on the (100) facets. These carbonitrides are predicted to favor nitrogen reduction reaction rather than hydrogen evolution reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper elucidates the mechanism of BN as sintering additive and the enhancement for LLZO performance. The introduction of the sintering additive boron nitride (BN) to Li 6.25 Ga 0.25 La 3 Zr 2 O 12 (LGLZO) can effectively eliminate the insulating phase Li 2 CO 3 and form the liquid phase Li 3 BO 3 along the grain boundaries, which significantly enhances the relative density (from 72.4% to 92.9%), ionic conductivity (from 1.3 × 10 − 5 to 6.7 × 10 − 4 S cm − 1 ), mechanical strength (from 1.36 to 5.36 GPa) and air stability (anti-Li 2 CO 3) of the electrolyte. Density functional theory (DFT) results reveal that the formation of Li 3 BO 3 contributes to the improvement of the interfacial lithiophilicity, and the interface resistance is reduced from 1219 to 32 Ω cm−2. The critical current density (CCD) is enhanced from 0.1 to 0.7 mA cm−2, and the cells can be stably cycled for more than 1000 h at a current density of 0.2 mA cm−2 with a low overpotential at room temperature. [ABSTRACT FROM AUTHOR]

The catalysts for oxygen reduction reaction (ORR) are of great significance to the development of electrochemical energy systems. In this paper, the ORR catalytic performance of Mn–Ni dual-metal doped N-coordinated graphene is studied by density functional theory (DFT). The results show that the catalysts with dual-metal active sites are more stable than that with single metal site, and all catalysts show certain catalytic activity. The reaction pathway analyses of catalysts with two different adsorption configurations of O 2 show that when O 2 is adsorbed on two metal sites, OOH will automatically split into OH and O. When O 2 is adsorbed on Mn site alone, the other site does not participate in the adsorption of oxygen-containing intermediates. The thermodynamic calculation results show that the catalytic performance is mainly influenced by the adsorption strength of O, which is controlled by the number of active sites involved in the adsorption, bond length and the number of transferred electrons at the active sites. The G-MnNiN 6 -3 shows the best catalytic performance with an overpotential of 0.453 V and a reaction energy barrier of 0.19 eV. The results of this study highlight the potential application of Mn–Ni dual-metal doped N-coordinated graphene as a highly efficient non-precious catalyst. • The ORR catalytic performance of Mn–Ni dual-metal doped N-coordinated graphene is studied for the first time. • The adsorption of O 2 can be classified into single adsorption and co-adsorption on bimetallic catalyst. • The catalytic performance is most affected by the adsorption strength of O. • The best catalyst shows the overpotential of 0.453 V and a reaction energy barrier of 0.19 eV. [ABSTRACT FROM AUTHOR]

Hydrogen production from water splitting is a popular subject at present. Therefore, we design the hBNC/Janus MoSSe heterojunctions for hydrogen evolution of photocatalytic water splitting. This investigation is based on the density functional theory. The results indicate that the band alignments of the hBNC/Janus MoSSe heterojunctions are typical type-II. According to the direction of built-in electric field in the heterojunction, we confirm that the hBNC/Janus MoSSe is the direct Z-scheme heterojunction. In addition, the electron mobility and optical absorption coefficient are improved in the hBNC/Janus MoSSe heterojunctions. The hBNC/SeMoS has higher reduction reaction overpotential (χ H2 = 3.34 eV) than it (χ H2 = 3.06 eV) in the hBNC/SMoSe, while the oxidation reaction overpotential (χ O2 = 0.07 eV) in the hBNC/SMoSe is higher than it (χ O2 = -0.06 eV) in hBNC/SeMoS. Furthermore, the change of Gibbs free energy under the external potential which is provided by the photoexcited carriers with the light irradiation confirms that the hydrogen evolution reaction is exothermic and could react spontaneously. This work indicates that the hBNC/Janus MoSSe heterojunctions have the potential in hydrogen production of photocatalytic water splitting. [Display omitted] • This paper confirms that the hBNC/Janus MoSSe is the direct Z-scheme heterojunction. • The electron mobility is enhanced in the hBNC/Janus MoSSe heterojunctions. • The optical absorption coefficient is also improved. • The hBNC/Janus MoSSe can spontaneously complete HER. [ABSTRACT FROM AUTHOR]

Despite great potential in several applications, the pseudo-ternary system Al 2 O 3 –CaO–Cr 2 O x is an overlooked phase diagram due to the formation of a few toxic, carcinogenic, and water-soluble Cr6+ compounds. In the research paper, equilibrium experimentation of selected compositions was conducted at 1073, 1373, and 1673 K and investigated using XRD, SEM-EDS, and leaching tests. Further, thermodynamic modeling of limited databases of the pseudo-ternary system Al 2 O 3 –CaO–Cr 2 O x was validated using DFT calculations. Including the recently discovered novel phase CaAl 2 Cr 2 O 7 (wuboraite), the seven phases not available in the SGTE SUBstance (SSUB) database, along with the CaCrO 4 and CaCr 2 O 4 phases existing therein, were modeled using Density Functional Theory (DFT). Based on the above experiments and the present CALPHAD model, we have calculated the isothermal sections (1073, 1373, and 1673 K) of the Al 2 O 3 –CaO–Cr 2 O x system for different oxygen partial pressures (P (O 2)= 0.21 atm and P (O 2)= 10−8 atm). [ABSTRACT FROM AUTHOR]

Electrolysis of water and splitting of urea to produce hydrogen are identified as one of the most attractive approach to reduce environmental pollution. However, this approach is both promising and challenging. In the paper, the NiFeZr LDH material was in situ grown on Ni foam through a one-step hydrothermal process. The electrochemistry activity of the NiFeZr LDH electrode was investigated by two probe reactions, one for the oxidation of urea and the other for the oxidation of water. It is worth mentioning that whether it is the oxidation reaction of urea (potential of 1.42 V @ 10 mA cm−2) or water (overpotential of 350 mV @ 10 mA cm−2), the doping of Zr improves the catalytic activity of the material. What is worth mentioning that the oxidation of urea does significantly decrease energy consumption compared to the oxidation of water. However, experiments show that the catalytic active sites are different in the two reactions. We speculate that iron is the active site for the oxidation of water, while zirconium is the active site for the oxidation of urea. Experiments demonstrate that the promoted performance is assigned to the exposure of the centre site, the rapid charge transfer rate and the improved electron configuration. Density functional theory analysis indicates that this NiFeZr LDH electrode presents optimal adsorption energy for urea, which improves the catalytic activity of the material. The NiFeZr LDH material present superior electrocatalytic performance for water oxidation reaction (Overpotential of 350 mV@10 mAcm−2) and urea oxidation reaction (potential of 1.42 V@10 mAcm−2). [Display omitted] • NiFeZr LDH nanoarrays were prepared by typical hydrothermal processes. • The NiFeZr LDH presents an improved activity with small overpotentials of 350 mV for water oxidation. • The NiFeZr LDH presents an improved activity with potentials of 1.42 V for urea oxidation. [ABSTRACT FROM AUTHOR]

As a fascinating approach for sustainable NH 3 production, the electrocatalytic nitrogen reduction reaction (NRR) is still hampered by low Faraday efficiency due to high energy required for inert N N triple bond activation and competitive hydrogen evolution reaction (HER). In this paper, we propose a method to increase the NRR catalytic activity by constructing bimetallic sites on boron nitride (BN) monolayer. In order to approach the efficient NRR region, the metal-based linear-scaling relationship between adsorbed intermediates is broken by synergistic effects between the bimetallic active sites. TiRu-BN was identified as an effective NRR electrocatalyst with low limiting potential (−0.28 V) and superior selectivity after systematic evaluation of the thermal stability, electrochemical stability, activity, and selectivity of 36 homo- and heteronuclear diatomic catalyst candidates. Analysis on the origin of high performance shows the screened high-performance diatomic catalyst is located in the region of moderate linear-scaling relationship breaking of intermediates. Breaking the linear scale relationship to the most significant extend does not imply the most improved catalytic activity. This work not only provides experimentally synthesizable exceptional NRR electrocatalyst candidates, but also provides theoretical guidance for practical application of efficient NRR electrocatalyst. [Display omitted] • Metal dimers anchored on defective BN monolayers for NRR investigated. • TiRu-BN was identified as high performance NRR electrocatalyst. • Synergistic effect of dual metal site breaks scaling relationship of intermediates. • High-performance catalyst shows the moderate scaling relationship breaking. [ABSTRACT FROM AUTHOR]

[Display omitted] • Simple bispyrene-based probe (BisPyH) with aggregation-induced enhanced emission for PA and DNP ultrasensitive detection, respectively was constructed. • BisPyH exhibited relatively bright green intermolecular excimer emission with AIEE effect in DMSO/H 2 O (1:1, v/v) via intermolecular π-π interactions among pyrene units. • Qualitative and quantitative detection of PA or DNP in real water. • Naked-eye detection of PA or DNP in solid state by TLC plates and test strips. It was still important to explore excimer emission-based fluorescence probes for nitroaromatics detection by formation or destruction of pyrene excimer with strong emission change. In this work, we have synthesized a simple bis(pyrene) derivative (BisPyH) and studied its optical behavior by using UV–vis and fluorescent spectroscopy. In pure DMSO solution, it emitted a weak blue fluorescence due to the formation of excimer states, on the contrary, the BisPyH in the DMSO/H 2 O (v/v, 1:1) mixture solution was self-assembled to form aggregates via intermolecular π-π interactions among pyrene units, giving almost 10-fold fluorescence enhancement compared to that in pure DMSO solution. The formed aggregates just offered a perfect platform for the selective detection PA and DNP explosives by quenching the bright green intermolecular-excimer emission in competitive environment. BisPyH exhibited a limit of detection (LOD) towards PA, and DNP as low as 7.32 × 10−8, and 8.11 × 10−8 M, respectively. Subsequently, the fluorescence quenching mechanism was demonstrated by the density functional theory (DFT), UV–vis and fluorescence spectra, SEM, and the quenching constants. Furthermore, filter paper strips and thin-layer chromatography (TLC) plates coated with BisPyH were able to detect PA and DNP in the practical application. [ABSTRACT FROM AUTHOR]

Vacancy engineering has repeatedly proven to be a powerful strategy for manipulating material properties. The important influence of selenium vacancies (V Se) on the physicochemical properties of rhenium diselenide (ReSe 2), exciting applications can be opened in areas such as catalysis and photoelectric devices. However, the effects of V Se on electronic structure, carrier lifetime, and electrochemical activity of ReSe 2 have remained inadequately explored and poorly elucidated. Herein, hydrothermal controlled growth of ReSe 2 with vacancy (V Se -ReSe 2) is used by different synthesis strategies, revealing its growth mechanism. An ethanol-assisted hydrothermal method based on carbon paper was used to adjust the V Se concentration by changing the time parameters. Mediated excitonic effects in the transient absorption (TA) spectroscopy and photoluminescence response of ReSe 2 regulated by V Se were characterized. The defect level (DL) leads V Se -ReSe 2 to produce a unique defect emission peak, and the V Se -mediated exciton dynamics problem was discussed. Moreover, the TA result of V Se -ReSe 2 shows that high V Se concentration prolongs carrier lifetime and causes high carrier separation efficiency and electron utilization. The electrocatalytic hydrogen evolution reaction of ReSe 2 catalyst revealed the ability of V Se concentration to regulate the electrochemical activity, which provides ideas for vacancy management catalyst performance. The presence of DL and the reduction of band gap are indicated by density functional theory, which confirms the regulatory effect of V Se concentration on the electronic structure of ReSe 2. This work proffers an optimal solution strategy for hydrothermal preparation of ReSe 2 , which demonstrates the feasibility of regulating electrochemical activity by vacancy engineering, and the excellent performance of V Se -ReSe 2 makes it show great potential in many fields such as water cracking and physical devices. [Display omitted] • A regulation strategy for the successful construction of V Se rich ReSe 2 nanoflowers was developed. • DFT investigated the reduction of the band gap and orbital contribution of ReSe 2 regulated by V Se. • Mediated excitonic effects in the TA and PL response of ReSe 2 regulated by V Se were analyzed. • The effectively regulate the HER activity of V Se -ReSe 2 were analyzed. Vacancy engineering is powerful for manipulating material properties. Selenium vacancies (V Se) exert significantly impact on the physicochemical properties of rhenium diselenide (ReSe 2), triggering applications in catalysis and photoelectric devices. However, the effects on electronic structure, carrier lifetime, and electrochemical activity are inadequately explored and poorly elucidated. Herein, hydrothermal-controlled growth of ReSe 2 with V Se is synthesized by different strategies. The ethanol-assisted hydrothermal method can adjust V Se concentration of ReSe 2 on carbon paper by time parameters. Mediated excitonic effects were characterized in the transient absorption spectroscopy and photoluminescence of V Se -regulated ReSe 2. The defect level produces unique defect emission peak, and the V Se -mediated exciton dynamics problem was discussed. The transient absorption result shows that high V Se concentration can optimize carrier lifetime, carrier separation efficiency, and electron utilization. The electrocatalytic hydrogen evolution reaction of ReSe 2 catalyst revealed the electrochemical activity regulation by V Se concentration, which provides ideas for enhancing catalyst performance. Density functional theory result confirms the role of selenium vacancies in the regulation of the electronic structure of ReSe 2. This work proffers an optimal solution strategy for hydrothermal preparation of ReSe 2 , and demonstrates the feasibility of regulating electrochemical activity by vacancy engineering. The excellent performance is beneficial for water cracking and physical devices. [ABSTRACT FROM AUTHOR]

ZnO/CuInS 2 composites were synthesized by using electrospun ZnO chain structures as a template, along with InCl 3 , CuCl 2 , and thiourea as sources of indium, copper, and sulphur, respectively. The ZnO/CuInS 2 core-shell structure enhances light absorption and carrier transport efficiency. Moreover, ZnO/CuInS 2 exhibits superior light absorption and photocatalytic hydrogen production performance compared to ZnO, with a peak hydrogen production of 4188.24 μmol g−1. The arrangement of energy levels within the ZnO/CuInS 2 heterojunction is the crucial factor in enhancing photocatalytic properties. Increased electrons distribution near the interface facilitates the transport performance of charge carriers, which accelerates hydrogen production kinetics at the interface, and promotes greater participation of photogenerated electrons and holes in catalytic reactions. Combined with the application of density functional theory, the computational analyses of work function and differential charge support this assertion. This paper introduces a fresh method for creating innovative photocatalysts and grasping the reaction mechanism involved in photocatalytic hydrogen generation. The ZnO/CuInS 2 heterojunction, encompassing CuInS 2 nanosheets surrounding ZnO nanofibers, displayed exceptional hydrogen production capacity. The most remarkable hydrogen production achievement was 4188.25 μmol g−1 in 6 h, a value more than 623.7 times superior to that of pure ZnO. The disparity in charge density highlighted the presence of significant charge transfer at the interface of ZnO/CuInS 2. This reinforces the fact that the ZnO/CuInS 2 construction and interface charge transfer are crucial in elevating its photohydrogen production capabilities. [Display omitted] • ZnO/CuInS 2 was synthesized by the electrospinning method. • The hydrogen production of heterojunction reached 4188.25 μmol g−1 in 6 h. • The mechanism was analyzed by DFT calculation. [ABSTRACT FROM AUTHOR]

As a promising candidate for accident-tolerant fuel (ATF) cladding materials, FeCrAl alloys are susceptible to hydrogen embrittlement (HE) under high-temperature radioactive water environments. Understanding the HE mechanism of FeCrAl is crucial, and studying H 2 dissociative adsorption can provide valuable insights since it is the first step in the HE processes. In this paper, we investigated the H 2 dissociative adsorption on Fe (110) and FeCrAl (110) surfaces using first-principles calculations based on Density Functional Theory (DFT). Our results indicate that the decomposition of H 2 molecules on FeCrAl (110) surfaces is significantly affected by surface elemental effects compared to Fe (110) surfaces. Specifically, Al atoms weaken both the H 2 decomposition and the H binding strength of Al-containing sites. Cr atoms decrease the decomposition tendency of H 2 in certain configurations, but Cr aggregation enhances the binding strength of H atoms on Cr-containing sites. The mechanism underlying the Al/Cr weakening effects on H 2 decomposition is due to the charge deficiency through alloying. Our findings have generalized implications for studying the interactions between iron-based alloys and hydrogen in various applications such as hydrogen storage, transportation, and prevention. • The strength of H 2 –Fe/Cr/Al interactions follow the order: H 2 –Al < H 2 –Cr < H 2 –Fe. • Al atoms have strong weakening effect on H 2 dissociation compared to Fe. • Cr atoms have slight weakening effect on H 2 dissociation compared to Fe. • The Cr aggregation can enhance H 2 –Cr interaction & H binding strength. • The weakening effects of Al & Cr on H 2 dissociation are caused by the charge deficit of Al & Cr after alloying with Fe. [ABSTRACT FROM AUTHOR]

Two-dimensional material rhenium disulfide (ReS 2) has attracted much attention recently as a potential electrochemical catalyst for the Hydrogen Evolution Reaction (HER). The ReS 2 monolayer is found to be catalytically inert. The challenge lies in activating the ReS 2 monolayer to increase HER output. One of the approaches to this lies in depositing small metal clusters on the monolayer. This paper examines the formation and stability of small metal clusters on 1T distorted ReS 2 monolayer using dispersion-corrected Density Functional Theory. Four different kinds of transition metal clusters, viz. Au, Pt, Mo, and Cr are investigated for geometry and binding on the ReS 2 monolayer. HER activity of each type of ReS 2 -supported metal cluster is investigated based on computed free energy. The HER mechanism was investigated for clusters with optimal activity, and it was found that while the ReS 2 monolayer follows the Volmer-Heyrovsky route, for the transition metal cluster decorated ReS 2 , the Volmer-Tafel route is more probable. • ReS 2 basal plane is catalytically inert; therefore, surface activation is required. • ReS 2 monolayer decorated with small clusters of Au, Pt, Mo and Cr are stable. • ReS 2 supported Au, Pt and Mo clusters are HER active, especially Au3, Pt4 and Mo5, but Cr clusters are not. • The clusters on ReS 2 follow a Tafel mechanism, with lower activation barriers than pure ReS 2. [ABSTRACT FROM AUTHOR]

Hydrogen production by urea electrolysis is a green, energy conservation and environment protection method. Compared with traditional water electrolysis for hydrogen production, it not only saves costs and energy consumption, but also can treat urea wastewater to purify the environment. In this paper, the sea urchin-like nanoneedles (M (M = Cr, Mo and W)–FeCo 2 P/NF) arrays with different doping elements M (M = Cr, Mo and W) were prepared by hydrothermal method and moderate temperature phosphating method. It is proved that the doping of different elements in the same group cooperates to adjust the electronic structure of Co 2 P, thereby increasing the electrochemical active area and improving the active site. What is noteworthy is that Mo–FeCo 2 P/NF material only needs potential of 1.305 V and overpotential of 232 mV to drive 50 mA cm−2 for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER). The Mo–FeCo 2 P/NF (±) electrolyser can drive a current density of 10 mA cm−2 at a potential of 1.471 V, and is stable for at least 12 h in urea electrolysis. The density functional theory (DFT) demonstrates that Mo–FeCo 2 P/NF electrode has a moderate Gibbs free energy (G H∗) of H adsorption. This work put forward a new strategy for improving the activity and stability of transition metal phosphides by doping strategy for urea electrolysis. The Mo–FeCo 2 P/NF (±) electrolyser cell for only 1.471 V to provide current density of 10 mA cm−2, which is one of the best electrochemistry performances reported up to now. [Display omitted] • Mo, Fe co-doped Co 2 P electrodes was synthesized for the first time through hydrothermal processes. • This Mo–FeCo 2 P nanoarrays exhibits enhanced activity of the urea splitting (cell voltage of 1.471 V @10 mA cm−2). • DFT show that the Mo–FeCo 2 P material exhibits the minimum Gibbs free energy. [ABSTRACT FROM AUTHOR]

The dehydrogenation enthalpy, a crucial thermodynamic parameter, determines the difficulty of hydrogen desorption in V–Ti–Cr–Fe alloy, but it is unaffordable to predict and modify the dehydrogenation enthalpy and investigate the synergistic effects of structural and chemical parameters relying on conventional experimental methods. In this paper, an extreme gradient boosting (Xgboost) model with feature selection is developed, which can obtain a relative error under 15% in prediction on most of the data. Moreover, the genetic algorithm is utilized for optimizing alloy composition having suitable dehydrogenation enthalpy. The accuracy of prediction and optimization is demonstrated by the subsequent experimental validation, where the error between calculation and experiment is within 4.5%. Density function theory (DFT) is used to analyze the key features provided by machine learning, with results suggesting that the volumes, valence electrons, and bulk module factors have a significant impact. This research supplies an efficient way of using machine learning to predict and optimize the dehydrogenation enthalpy. In addition, DFT calculation also validates the feature importance outputted by machine learning and reveals the principle of feature effects at the microscopic aspect. • ML models predict precisely the dehydrogenation enthalpy of V–Ti–Cr–Fe alloy. • Properties calculation optimized by GA have good agreement with experiments. • Explanation of volume, electron and module factors affecting enthalpy using DFT. [ABSTRACT FROM AUTHOR]

In this paper we investigate the nature of hydrogen diffusion in substoichiometric TiC using simulations. Specifically, we examine how well connected the carbon structural vacancies are in TiC x using percolation theory and how many structural carbon vacancies are connected to the surface of TiC x. This provides direct insight into the number of sites available for hydrogen storage and the interconnected nature of the carbon vacancy network. We also compute the binding energies and migration energies of hydrogen in TiC x using density functional theory. This is conducted over a range of carbon concentrations from nearly stoichiometric TiC to Ti 2 C and includes the differences in vacancy ordering. We find that the migration energy of hydrogen in TiC x generally decreases with carbon loss and is associated with the tetrahedral interstices near them but that the binding energy of hydrogen to TiC x is independent of carbon concentration. Furthermore, we show that this migration path can occur through the tetrahedral interstices, which is influenced by local carbon concentration. These results also demonstrate the vacancy ordered R 3 ¯ m Ti 2 C structure does not possess any more superior ability to store or transport hydrogen than the F d 3 ¯ m Ti 2 C structure. • Hydrogen insertion in TiC x should occur for carbon concentrations below TiC 0.7. • The energy barriers for hydrogen diffusion drop with carbon concentration. • Hydrogen diffusion occurs from carbon vacancy to tetrahedral interstice. • It is easier to diffuse hydrogen into ordered F d 3 ¯ m Ti 2 C than R 3 ¯ m Ti 2 C. [ABSTRACT FROM AUTHOR]

The perovskite-type hydride compounds are potential candidate materials in the field of hydrogen storage. This paper presents a systematical study of XTiH 3 (X = K, Rb, Cs) using density functional theory. The analysis of formation energy, elastic properties and phonon dispersion curves indicate that all the studied materials are thermodynamically, mechanically and dynamically stable. By analyzing the B/G ratio, it is determined that these compounds are brittle materials. The electronic properties reveal that the XTiH 3 compounds exhibit semi-metallic characteristics. The charge transfer characteristics of these compounds were analyzed using Bader partial charges. Moreover, the thermodynamic characteristics of these compounds were investigated and the dependence of their free energy, entropy and heat capacity on the temperature were analyzed. Finally, the gravimetric hydrogen storage capacities of KTiH 3 , RbTiH 3 and CsTiH 3 were calculated to be 3.36, 2.22 and 1.65 wt%, respectively. The hydrogen desorption temperatures of KTiH 3 , RbTiH 3 and CsTiH 3 were found to be 209 K, 161 K and 107 K, respectively. To our knowledge, this study represents the very first investigation of XTiH 3 compounds and offers valuable references to this hydrogen storage material. [Display omitted] • XTiH 3 (X = K, Rb, Cs) perovskite have been investigated using first-principles. • XTiH 3 perovskite exhibit thermodynamic, mechanical and dynamical stability. • The gravimetric hydrogen storage capacity is found to be 3.36 wt% for KTiH 3. [ABSTRACT FROM AUTHOR]

Lead-free halide double perovskites (DPs) with superior photoelectric performance are of great importance in perovskites materials family. In this paper, a series of rare-earth (RE) based Cs 2 NaRECl 6 (RE = Y, Ce–Nd, Sm–Gd, Dy–Lu) DPs microcrystals (MCs) were prepared by convenient hydrothermal method. Cs 2 NaCeCl 6 and Cs 2 NaEuCl 6 MCs exhibit typical UV emission from the 5d→4f transition of Ce3+ and orange-red emission from characteristic 5D 1 → 7F 0 , 5D 0 → 7F 1 , 5D 0 → 7F 2 , 5D 0 → 7F 3 , 5D 0 → 7F 4 transitions of Eu3+, respectively. The blue light emissions of Cs 2 NaYCl 6 (300–650 nm) and Cs 2 NaLuCl 6 (300–550 nm) are from the respective self-trapped exciton states (STEs). In addition, the bandgap and partial density of state (PDOS) of Cs 2 NaRECl 6 (RE = Ce, Eu, Y, Lu) were calculated based on density functional theory (DFT) to have a further insight into the optical properties of the RE-DPs. The as-prepared RE based DPs have potential applications in advanced lighting, displaying and anti-counterfeiting, etc. [ABSTRACT FROM AUTHOR]

Lead-free halide double perovskites (DPs) with superior photoelectric performance are of great importance in perovskites materials family. In this paper, a series of rare-earth (RE) based Cs 2 NaRECl 6 (RE = Y, Ce–Nd, Sm–Gd, Dy–Lu) DPs microcrystals (MCs) were prepared by convenient hydrothermal method. Cs 2 NaCeCl 6 and Cs 2 NaEuCl 6 MCs exhibit typical UV emission from the 5d→4f transition of Ce3+ and orange-red emission from characteristic 5D 1 → 7F 0 , 5D 0 → 7F 1 , 5D 0 → 7F 2 , 5D 0 → 7F 3 , 5D 0 → 7F 4 transitions of Eu3+, respectively. The blue light emissions of Cs 2 NaYCl 6 (300–650 nm) and Cs 2 NaLuCl 6 (300–550 nm) are from the respective self-trapped exciton states (STEs). In addition, the bandgap and partial density of state (PDOS) of Cs 2 NaRECl 6 (RE = Ce, Eu, Y, Lu) were calculated based on density functional theory (DFT) to have a further insight into the optical properties of the RE-DPs. The as-prepared RE based DPs have potential applications in advanced lighting, displaying and anti-counterfeiting, etc. [ABSTRACT FROM AUTHOR]

Seawater is one of the richest hydrogen sources around our environment, so it has a lot of advantages to decompose and produce hydrogen. However, considering that chloride ions in seawater have a strong corrosive action on the electrode. Therefore, the design and exploration of highly effective and antiseptic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) electrocatalysts were studied. It's worth noting that Cu 2 S@Ni 3 S 2 /NF is engaged as a difunctional electrode in this study, which drives a current density of 10 mA cm−2 with requiring overpotentials of only 78 mV and 170 mV, and highlights its significant selectivity of OER and HER. The results show that the increased activity of Cu 2 S@Ni 3 S 2 /NF electrode can be assigned to the synergistic catalysis of (211) and (110) crystal faces, as well as the transfer and the increase of the number of active sites caused by lattice defects. The results of density functional theory show that Cu 2 S material has optimal free energy of the adsorbed states for H, indicating that the introduction of Cu 2 S promotes the kinetics of the reaction. The introduction of Ni 3 S 2 material greatly improves the conductivity of Cu 2 S@Ni 3 S 2 /NF electrode. This paper proposes novel insights into the exploration of environmentally friendly and corrosion resistant difunctional catalysts for seawater splitting. Cu 2 S@Ni 3 S 2 /NF is used as a difunctional catalyst in this study, which provides a current density of 10 mA cm−2 with required overpotentials of only 130 mV and 170 mV, and highlights its significant selectivity of OER and HER. [Display omitted] • Cu 2 S@Ni 3 S 2 electrodes was synthesized for the first time through hydrothermal processes. • The overpotential of Cu 2 S@Ni 3 S 2 electrode is only 130 m V at 100 mA cm−2 for OER. • Density functional theory analysis demonstrates that the Ni 3 S 2 material presents optimal free energy for H. [ABSTRACT FROM AUTHOR]

· The fragmentation of cationic resin was studied using the statistical fragmentation model. · The degradation of cationic resin by ·OH was calculated by DFT. · Active sites of cationic resin monomer were predicted. · Dihydroxy addition and elimination reactions played a major role. · The decomposition mechanisms were proposed by combing physical models and chemical calculations. The treatment and disposal of radioactive waste are presently facing great challenges. Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks. In this paper, a simplified model of cationic exchange resin is proposed, and the degradation processes of cationic resin monomer initiated by hydroxyl radicals (·OH) are clarified by combining statistical molecular fragmentation (SMF) model and density functional theory (DFT) calculations. The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation. The meta -position of the sulfonic group on the benzene ring is the most active site, and the benzene ring without the sulfonic group has a certain reactivity. The C11-C14 and C17-C20 bonds, on the carbon skeleton, are the most easily broken. It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation, carbon skeleton cleavage and benzene ring separation. The decomposition mechanisms found through the combination of physical models and chemical calculations, provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons. [Display omitted] [ABSTRACT FROM AUTHOR]

This study introduces an inventive acetone-sensing device seamlessly integrated into a disposable face mask, enabling real-time continuous breath monitoring. The sensor demonstrates exceptional sensitivity, registering a response of 8.22 at 1 ppm and an impressive sensor response of 57.33 at 100 ppm of acetone concentration. Particularly noteworthy is the remarkable lower limit of detection (LOD) of 0.076 ppm within the concentration range of 0.1–0.8 ppm, underscored by a robust R2 value of 0.994. To validate practicality, the Pd/WO 3 sensor was fabricated onto cellulose paper and utilized for real-time breath analysis, yielding a substantial sensor response of 1.70 at 8 vol% (equivalent to a single exhale breath volume). The unique design incorporates a built-in disposable face mask, facilitating dependable and convenient real-time breath analysis. Additionally, this research explores the profound impact of introducing acetone and Pd atoms on the energy levels and dipole moments. The species elucidated through density functional theory (DFT) investigations encompassing WO 3 , WO 3 -acetone, Pd-WO 3 , and Pd-WO 3 -acetone species. This work presents an innovative and cost-effective approach for developing a portable, non-invasive, and highly sensitive acetone-sensing device, effectively integrated into a disposable face mask for real-time breath analysis. This pioneering technology holds immense potential for various applications in healthcare and beyond. [Display omitted] • This Pd/WO 3 based device can measures continuous exhaling breath. • Hierarchical structure confirmed by scanning and tunneling electron microscopy. • Binding energy peaks corresponding to W6+ and Pd0 oxidation states were observed. • Cellulose paper based device was integrated with disposable face mask. [ABSTRACT FROM AUTHOR]

[Display omitted] • A colorimetric and fluorescent probe NI-CIN was designed for hydrazine detection. • NI-CIN displayed an effective detection of hydrazine in real water and soil samples. • Visual detection of hydrazine under aqueous and vapor phases are realized. • NI-CIN is successfully used to image hydrazine in living cells and zebrafish. Detection of hydrazine is particularly important given its toxicity and extensive application in various industries. In the present paper, a colorimetric fluorescent probe NI-CIN based on 1,8-naphthalimide derivative was rationally designed and simply synthesized for specific detection of hydrazine based on the intramolecular charge transfer (ICT) mechanism. Upon the addition of hydrazine, a significant fluorescence enhancement at 556 nm could be observed within 4 min with a distinct color change from colorless to bright yellow, readily observed by naked eye. Except for HRMS and 1H NMR, density functional theory (DFT) calculations were also performed to support the sensing mechanism. In addition, eco-friendly paper test strips were easily prepared by NI-CIN for selective and real-time detection of hydrazine under aqueous and vapor phases. Furthermore, NI-CIN shows many potential applications for detecting hydrazine in real water and soil samples along with bio-imaging in HepG-2 cells and zebrafish. [ABSTRACT FROM AUTHOR]

• Optimal path for ethyl acetate as a byproduct of vinyl acetate synthesis by ethylene method. • Adsorption properties of PdAu(100) surface species during ethyl acetate generation. • The combination of density functional theory and kinetic Monte Carlo method. Vinyl acetate (VAc) is an important chemical raw material for the production of polyvinyl alcohol and polyvinyl acetate, among others. The preparation of vinyl acetate over PdAu catalysts using ethylene, oxygen and acetic acid as raw materials is one of the mainstream processes for the production of vinyl acetate in the world. The by-product ethyl acetate in this process is more difficult to be completely removed, and it is an impurity component in vinyl acetate products that needs to be strictly controlled in content. However, studies on the mechanism of ethyl acetate generation have not been reported, which limits the improvement of the purity of vinyl acetate products and the optimization of the ethyl acetate separation process. In this paper, the mechanism of ethyl acetate generation during ethylene vinyl acetate reaction on PdAu catalysts was systematically investigated using a combination of density functional theory (DFT) and kinetic Monte Carlo (kMC) simulations. The results show that the species tend to adsorb to the Pd-Au bridge sites, diagonal Pd-Pd vacancies, and diagonal Pd-Au vacancies of PdAu(100), and the Pd on the catalyst surface interacts more strongly with the adsorbed species. The dominant pathway for the generation of ethyl acetate on PdAu(100) is CH 2 CH 2 * + O *→ CH 2 CH* + H * → CH 3 CH* + CH 3 COO* → CH 3 COOCHCH 3 * + H * → CH 3 COOCH 2 CH 3 *, where the hydrogenation of CH 2 CH* to CH 3 CH* is the rate-control step in the dominant pathway for the generation of ethyl acetate. This step has an energy barrier of 1.09 eV and a reaction heat of 0.90 eV. The study of the generation mechanism of the by-product ethyl acetate in this paper is hoped to provide more targeted guidance and suggestions for the modification of Pd-Au catalysts, so as to reduce the generation of ethyl acetate as a by-product, to reduce the energy consumption required for the separation, and to enhance the purity of vinyl acetate products. [Display omitted] [ABSTRACT FROM AUTHOR]

To alleviate the environmental pressure caused by SF 6 emissions, SF 6 /N 2 has been widely used in power systems as a replacement gas. In case of abnormal equipment failure, SF 6 /N 2 will decompose and produce many kinds of toxic and harmful gases, so it is necessary to place molecular sieves to safeguard the insulation performance of the equipment. Since γ-Al 2 O 3 is the main component of molecular sieves, the adsorption of N 2 O and NF 3 on the surface of γ-Al 2 O 3 (110) is systematically calculated in this paper using density functional theory to investigate the adsorption energy, charge transfer, density of states (DOS), electrons density difference (EDD), electron localization function (ELF) and frontier molecular orbital theory for their stable configurations. The calculated results show that although N 2 O adsorption on γ-Al 2 O 3 (110) is slightly stronger than NF 3 , both gases have weak interactions with γ-Al 2 O 3 (110) and thus may both be physisorbed. This paper deepens the basic understanding of adsorbent adsorption of SF 6 /N 2 decomposition gases in power equipment, and provides a theoretical basis for the optimisation study of adsorbents required for equipment with SF 6 /N 2 as the insulating medium. [Display omitted] [ABSTRACT FROM AUTHOR]

• Sc @BB is a promising electrocatalyst towards NRR. • The NRR performance of Sc @BB could be further improved by strains. • The NRR performance of TM@BB is related to the intrinsic properties of TMs. NH 3 plays an important role in industrial production, while it is still a challenge to develop a promising catalyst for NH 3 synthesis. In particular, the metal borides have attracted much attention because of their excellent catalyst performances towards N 2. In this paper, we have theoretically studied the N 2 reduction reaction (NRR) by employing the transition metal (TM = Co, Cr, Cu, Fe, Mn, Mo, Ni, Sc , Ti, V, Zn, Nb, Pd, Rh, Ru or Zr) doped bilayer borophene (BB). After the screening, it is found that Sc -doped BB (Sc @BB) exhibits excellent NRR performance with the limiting potential of -0.43 V, and the hydrogen evolution reaction (HER) could be well suppressed. The limiting potential could be further improved into -0.40 V by applying 0.30 % uniaxial strains to the system. In addition, the machine learning method was employed to understand the catalytic mechanism, the results revealed that the NRR performance of TM@BB is strongly related to the inherent properties of TM atoms, such as the d -electron number, electronegativity, first ionization energy, atomic radius, and atomic number. Therefore, our paper not only proposed a promising electrocatalyst for NRR, but also further extend the application of transition metal-boron based two dimensional materials in NRR. [Display omitted] [ABSTRACT FROM AUTHOR]

In the advent of the digital revolution, Artificial Intelligence (AI) has emerged as a pivotal tool in various domains, including materials design and discovery. This paper provides a comprehensive review of the AI methodologies integrated within this context, encompassing materials informatics, density functional theory, molecular dynamics, and finite elements analysis. We further delve into the transformative role of AI within process engineering, manufacturing, and industry 4.0, with a focus on manufacturing process optimization techniques. Highlighting the importance of active learning, self-correcting processing, and digital twins in the era of smart manufacturing, this review underscores the impact of big data and data quality. The paper provides an insight into the challenges and future prospects, pointing towards the tremendous potential AI holds for revolutionizing the field of materials science. • Comprehensive exploration of AI methods in Materials Design and Discovery. • Review of the transformative role of AI within process engineering. • Discussion on the importance of data quality and quantity in the era of Big Data. • Insight into challenges and potential of AI in the field of Materials Science. [ABSTRACT FROM AUTHOR]

• The mechanism of inhibiting the generation of methane and improving the selectivity of olefin on the Co(020) surface was found. • The paper investigates the reaction mechanism and elementary reaction kinetics of the cobalt carbide-catalysed FTO process by quantum mechanical methods. • The DFT study of Fischer–Tropsch synthesis of low carbon olefins on Co 2 C is limited to C 1 and C 2 species. In this paper, the generation mechanism of ethylene, propylene and butene will be further studied. Fischer–Tropsch Synthesis to lower olefins (FTO) is an important non-petroleum route to produce lower olefins. Nanoprisms Co 2 C has been discovered as a promising FTO catalyst possessing high selectivity to olefins and low CH 4 selectivity for its exposing (020) facet. Density Functional Theory (DFT) was used to understand the reason for inhibiting methane formation, the chain growth mechanism and dominant formation pathway of three main low olefins. The results show that the activation energy for CH 2 * to couple with CH* (0.51 eV) was much lower than that for further hydrogenation to form CH 3 * (0.66 eV), which was the key species to produce methane. Therefore, the mechanism inhibiting methane formation was Co 2 C(020) promoting CH 2 *-CH*coupling rather CH 2 * hydrogen. Moreover, it can be predict that the carbon chain would not grow too long, because the coupling activation energy for the C 1 -C 1 coupling, C 1 -C 2 coupling, C 1 -C 3 coupling were 0.51 eV, 0.54 eV and 0.69 eV, respectively. At last, it can be predicted that propylene was the easiest to produce, followed by ethylene and butylene, because their barrier energy were 1.58 eV, 1.64 eV and 2.12 eV, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

• One new 2D Y(III) metal-organic framework based on Tris(3'-F-4'-carboxybiphenyl)amine was synthesized and characterized. • Y-MOF exhibited thermal stability and water-stable stability. • Y-MOF could instantly and sensitively detect Cr 2 O 7 2−, CrO 4 2−, and nitrofuran antibiotics in aqueous solution. • The quenching mechanism could be mainly attributed to competitive absorption, and electron transfer mechanism. By using tris(3'-F-4'-carboxybiphenyl)amine (H 3 TFBA) and rare earth element Y(III), one 2D layered structure with the formula {[Y(TFBA)(H 2 O) 2 ]·4H 2 O·DMF} n (1) , has been solvothermal synthesized and fully characterized. Structural analyses demonstrated that the central Y(III) ions were interconnected by deprotonated TFBA3− to produce a 2D layer, and the neighboring layers were developed into a 3D supramolecular structure through hydrogen-bonding interactions. Powder X-ray diffraction (PXRD) of 1 exhibited excellent different pH and solvent stability. Luminescent experiment indicated that 1 could instantly and sensitively detect Cr 2 O 7 2−, CrO 4 2−, NFZ and NFT in aqueous solution with low detection limits of 2.27 × 10−5 M, 2.03 × 10−5 M, 3.4 × 10−6 M, 1.09 × 10−5 M, respectively. Moreover, convenient and naked-eye detection were also provided by exquisitely made 1 fluorescence test papers and mixed matrix membranes (MMMs). Importantly, the possible quenching reasons have been thoroughly examined, which were supported by PXRD analysis, UV-vis spectra, luminescence experiments and density functional theory (DFT) calculation. [Display omitted] [ABSTRACT FROM AUTHOR]

The Dirac cone in the single-layer graphene limits its application in electronic devices such as Schottky barrier diodes and field-effect transistors. Thus, we make the novel heterostructures based on graphene to solve this problem. The electronic and optical properties of pristine and Ag/Au/Cu-doped graphene/MoS 2 heterostructures are investigated by using the density functional theory. For the Ag/Au/Cu-doped MoS 2 monolayer, the results show that they are magnetic. Their bands across the Fermi level, which indicates these systems are metallic. For the Ag/Au/Cu-doped graphene/MoS 2 heterostructures, they are metallic and nonmagnetic. Especially in the Au-doped graphene/MoS 2 , the Dirac cone opens about 66 meV. It means that Au-doped graphene/MoS 2 has the potential to be a candidate material for high speed electronic devices. Compared with pristine heterostructure, the probability of electron transition in the low energy region is the enhanced in Ag/Au/Cu-doped systems. The optical absorption coefficient of doped heterostructure is enhanced in the range of 0–0.4 eV and 1.7–2.7 eV. This work indicates that these heterostructures have a certain potential in the application of nanodevices. [Display omitted] • This paper confirms that the graphene can adsorb on Ag/Au/Cu-doped MoS 2 monolayer stably. • This paper finds that the Dirac cone in the Au-doped graphene/MoS 2 heterostructure opens about 66 meV. • The introduction of Ag/Au/Cu atoms in graphene/MoS 2 heterostructure can make the electron transfer at low energy. • The optical absorption coefficient is improved in these doped heterostructures. [ABSTRACT FROM AUTHOR]

With the development of industrialization, the use of mercury in industry has become more and more widespread, causing serious impacts on the environment. It is therefore urgent to find new effective ways to combat mercury pollution. In this paper, The effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS 2 has been investigated based on the first nature principle of density functional theory. The electronic structures and optical properties of the adsorbed systems were calculated after atomic doping. The results show that the absolute value of the adsorption energy of the intrinsic adsorption system is small and does not favour the adsorption of Hg on WS 2. However, after C, P, Ni and Au doping, the adsorption energy of the system is significantly increased and a strong charge transfer between WS 2 and Hg atoms occurs, as well as a significant change in the band gap of the structure. This suggests that atomic doping favors the adsorption of Hg by WS 2. The effect of O doping on the adsorption system is not significant. In addition, a study of the optical properties revealed that the static dielectric constants of the system appeared to increase to varying degrees after the doping of the atoms. The doping of P, Ni and Au atoms increases the light absorption coefficient and contributes to the photocatalytic efficiency of the structures. The doped atoms cause a red shift in the reflectivity peak of the adsorbed system. In summary, the doping of C, P, Ni and Au enhances the adsorption of Hg atoms on WS 2. O doping has less effect on the adsorption of Hg on WS 2. • In this paper, the effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS2 was investigated. • The results show that atomic doping favors the adsorption of Hg by WS2. • Atomic doping alters the electronic properties of the structure. • Atomic doping alters the optical properties of the structure. [ABSTRACT FROM AUTHOR]

This paper uses comprehensive approach to propose quantitative evaluations of the electrode materials' electronic rate-capability calculated by density functional theory (GGA/GGA + U). Here, a novel approach is introduced to evaluate electrical rate-capability by calculating electronic conductivity (σ) for the case studies. Application of the evaluated materials as electrodes of Li-ion battery is taken into account. Also, thermal conductivity and Seebeck coefficient for the materials are calculated. Here, three novel alternatives for LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM111), in which introduced by substitution of transition metals, are LiNi 1/3 Mn 1/3 Fe 1/3 O 2 (NMF), LiMn 1/3 Fe 1/3 Co 1/3 O 2 (MFC), and LiFe 1/3 Co 1/3 Ni 1/3 O 2 (FCN). The evaluated materials are compared with each other and other relevant electrodes, based on structural, electrochemical, and electrical properties. The voltage reaction of the cathode materials is calculated by two approaches, namely internal and Fermi energy methods. According to the obtained results, MFC and NMF have superior properties on NCM. It is concluded that the NMF can be the best alternative for NCM conditionally. [ABSTRACT FROM AUTHOR]

Rubidium cations (Rb+) significantly improve the overall performance of organic-inorganic hybrid perovskite based devices and have gained exceptional attention due to their good thermal and structural stability. In this paper, we have evaluated the physical attributes of rubidium based Rb 2 TlRhF 6 via DFT code using TB-mBJ potential. Structural stability has been confirmed through negative formation energy and calculated tolerance factor. Band structure and TDOS profile confirm semiconductor nature with 3.2 eV direct bandgap at (L-L) symmetry points. A ductile nature with metallic bonding is observed through the investigation of elastic attributes. Optical analysis of Rb 2 TlRhF 6 indicates great absorption in the UV region. Low thermal conductivity and electrical resistivity, along with a high value for power factor, resulted in high ZT value of 0.8 and 800 K. The combined qualities provide a stunning and exciting picture of this compound for use in thermoelectric advanced technologies. [ABSTRACT FROM AUTHOR]

• In this paper, we report a 1,8-naphthalimide/ triphenylamine-based fluorescent probe (TPA-NI-NO 2) for the specific detection of 4‑methoxy-thiophenol (MTP) with good selectivity among the thiophenols. • The probe can "turn on" detect MTP with the limit of detection (LOD) of 80 nM and no obvious response to relevant analytes and homologues. • The sensing mechanism was explored by HPLC experiment and the PET process was determined by density functional theory (DFT) calculations. • The Gibbs free energy (DG) analysis for the reaction between the probe and different thiophenols were obtained by the theoretical calculations to study the specificity of the probe. • The probe was successfully applied to monitor the MTP in Hela cells. Thiophenols as a series of industrial products are widely used and high toxicity to the organisms and the environment. The fluorescent probe technique offers important insights into thiophenols convenient sensing. Herein, we report a 1,8-naphthalimide/ triphenylamine-based fluorescent probe (TPA-NI-NO 2) for the specific detection of 4‑methoxy-thiophenol (MTP). The probe can "turn on" specific detect MTP with the limit of detection (LOD) of 80 nM among various relevant analytes and homologues (p -Cl-C 6 H 4 SH, p -NO 2 - C 6 H 4 SH, C 6 H 5 SH and o -CH 3 - C 6 H 5 SH). The sensing mechanism was explored by the HPLC experiment and the PET process was determined by density functional theory (DFT) calculations. In addition, the specificity of the probe was also studied by the Gibbs free energy (ΔG) analysis of the reaction between the probe and different thiophenols. The reaction between probe and MTP gives the minimum of the ΔG value (∼ -9.7280 kcal/mol) and that of other thiophenols-mediated is -2.5283 to -5.8911 kcal/mol, which proves the thermodynamic chemical equilibrium can optimize the design of reaction-based fluorescent probes with excellent specificity. At last, TPA-NI-NO 2 was successfully applied to Hela cells imaging. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel 2H-MOene and its Janus structure are predicted to be a promising piezoelectric material. • The novel 2D-MOene shown a superior piezoelectric coefficient d11 (d11 = 6.09 pm/V for Ti2OH2). • MOene and its Janus structure satisfy the rule of d 11 (_F) < d 11 (_Cl) < d 11 (_Br) < d 11 (_I). Two-dimensional (2D) piezoelectric materials have been widely studied because of their broad application prospects. In this paper, the piezoelectric properties of a MXene-like 2D material (MOene) and its Janus structure are reported by first-principles calculations. The dynamic stability of these 2D materials are verified based on phonon spectra. The semiconductor properties of materials are based on the calculation of energy bands. The origin of piezoelectric polarization of MOene and its Janus structure is explained based on differential charge density and Bader charge analysis. The piezoelectric stress tensor of the material is calculated based on density functional perturbation theory (DFPT). The theoretical prediction results show that the piezoelectric properties of MOene and its Janus structure are better than those of 2D 2H-MoS 2 , and the in-plane piezoelectric coefficient d 11 of Ti 2 OH 2 reaches 6.09 pm/V. Our research shows that MOene and its Janus structure add an important member to the 2D piezoelectric material library, and provide a new sample for the study of piezoelectric properties based on the 2D material library. [ABSTRACT FROM AUTHOR]

Cyanide is a typical toxic reducing agent prevailing in wastewater with a well-defined chemical mechanism, whereas its exploitation as an electron donor by microorganisms is currently understudied. Given that conventional denitrification requires additional electron donors, the cyanide and nitrogen can be eliminated simultaneously if the reducing HCN/CN− and its complexes are used as inorganic electron donors. Hence, this paper proposes anaerobic cyanides oxidation for nitrite reduction, whereby the biological toxicity and activity of cyanides are modulated by bimetallics. Performance tests illustrated that low toxicity equivalents of iron-copper composite cyanides provided higher denitrification loads with the release of cyanide ions and electrons from the complex structure by the bimetal. Both isotopic labeling and Density Functional Theory (DFT) demonstrated that CN−-N supplied electrons for nitrite reduction. The superposition of chemical processes reduces the biotoxicity and enhances the biological activity of cyanides in the CN−/Fe3+/Cu2+/ NO 2 – coexistence system, including complex detoxification of CN− by Fe3+, CN− release by Cu2+ from [Fe(CN) 6 ]3−, and NO release by nitrite substitution of −CN groups. Cyanide is the smallest structural unit of C/N-containing compounds and serves as a probe to extend the electron-donating principle of anaerobic cyanides oxidation to more electron-donor microbial utilization. [Display omitted] • A novel anaerobic cyanides oxidation and its metabolic pathway were found. • Complex detoxification of coexisting systems facilitates cyanide metabolisms. • Bimetallic modulation promotes the cyanide detoxification and electron release. • The probing role of cyanides reveals the bioavailability of N-containing compounds. [ABSTRACT FROM AUTHOR]