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In recent years, it has been demonstrated that the energetic properties of many tetrazole-containing compounds can be enhanced through the formation of the corresponding N-oxides. The introduction of N–O groups increases the oxygen balance of tetrazole compounds, while providing additional coordination sites and enriching the coordination modes between tetrazole compounds and metal ions. The introduction of O atoms alters the polarity of the substance from N to N–O, the packing and density increase and therefore the detonation velocity (VD) and pressure (P) also increase. Based on this, energetic coordination polymers (ECPs) with tetrazole N-oxides serving as ligands possess extremely high research value. In this paper, we aim to summarize the existing ECPs based on tetrazole N-oxides briefly and discuss their advantages, emphasizing their excellent stability and application prospects. [ABSTRACT FROM AUTHOR]

Xanthine derivatives were identified as inhibitors of the N6-methyladenosine (m6A) demethylase activity of fat-mass-and-obesity-associated protein (FTO) by activity-based high-throughput screening using the m6A-sensitive ribonuclease MazF. Pentoxifylline exhibited L -ascorbic acid concentration-dependent inhibitory activity against FTO, an unprecedented mode of inhibition, indicating that L -ascorbic acid is a promising key for designing FTO-specific inhibitors. [ABSTRACT FROM AUTHOR]

Herein, a 2,5-dihydroxyterephthalic acid-based cocrystal complex was facilely synthesized using a mixture of ethanolic solutions of the two coformers under a few minutes at room temperature. The high photocurrent ratio of 712 between the illumination and dark states and the successful fabrication of a phosphorconverted light-emitting diode device make this cocrystal complex a promising candidate in fields of photoelectric detectors and solid-state lighting. [ABSTRACT FROM AUTHOR]

Supramolecular organic frameworks (SOFs) are widely used for biological detection and drug delivery. In this study, a SOF system was fabricated through the self-assembly of photosensitive triarylboron (TAB), TAB-6-methyl, and CB[8]. The maximum fluorescence emission of TAB-6-methyl was greatly enhanced and red-shifted from 560 nm to 610 nm after SOF formation. The SOF can specifically respond to a microRNA by dissembling and then combining with microRNA, which is accompanied by a fluorescence shift from 610 nm to 560 nm, thus providing a ratiometric readout for microRNA detection. The photosensitivity of TAB-6-methyl can be further improved by forming a SOF, which can be used in photodynamic therapy. By constructing another guest molecule, TAB-5-1-cRGD, we successfully embedded cRGD in the SOF system to improve its tumor-targeting ability. Moreover, we used this SOF system as a fluorescence imaging probe for targeted tumor imaging and as a drug carrier system for loading DOX to achieve combined photodynamic and chemotherapy treatment of tumors. [ABSTRACT FROM AUTHOR]

The exploration of electrides, especially stabilized at ambient pressure, is of great interest in condensed matter physics due to their intriguing properties induced by interstitial anionic electrons (IAEs). Herein, on the basis of first-principles calculations, we have proposed a novel metastable Li11Sb2 electride, dubbed as C2/m-II phase, which is quenched from pressurized Li11Sb2 with a C2/m-I symmetry through an in-plane Li4 ring rotation mediated by IAEs. The stability of the C2/m-II phase can be attributed to the redistribution of IAEs and reduction of internal energy generated by depressurization. Interestingly, the C2/m-II phase is predicted to possess unexpected superconductivity and an anisotropic work function. The IAE-induced Fermi surface nesting and the resultant acoustic phonon softening play a critical role in the superconductivity. Our study might provide an alternative way to prepare metastable electrides with interesting properties. [ABSTRACT FROM AUTHOR]

A novel metal–organic framework (MOF) host–guest material [Cd3(EtOIPA)4(HAD)2]·H2O has been successfully synthesized by the reaction of 5-ethoxyisophthalic acid (EtOIPA), acridine (AD) and Cd(II) salts under hydrothermal conditions. Structurally, the title MOF possesses a trinucleate Cd(II) based 2D double-layer with the protonated AD cations as the template encapsulated into the grids. The combination of experiments and theoretical calculations reveals that the orderly arrangement of EtOIPA dimers, protonated AD cations and trinucleate Cd(II) clusters generates highly delocalized π-electron channels with a prolonged exciton lifetime. The MOF powders show bright yellow emission with a long lifetime of 50.63 ns. Photoelectrochemical measurements reveal a high photocurrent density ratio of 290 between light and dark conditions at 0 V bias potential, making it a perfect self-driven photodetector. By coating the yellow phosphor on a commercially available blue LED, a high performance white LED with CIE, CCT and CRI values of (0.325, 0.336), 88.2 and 5844 K, respectively can be obtained. [ABSTRACT FROM AUTHOR]

The development of organic–inorganic hybrid materials with long-lived room temperature phosphorescence (RTP) has attracted tremendous attention owing to their promising applications in the optoelectronic and anti-counterfeiting fields. In this work, by the selection of lead halide and electron-poor heteroaromatic molecule 1,10-phenanthroline (phen), a coordination polymer [Pb(phen)Cl2] has been synthesized under hydrothermal conditions. This complex shows an alternating arrangement of a long-range order of phen π-conjugated systems and lead halide inorganic chains as revealed by X-ray single-crystal structural analysis. This structural character and special chemical components endow this hybrid material with a rare example of red room temperature phosphorescence. Its electronic structure and electronic transition behavior were further examined by theoretical calculations. Meanwhile, the film of the complex features remarkable angle-dependent polarized emission and photoelectric performance. [ABSTRACT FROM AUTHOR]

Tantalum (Ta) is an interesting transition metal that exhibits superconductivity in its elemental states. Additionally, several Ta chalcogenides (S and Se) have also demonstrated superconducting properties. In this work, we propose the existence of five high-pressure metallic Ta–O compounds (e.g., TaO3, TaO2, TaO, Ta2O, and Ta3O), composed of polyhedra centered on Ta/O atoms. These compounds exhibit distinct characteristics compared to the well-known semiconducting Ta2O5. One particularly interesting finding is that TaO3 shows an estimated superconducting transition temperature (Tc) of 3.87 K at 200 GPa. This superconductivity is primarily driven by the coupling between the low-frequency phonons derived from Ta and the O 2p and Ta 5d electrons. Remarkably, its dynamically stabilized pressure can be as low as 50 GPa, resulting in an enhanced electron–phonon coupling and a higher Tc of up to 9.02 K. When compared to the superconductivity of isomorphic TaX3 (X = O, S, and Se) compounds, the highest Tc in TaO3 is associated with the highest NEF and phonon vibrational frequency. These characteristics arise from the strong electronegativity and small atomic mass of the O atom. Consequently, our findings offer valuable insights into the intrinsic physical mechanisms of high-pressure behaviors in Ta–O compounds. [ABSTRACT FROM AUTHOR]

A new strategy to achieve long-lived room temperature phosphorescence performance has been developed via the formation of a donor–acceptor structure in a coordination polymer, which features a lifetime (40.22 ms) three orders of magnitude higher than that of pristine phosphor. It also shows remarkable angle-dependent polarized emission. [ABSTRACT FROM AUTHOR]

Recently, the development of novel metal-containing resists has received much attention in extreme ultraviolet lithography (EUVL) owing to their smaller sizes and higher EUV absorptivity than traditional polymer resists. Herein, we report zinc (Zn)–VBA, a novel stable zinc–oxo cluster-based photoresist molecule with the [Zn4O]6+ inner core and six organic ligands based on 4-vinylbenzoic acid. Zn–VBA was simply prepared by the reactions between the zinc-oxide and 4-vinylbenzoic acid, exhibiting atomically precise structure and good batch stability. Based on single-crystal X-ray diffraction analysis, the size of Zn–VBA is 2.2 nm, which is in line with the high-resolution requirements for advanced lithography technology. Zn–VBA exhibits excellent thermal stability up to 400 °C, much better than the reported zinc-based clusters. Moreover, theoretical studies have revealed the roles of organic ligands in their high thermal stability. Spin-coating methods were employed to fabricate homogenous thin films of Zn–VBA, which showed a quite small roughness value in the absence of viscosifiers, as confirmed by atomic force microscopy images. More importantly, the Zn–VBA films performed well in the electron beam lithography (EBL) and EUVL tests without the addition of photoinitiators, giving prominent pattern lines. This work proves the structural advantages of benzoic-acid-based zinc–oxo clusters as promising EUV patterning materials, which inspire future exploration of metal–oxo clusters (MOCs) resist materials for advanced lithography. [ABSTRACT FROM AUTHOR]

Three-fold interpenetrating Zn(II) MOF with the dense π-stacking of flexible ligands exhibit long-lived phosphorescence emission up to 91 ms at room temperature. Photoelectric measurements show efficient electro-hole separation based on the long lifetime of triplet state exciton. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have earned considerable attention as a promising photovoltaic technology for future power generation. Spiro derivatives are often used as a hole-transporting layer (HTL) in highly efficient PSC devices. However, spiro derivatives have low hole mobility and conductivity in their native form and require complicated preparation. Therefore, using other low-cost chemical compounds that are easy to synthesize becomes essential to improve conductivity and, thus, efficiency. The compound MS-T, also known as 4,4′-(thiophene-2,5-diyl)bis(N,N-bis(4-methoxyphenyl) aniline), was intentionally theoretically designed to have a symmetrical structure. It consists of the core of a heterocyclic compound (thiadiazole), with two triphenylamine molecules attached at positions 2 and 5 to improve the electron density of the compound. The modeled PSC was numerically optimized with many significant parameters, including layer thickness, temperature, doping density, defect density, and other characteristics. This optimization was carried out using the SCAPS-1D program. Furthermore, flaws in the interfaces between the electron-transporting layer (ETL)/perovskite and HTL/perovskite were considered, and their impact on performance was also examined. The optimized PSC has an attainable efficiency of up to 30.66%. [ABSTRACT FROM AUTHOR]

Basal and prismatic slips induced by thermoelastic stresses during the growth of 4H-SiC are investigated by using the finite element method (FEM) and considering factors such as the crystal diameter, temperature, and off-axis angle. It is found that with the increase of the crystal diameter from 6 to 8 inches, the prismatic slip more likely occurs, leading to a higher density of basal plane dislocations (BPDs). However, the basal slip hardly changes. The temperature difference, rather than the growth temperature, is the primary factor contributing to the increase in the slip stresses. The stresses of the basal slip are significantly affected by a small off-axis angle, whereas those of the prismatic slip are not unaffected until the off-axis angle reaches 30 degrees. The mechanism for the decrease of the density of BPDs along the growth direction in an 8 inch 4H-SiC crystal is elucidated. We verify that the prismatic slip in an 8 inch 4H-SiC crystal contributes more to the BPD formation than the basal slip. [ABSTRACT FROM AUTHOR]

In this study, a crystalline material CuPMTT was synthesized via coordination self-assembly strategy. The surfaces of CuPMTT are densely populated with thiol groups that effectively capture Hg2+ ions, achieving an adsorption rate nearing 90% and a separation coefficient of 4.51 against Cu2+, thus outperforming conventional adsorbents and presenting a significant advancement in environmental protection chemistry. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), self-assembled by metal ions and organic ligands, have been utilized as active layers in resistive random-access memory (RRAM) devices due to their tunable composition and structure advantages, high porosity, and diverse interactions between guest molecules and host frameworks. As one kind of special MOF, MOF nanosheets not only inherit the benefits of MOFs but also present unique two-dimensional nanoscale thicknesses. Their special properties make them beneficial for fabricating MOF films. Thus, they could be promising materials for RRAM devices. Herein, we synthesized two porphyrin MOF nanosheets and then fabricated MOF films by spin-coating. After that, we used the films for resistive switching (RS) layers in memory devices. The as-fabricated RRAM devices exhibit write-once-read-many-times memory characteristics and good nonvolatile stability. Furthermore, due to the unique luminescence of the porphyrin linker, we investigated the light-induced resistive switching characteristics. The result shows that these porphyrin-based MOF nanosheet films exhibited ternary memory properties. This RS modulation is likely related to the photoinduced electrons and holes forming along channels consisting of porphyrin molecules. This MOF-based light-mediated memory device can be a candidate for achieving environment-responsive devices and has applications in information storage devices. [ABSTRACT FROM AUTHOR]

The contemporary world faces issues related to energy, the environment, and food security. The use of carbon capture, storage, and utilization technologies can help reduce CO2 emissions from fossil fuels, which will result in major advancements toward dual carbon targets. In addition to promoting environmentally friendly manufacturing, chemical industries may replace fossil fuel-based raw materials with renewable biomass for the synthesis of organic acids and syngas. Although several studies are being conducted on co-valorization of CO2 and biomass feedstocks to produce organic acids and fine chemicals using biotechnology, thermocatalysis, electrocatalysis, and photocatalysis, there are still various obstacles in scaling up clean production, including (i) addressing environmental concerns, (ii) the intricate structure and chemical composition of biomass, (iii) conversion mechanisms and processes, (iv) designing catalyst materials with higher durability and recyclability, (v) greener solvent systems for catalysis and extraction, (vi) the deployment of modern technologies for characterization, (vii) training and guidelines for industrial operations, and (viii) governmental financing and policy. The sustainable manufacturing of biobased products from raw feedstocks produced from biomass has been made possible via technological breakthroughs in photo-/biorefineries, which are essential for the clean and environmentally friendly synthesis of organic acids. It is anticipated that clean production of organic acids from biomass will have a dominant market share, benefiting from both socioeconomic and environmental factors. With future technical developments, the valorization of feedstocks obtained from biomass together with CO2 for manufacturing fuels and fine chemicals will be more ecologically and economically feasible. [ABSTRACT FROM AUTHOR]

The concept of sustainable development is driving shell biorefineries to develop a cost-effective and environmentally benign approach to transform chitin into high-value products. This study describes a green, simple, and flexible shell biorefinery process for producing two kinds of nanochitins (NCh), chitin solid residues (ChSRs) and chitin nanocrystals (ChNCs), by using p-toluenesulfonic acid-assisted hydrothermal treatment. The ChSR is a bundled nanocrystal with a long length ranging from 100 nm to 450 nm and a width ranging from 10 nm to 30 nm. It has an excellent interfacial behavior between the water and oil phases due to its amphiphilic nature; thus, a foodstuff-related emulsion has been successfully fabricated from soybean oil and a ChSR suspension without the addition of any synthetic surfactants. The further hydrolysed ChNC with a length and width range of 25–225 nm and 15–30 nm, respectively, and a high zeta potential of 41 mV exists as an individual nanocrystal. Owing to the abundance of positively charged groups distributed on its surface, ChNC enables self-assembly to a highly ordered hierarchical structure. Hence, ChNCs show promising results in fabricating large-area photonic films, e.g. for application in bright and vivid automobile painting. Altogether, we provide a novel approach to produce NCh materials from crustacean shell waste and bridge the gap from process engineering to high-value product development. [ABSTRACT FROM AUTHOR]

Plastic material performance is strongly correlated to the polymer's molecular weight. Obtaining a sufficiently high molecular weight is therefore a key goal of polymerization processes. The most important polyester polyethylene terephthalate (PET) and the new polyethylene furanoate (PEF) require metal catalysts and time-consuming production processes to reach sufficiently high molecular weights. Metal catalysts, which are typically antimony or tin for polyesters, end up in the plastic products which may result in sustainability and ecological challenges. When the less reactive comonomer isosorbide is introduced to produce (partly) biobased materials with enhanced thermal properties, such as polyethylene-co-isosorbide furanoate (PEIF), reaching high enough molecular weight becomes even more challenging. This study presents an easily implementable approach to produce high molecular weight PET and PEF polyesters and their isosorbide copolyesters PEIT and PEIF by coupling lower molecular weight polymer chains by the reactive diguaiacyl oxalate (DGO) chain extender. DGO is so reactive, that the use of metal catalysts can be completely avoided and it helps avoiding an extra solid-state polymerization step. In addition, DGO distinguishes itself from typical chain extenders by its ability to be completely removed from the resulting polymer, thereby avoiding the inherent drawbacks associated with typical chain extenders. [ABSTRACT FROM AUTHOR]

The field of low-dimensional polarized photodetectors has become a leading focus for optical communications, remote sensing, imaging research and other studies. Achieving high polarization anisotropy while maintaining other critical detection performance metrics continues to be a significant hurdle. In this work, self-powered hybrid junction polarized photodetectors, which are based on a Pt/Sb2Se3 Schottky junction combined with a Sb2Se3/ZnO heterojunction, are proposed. The Pt/Sb2Se3/ZnO hybrid junction photodetector has a high responsivity of 120 mA W−1, a high specific detectivity of 1012 Jones (1000 Hz), and an ultrafast rise/decay time (833 μs/830 μs) upon 880 nm light irradiation at zero bias. Specifically, the polarization anisotropy of the designed device is measured to be 1.69. Based on the finite element method calculation, the favorable overall photoelectric properties of the photodetectors are attributed to the consistency and synergy of the built-in electric field introduced by the near fully depleted hybrid junctions, which promote the effective separation of carriers and reduce recombination losses. Because the photodetector can be used as a polarized light receiver, it can be further applied in near-infrared encrypted communication. This work provides a promising route for the design of high-performance polarized photodetectors towards realistic applications. [ABSTRACT FROM AUTHOR]

High-quality and large-size crystals are ideal scintillation screens to achieve high-resolution X-ray imaging. However, it is difficult to obtain large-size scintillation crystals due to the limitations of crystal growth technology. Here, organic–inorganic hybrid Mn-based single crystals (TBP2MnBr4, TBP = tetrabutylphosphonium) exhibit a high decomposition temperature (295 °C) and the TBP2MnBr4-melt has a low condensation point (48.75 °C), such a wide interval is of benefit to the melt processing method for preparing scintillation screens. The TBP2MnBr4-melt exhibits a low viscosity (η(Tm) = 238 mPa s) and flow activation energy (Ea = 10.754 kJ mol−1) making it easy to crystallize. It is worth noting that the low condensation point (Tc) of the TBP2MnBr4-melt is slightly higher than room temperature, and this narrow temperature interval can limit the rapid nucleation and growth of the crystals, allowing them to slowly crystallize into transparent ceramics (TC). Circular TBP2MnBr4-TC with a size of Φ 11.5 cm can be easily fabricated, which exhibits high optical transmittance, for realizing high-resolution (16 lp mm−1) X-ray imaging. This work brings a new strategy for preparing scintillation screens, as well as promoting the development of TC scintillators for X-ray imaging. [ABSTRACT FROM AUTHOR]

Ferroelectric tunnel junctions (FTJs) are garnering significant attention as leading candidates for next-generation synaptic devices in neuromorphic computing. In particular, HfOx-based FTJs offer several advantages over perovskite-based FTJs, including complementary metal–oxide semiconductor compatibility, scalability, low power consumption, and rapid operation. Furthermore, the ferroelectric properties of HfOx are enhanced through silicon doping, as silicon's smaller atomic radius than hafnium makes it ideal for ferroelectric devices. In this study, we investigate HfSiOx-based FTJs, demonstrating robustness to thermal variation by maintaining consistent use of Si doping and materials while optimizing annealing temperatures. We also examine the high tunneling efficiency, address the inherent depolarization field challenges, and delve into their potential applications in neuromorphic computing. Specifically, this approach emulates key aspects of human brain learning, including Pavlov's dog experiments, potentiation, depression, paired-pulse facilitation, and reservoir computing (RC). To demonstrate the device capability in the information processing of neuromorphic systems, image recognition simulations are performed using the MNIST database. These include online learning mechanisms related to the outcomes of potentiation and depression, as well as offline learning mechanisms related to the results of RC. [ABSTRACT FROM AUTHOR]

Yb-doped lead halide perovskite nanocrystals (NCs) have attracted significant attention due to their outstanding optical properties. However, scaling up the synthesis remains a practical challenge. Here, we present a scalable method for producing monodispersed Yb3+:CsPbCl3 NCs by simply heating up mixed reactants. The particle size and Yb3+ doping concentration of the produced CsPbCl3 NCs can be effectively controlled. The resulting NCs exhibit exciton and Yb3+ emissions, both can be fine-tuned by modifying the annealing temperature and duration. Unlike classical size evolution modes, we revealed that the monodispersity was attributed to a two-step nucleation and digestive ripening process. With the capability to yield over ten grams of high-quality Yb3+:CsPbCl3 NCs, our work may suggest a synthetic approach for a wide range of applications and demonstrates an alternative mechanism for forming monodispersed perovskite NCs. [ABSTRACT FROM AUTHOR]

As a promising approach to convert solar energy into a low-cost form, photoelectrochemical (PEC) water splitting is attracting a lot of attention from researchers. However, the PEC hydrogen production is limited by the oxygen evolution reaction. Therefore, it is necessary to find effective means to accelerate the water oxidation kinetics of photoanodes. In this work, a Co-MOF cocatalyst was modified onto Ti–Fe2O3 photoanodes using a simple hydrothermal method, which allowed greater adsorption and exposure of cobalt species with high catalytic activity. The composite photoanode Co-MOF/Ti–Fe2O3 demonstrates a higher photocurrent density of 3.9 mA cm−2 at 1.23 V vs. RHE, promoting water oxidation kinetics and the transfer of photogenerated carriers. This work provides an effective approach for constructing high-performance photoanodes using metal–organic framework materials. [ABSTRACT FROM AUTHOR]

Two mononuclear iron(III) complexes (XEA)[Fe(azp)2]·H2O (H2azp = 2,2′-azodiphenol, XEA = 2-fluoroethylammonium and 2-chloroethylammonium) are synthesized, which exhibit the counterion dependence of magnetic and fluorescent properties. The synergetic effect between abrupt spin crossover and fluorescence is observed in an iron(III) complex for the first time. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate reduction to ammonia (ENRA) in acidic media is currently a challenge. Herein, we presented a CoFe2O4/GO catalyst that exhibited a high faradaic efficiency (95.51%) and ammonia yield rate (1268.04 μmol h−1 cm−2) for ENRA under acidic conditions. The ENRA reaction mechanism was investigated through in situ ATR-FTIR spectroscopy and isotope labeling experiments. [ABSTRACT FROM AUTHOR]

Direct dithiolation of alkenes with thiols has been rarely reported. Herein, a simple cobalt-catalyzed aerobic approach has been developed to realize this transformation. With the aid of HFIP, diverse vicinal dithioethers including symmetric and unsymmetric ones could be obtained from readily available substrates. Gram-scale synthesis and late-stage modification of complex molecules highlight the practicability of this approach. [ABSTRACT FROM AUTHOR]

This study explores the spintronic properties of an innovative device incorporating in-plane bent zigzag phosphorene nanoribbons (ZPNRs). The device features ZPNRs with a channel length of 23.4 nm, bent into circular arcs with varying curvatures. We investigate the impact of mechanical deformation and gate voltage on the spin-dependent properties, including the density of states, transmission coefficients, and spin Seebeck coefficient (SSC). Our results demonstrate that the device exhibits a spin-semiconducting phase with tunable spin-splitting characteristics and spin-dependent transport properties, both of which are influenced by the curvature. An increase in the bending parameter markedly enhances spin splitting, leading to the SSC attaining values as high as 1.35 mV K−1. Moreover, the application of gate voltage further enhances both spin polarization and spin current. The significant impact of mechanical deformation and gate voltage on spintronic performance showcases the potential of bent ZPNRs for advanced applications. [ABSTRACT FROM AUTHOR]

The structural and sorption characteristics of a composite material consisting of a silica aerogel loaded with flufenamic acid were investigated using a variety of nuclear magnetic resonance techniques. The composite structure was analyzed using magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, which revealed significant interactions between the aerogel matrix and the FFA molecules. Solid-state 29Si NMR provided insights into the aerogel's stability, while 1H and 13C NMR confirmed the presence of FFA in the matrix, with signals from FFA molecules observed alongside tetraethoxysilane (TEOS) groups. Ethanol-induced desorption of FFA led to narrowed spectral lines, suggesting the breaking of intermolecular hydrogen bonds. 19F MAS NMR spectra indicated changes in FFA local environments upon loading into AG pores. Evaluation of CO2 sorption characteristics using 13C NMR demonstrated a slower sorption rate for AG + FFA than that for pure AG, attributed to decreased pore volume. Furthermore, nuclear Overhauser effect spectroscopy (NOESY) was employed to explore the conformational behavior of FFA within the aerogel matrix. The results indicated a shift in conformer populations, particularly those related to the rotation of one cyclic fragment relative to the other. These findings provide insights into the structural and sorption characteristics of the AG + FFA composite, which are valuable for developing novel drug solid forms. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogen evolution reaction (HER) offers a sustainable and clean route for hydrogen production. Developing a high-efficiency HER catalyst is extremely essential toward meeting future energy needs. Herein, the Sn-doped Ga2O3 monolayer, O-defected Ga2O3 monolayer, and Ru-adsorbed Ga2O3 monolayer with high electrocatalytic performances toward HER are reported (their H adsorption free energies are 0.169, 0.126 and 0.065 eV, respectively). The Sn-doped Ga2O3 monolayer follows the Volmer–Heyrovsky mechanism, and the O-defected Ga2O3 monolayer and Ru-adsorbed Ga2O3 monolayer are suitable for Volmer–Tafel mechanisms. The strain from −4% to 4% in the X- or Y-direction could linearly modulate the HER activities of the Sn-doped Ga2O3 monolayer and O-defected Ga2O3 monolayer. The Sn-doped Ga2O3 monolayer, O-defected Ga2O3 monolayer, and Ru-adsorbed Ga2O3 monolayer only manifest high HER catalytic activities in the strong acidic media. These phenomena can provide a rational approach to enhance the HER activity for Ga2O3 monolayer-based materials. [ABSTRACT FROM AUTHOR]

The electrochemical environment present at surfaces can have a large effect on intended applications. Such environments may occur, for instance, at battery or electrocatalyst surfaces. Solvent, co-adsorbates, and electrical field effects may strongly influence surface chemistry. Understanding these phenomena is an on-going area of research, especially in the realm of electrocatalysis. Herein, we modeled key steps in the ethanol oxidation reaction (EOR) over a common EOR catalyst, Rh(111), using density functional theory. We assessed how the presence of electrical fields may influence important C–C and C–H bond scission and C–O bond formation reactions with and without co-adsorbed water. We found that electric fields combined with the presence of water can significantly affect surface chemistry, including adsorption and reaction energies. Our results show that C–C scission (necessary for the complete oxidation of ethanol) is most likely through CHxCO adsorbates. With no electric field or solvent present C–C scission of CHCO has the lowest reaction energy and dominates the oxidation of ethanol. But when applying strong negative fields (with or without solvent), the C–C scission of CH2CO and CHCO becomes competitive. The current work provides insights into how electric fields and water solvent affect EOR, especially when simulated using density functional theory. [ABSTRACT FROM AUTHOR]

In this investigation, we employed the anharmonic phonon renormalization method to analyze the thermal conductivity of two-dimensional (2D) carbon materials, while also examining the influence of quartic (fourth-order) scattering on heat transport within this class of materials. Our study centered on a representative silicon–carbon (Si–C) 2D system, Si4C8. Notably, conventional Boltzmann transport equation (BTE) calculations with harmonic phonons are inadequate for estimating the thermal conductivity of these materials due to the emergence of imaginary frequencies. Consequently, to elucidate the primary contributors to its heat transport, we employed an integrated yet novel computational framework rooted in a first-principles methodology. This approach combines self-consistent phonon (SCP) theory and the BTE to scrutinize the thermal conduction behavior; the BTE is resolved in conjunction with SCP theory to comprehensively address the quartic anharmonic effects, encompassing both four-phonon (4ph) scatterings and the temperature-induced shift of phonon frequencies. Based on the calculation results, it is evident that the meticulous incorporation of anharmonicity renormalization is pivotal for precise evaluation of the thermal conductivity of 2D Si4C8 and establishing coherent temperature dependency. Through this comprehensive examination, we aim to establish a systematic methodology for investigating the thermal transport mechanisms of 2D Si–C phases with similar bonding networks, offering insights into the intricate relationships between their structural, mechanical, electronic, and thermal properties. [ABSTRACT FROM AUTHOR]

As an alternative to the traditional ammonia (NH3) synthesis method, the electrochemical reduction reaction of nitrate (NO3-RR) for NH3 production not only mitigates nitrate pollution but also yields economically valuable NH3. Cu2O nanomaterials exhibit excellent catalytic activity for NO3-RR with low cost and are beneficial for the rate-limiting step (NO3- to NO2-). In this work, Au-modified Cu2O nanocubes (Au/Cu2O NCs) were synthesized and used as an efficient NO3-RR electrocatalyst for NH3 production. At -0.75 V potential (relative to the reversible hydrogen electrode, RHE), Au/Cu2O NCs reach 39.79 mg h-1 mgcat-1 in NH3 yield and a faradaic efficiency of 92.93%. Furthermore, the localized surface plasmon resonance (LSPR) characteristics of Au and a narrow band gap of Cu2O can generate plasma and photoexcited electrons, which can efficiently utilize visible light to accelerate NO3-RR. Indeed, the synergistic effect between Au and Cu2O can result in an increased NH3 yield of 57.3 mg h-1 mgcat-1 under external light conditions for NO3-RR, 1.44 times higher than that without light. [ABSTRACT FROM AUTHOR]

The significant progress of perovskite solar cells (PSCs) in the past decade has shown enormous potential for industrialization; however, several critical issues such as long-term stability and potential lead leakage still need to be addressed. It is a practical challenge to overcome these issues through one approach. Herein, we introduce an ultraviolet absorbent and conductive passivation agent 4,40-diaminostilbene-2,20-disulfonic acid (DSDA) into SnO2 to down-convert ultraviolet light into visible light and enhance the conductivity of SnO2, thereby improving the light-stability and performance of PSCs. The amphoteric DSDA molecule with four functional groups can also passivate defects on the surface of SnO2 films, affect the crystal growth of the perovskite layer, and provide in situ protection against lead leakage. Our results show that the power conversion efficiency (PCE) of the PSCs increases evidently from 22.95% to 25.09% owing to the simultaneous enhancement of the photoelectric properties of SnO2 films and the critical SnO2/perovskite interfaces by adding DSDA into SnO2 films. Importantly, the DSDA-optimized PSCs without encapsulation exhibited enhanced operational and UV-light stability, as well as in situ fixation of leaked lead ions. This simultaneous enhancement of both optical and electrical properties of functional layers via adding a multifunctional organic compound provides an efficient strategy to effectively improve the efficiency and long-term stability of PSCs. [ABSTRACT FROM AUTHOR]

Carrier-selective passivating contacts in crystalline silicon (c-Si) solar cells have expanded from doped silicon films to non-silicon wide-bandgap materials to reduce parasitic absorption and production costs. Titanium oxide (TiOx) has emerged as one of the most promising materials and has achieved high performance in c-Si solar cells. In this work, TiOx is explored as a passivation interlayer in hole-selective contacts rather than conventional electron-selective contacts. Theoretical calculations and experimental results demonstrate that negative charges and shallow states in TiOx, derived from oxygen vacancies (VO), enhance surface passivation and assist hole tunneling, respectively. As a strategy to modulate VO, forming gas annealing is performed to further improve hole selectivity. By incorporating the TiOx passivation interlayer into MoOx-based c-Si solar cells, we achieve an improved efficiency and stability of the device, with the highest efficiency of 21.28%. This work advances the understanding of TiOx as a promising material to enhance hole selectivity for c-Si solar cells. [ABSTRACT FROM AUTHOR]

Designing hierarchical nanostructures and modulating the electronic structure are effective strategies for boosting the electrochemical performance of catalysts. Herein, a novel Co-Cu3P/NC@MXene catalyst with a unique 3D@2D structure is successfully fabricated through an in situ growth strategy. Metal--organic framework (MOF)- derived Co-Cu3P/NC octahedra are embedded in the interlayer gap of MXene, thereby creating a microenvironment that accelerated electron and mass transport. The incorporation of Co modulated the electronic structure of Cu3P, enhancing the electrochemical activity of the Co-Cu3P/NC@MXene catalyst. Furthermore, the hierarchical structure, constructed by combining 3D Cu3P/NC and 2D MXene, provided abundant electron transfer paths for the 3D@2D hybrid catalyst. As a result, Co-Cu3P/NC@MXene exhibited remarkable performance as a cathode in an alkaline electrolyte, reaching a lower overpotential of 110 mV vs. RHE, as well as a smaller Tafel slope of 62 mV dec-1. Furthermore, the power conversion efficiency (PCE) of the photovoltaics assembled with the Co-Cu3P/NC@MXene counter electrode was 8.18%, surpassing that of traditional Pt electrode-based devices (7.13%). This work offers a possible method for the controllable construction of MOF@MXene-based catalysts with hierarchical structures and tailored electronic structures for energy conversion applications. [ABSTRACT FROM AUTHOR]