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[Display omitted] • A double carbon encapsulated porous composite with compact interface was designed. • The P-Si@rGO@C electrode exhibited inspiring rate-capability and long-cycling life. • The storage mechanism was explored via reaction kinetics, Ex-situ tests, and DFT. • A Li x Si prelithiation suspension was provided to enhance the ICE of the full cell. Developing high-performance composites with fast charging and superior cycle life is paramount for lithium-ion batteries (LIBs). Herein, we synthesized a double-shell carbon-coated porous structure composite with a compact surface (P-Si@rGO@C) using low-cost commercial micron-sized silicon (Si) instead of nanoscale silicon. Results reveal that the unique P-Si@rGO@C features high adaptability to volume expansion, accelerates electron/ion transmission rate, and forms a stable solid electrolyte interphase (SEI) film. This phenomenon arises from the synergistic effect of abundant internal voids and an external double-layer carbon shell with a dense surface. Specifically, the P-Si@rGO@C anode exhibits a high initial coulombic efficiency (ICE) (88.0 %), impressive rate-capability (612.1 mAh/g at 2C), and exceptional long-term cyclability (972.2 mAh/g over 500 cycles at 0.5C). Further kinetic studies elucidate the diffusion-capacitance hybrid energy storage mechanism and reveal an improved Li+ diffusion coefficient (from 3.47 × 10-11 to 2.85 × 10-9 cm2 s-1). Ex-situ characterization confirms the crystal phase change of micron-sized Si and the formation of a stable LiF-rich SEI. Theoretical calculations support these findings by demonstrating an enhancement in the adsorption ability of Si to Li+ (from -0.89 to -0.97 eV) and a reduction in the energy migration barrier (from 0.35 to 0.18 eV). Additionally, practical Li x Si powder is shown to increase the ICE of full cells from 67.4 % to 87.9 %. Furthermore, a pouch cell utilizing the prelithiated P-Si@rGO@C anode paired with LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM111) cathode delivers a high initial reversible capacity of 7.2 mAh and 76.8 % capacity retention after 100 cycles. This work provides insights into the application of commercial silicon-aluminum alloy powder in the anode of high-energy LIBs. [ABSTRACT FROM AUTHOR]

Photocatalytic solar‐to‐fuel conversion over metal halide perovskites (MHPs) has recently attracted much attention, while the roles of defects in MHPs are still under debate. Specifically, the mainstream viewpoint is that the defects are detrimental to photocatalytic performance, while some recent studies show that certain types of defects contribute to photoactivity enhancement. However, a systematic summary of why it is contradictory and how the defects in MHPs affect photocatalytic performance is still lacking. In this review, the innovative roles of defects in MHP photocatalysts are highlighted. First, the origins of defects in MHPs are elaborated, followed by clarifying certain benefits of defects in photocatalysts including optical absorption, charge dynamics, and surface reaction. Afterward, the recent progress on defect‐related MHP photocatalysis, i.e., CO2 reduction, H2 generation, pollutant degradation, and organic synthesis is systematically discussed and critically appraised, putting emphasis on their beneficial effects. With defects offering peculiar sets of merits and demerits, the personal opinion on the ongoing challenges is concluded and outlining potentially promising opportunities for engineering defects on MHP photocatalysts. This critical review is anticipated to offer a better understanding of the MHP defects and spur some inspiration for designing efficient MHP photocatalysts. [ABSTRACT FROM AUTHOR]

Single molecules, the smallest independently stable units in the material world, serve as the fundamental building blocks of matter. Among different branches of single-molecule sciences, single-molecule chemical reactions, by revealing the behavior and properties of individual molecules at the molecular scale, are particularly attractive because they can advance the understanding of chemical reaction mechanisms and help to address key scientific problems in broad fields such as physics, chemistry, biology and materials science. This review provides a timely, comprehensive overview of single-molecule chemical reactions based on various technical platforms such as scanning probe microscopy, single-molecule junction, single-molecule nanostructure, single-molecule fluorescence detection and crossed molecular beam. We present multidimensional analyses of single-molecule chemical reactions, offering new perspectives for research in different areas, such as photocatalysis/electrocatalysis, organic reactions, surface reactions and biological reactions. Finally, we discuss the opportunities and challenges in this thriving field of single-molecule chemical reactions. [ABSTRACT FROM AUTHOR]

The potential energy surfaces for the reactions of 1,3‐butadiene with 2‐hydroxythioacrolein and 2‐aminoacrolein exhibit ambimodal transition states leading to both dipolar (4 + 3) and Diels–Alder (4 + 2) cycloaddition products, thereby demonstrating a post transition state bifurcation feature. We have investigated the bifurcation dynamics of these reactions using three molecular dynamics (MD) methods: quasi‐classical trajectory, classical MD, and ring‐polymer MD simulations. The trajectory calculations were performed with the semiempirical GFN2‐xTB method with the element‐specific parameters optimized to reproduce the density‐functional theory calculations. The effect of water solvation was examined using an implicit solvation model, revealing significant differences in bifurcation dynamic between gas‐phase and solution‐phase reactions. Nuclear quantum effects were found to play a crucial role in the proton‐transfer process from the (4 + 3) intermediate to the (4 + 3) product in the case of the 2‐aminoacrolein reaction. [ABSTRACT FROM AUTHOR]

Increasing the active site of redox reactions on the surface of photocatalysts and accelerating the separation and transfer of photogenerated electron‐hole pairs are effective methods to improve the hydrogen evolution of composite photocatalysts. Non‐precious metal Ni photo‐deposition is anchored in situ on the ZnIn2S4 surface to generate the cocatalyst Ni(OH)2, which improves the photocatalytic hydrogen evolution performance of the composite sample. Under visible light irradiation, the ZnIn2S4 semiconductor stimulates photon‐generated carriers. Ni2+ acts as the defect center of photogenerated electron‐hole pairs to promote the separation of carriers. It serves as the capture site of light‐generated holes to reduce the carrier recombination rate so that the light‐generated electrons on the ZnIn2S4 surface promote H+ reduction in H2. Ni(OH)2 provides the active site for oxidation reaction on the surface of semiconductor materials, allowing the carrier to be consumed faster and improving the photocatalytic stability of semiconductor materials. The addition of 2 wt% Ni2+ resulted in a hydrogen evolution rate of 10 066 µmol·g−1 ·h−1 for ZnIn2S4/Ni(OH)2, which was 2.5 times higher than that of pure ZnIn2S4. This paper presents a reference case for enhancing the stability of sulfide to promote its photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

Substitute Natural Gas (SNG) is receiving discernible attention as a fuel for the next generations because of the growing energy demand, and fossil fuels are depleting. On the other hand, CO2 emissions are already increasing, so catalytic conversion of CO2 to SNG is a promising way to reduce atmospheric CO2. However, CO2 conversion is not so easy because of its stable properties. So, there is a need for a suitable catalyst that can solve problems such as CO2 conversion, CH4 yield, catalyst deactivation and related issues. Here, we report the effect of the catalyst preparation method and the effect of precipitating agents on the problems mentioned earlier. The 5 series of Al2O3-supported Ni-based and Ni–Fe bimetallic catalysts are prepared by impregnation and coprecipitation methods and characterized by H2-TPR, XRD, H2-TPD, and CO2-TPD, NH3-TPD techniques. The reactions are carried out with TPSR by using a pulse injection technique, which showed a range of CH4 formation and CO2 conversion with a CO2:H2 ratio of 1:4. The 15(Ni–Fe)/Al2O3 showed almost 2 times better conversion and 1.5 times yield at a lower temperature (300 °C) compared to the other prepared catalysts. These findings are promising and suggest that Ni–Fe catalysts prepared by coprecipitation method are favoured for SNG production and could lead to more efficient and cost-effective process development. [ABSTRACT FROM AUTHOR]

This investigation examines the dynamic behavior of the nodular graphite structure in ductile cast iron at elevated temperatures during the recycling process. It comprises a systematic analysis of the impact of high temperature on the change in chemical composition, followed by a set of examinations of the nodular graphite structure dissolution mechanism at the early phase of the remelting process. The results indicate that prolonged holding at higher temperatures affects the carbon or silicon concentration due to oxidation, which correlates with the operating temperature and the dynamic concentration proportion of those two main alloying elements. It is also substantiated that the dissolution of nodular graphite, the only carbon source during the ductile cast iron remelting process, does not occur primarily in the liquid state but has already started during the solid phase because of austenitization. This dissolution is governed mainly by a surface reaction, as indicated by the residual graphite structure with preserved nonmetallic nuclei. Hence, this approach also provides an alternative method for observing the nodular graphite core by intentionally partially dissolving the graphite structure. [ABSTRACT FROM AUTHOR]

Cobalt-based catalysts exhibit excellent reactivity and carbon chain growth capability in the Fischer-Tropsch synthesis reaction, and their catalytic performance is closely related to the reduction degree and size of metal Co particles. Regulating the reduction degree and dispersion degree of metal Co by adding promoters is an important way to enhance their catalytic performance in Fischer-Tropsch synthesis reaction. By using SiC as a support with chemical inertness and good thermal conductivity, and adding a small amount of nanodiamonds (NDs) with rich surface functional groups as structural regulators, the dispersion degree and reduction degree of Co species in the catalyst were effectively improved, and its catalytic performance in Fischer-Tropsch synthesis reaction was enhanced. The results of N2 physical adsorption/desorption show that the addition of NDs has little effect on the parameters such as specific surface areas and pore sizes of the catalysts. The results of CO chemisorption show that the addition of an appropriate amount of NDs promotes the dispersion of active metal Co in the catalysts, increases the surface area of metal Co and provides more active sites for the Fischer-Tropsch synthesis reaction. The results of transmission electron microscopy (TEM) show that after the addition of NDs to Co/SiC (m(NDs):m(SiC) = 1.0%), the particle sizes of metal Co in the catalysts are reduced, and NDs are uniformly dispersed on the catalyst surface. The results of H2-temperature programmed reduction (H2-TPR) and CO-H2-temperature programmed surface reaction (CO-H2-TPSR) show that the addition of NDs reduces the reduction temperature of Co3O4 to metal Co and promotes the reduction of Co3O4 and the activation of CO. Compared with the Co/SiC catalyst, the NDs-modified Co/1.0NDs-SiC (W(Co) = 10%, OT(NDS):M(SiC) = 1.0%) catalyst exhibits an increase of CO conversion rate from 15.6% to 29.0%, and the selectivity of C5+ hydrocarbon products still maintains at above 75%, and shows stable operation and no significant deactivation for 70 h. The above results can provide a new research idea for the development of efficient catalysts modified with nanocarbon materials in Fischer-Tropsch synthesis reaction. [ABSTRACT FROM AUTHOR]

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Methane catalytic combustion, a method for efficient methane utilization, features high energy efficiency and low emissions. The key to this process is the development of highly active and stable catalysts. This study involved the synthesis of a range of catalysts, including NiO/CeO2, NiO–M/CeO2, and NiO-Ba/CeO2. In order to modify the NiO/CeO2 catalysts to improve their catalytic activity, various alkaline earth metal ions were introduced, and the catalysts were characterized to evaluate the impact of different alkaline earth metal ion doping. It was found that the introduction of Ba as a dopant yielded the highest catalytic activity among the dopants tested. Based on this, the influence of the impregnation sequence, the Ba loading amount, and other factors on the catalytic activity of the NiO/CeO2 catalysts doped with Ba were investigated, and comprehensive characterization was conducted using a variety of analytical techniques, including N2 adsorption/desorption, X-ray diffraction, Fourier transform infrared, hydrogen temperature-programmed reduction, methane temperature-programmed surface reaction, and oxygen temperature-programmed oxidation. The H2–TPR characterization results suggest that Ba introduction partially enhances the reducing property of NiO/CeO2 catalysts, and improves the surface oxygen activity in the catalysts. Meanwhile, the CH4–TPSR and O2–TPO results indicate that Ba introduction also boosts the bulk-phase oxygen liquidity in the catalysts, renders the migration of bulk-phase oxygen to surface oxygen, and increases the surface oxygen number in the catalysts. These results provide evidence of the effectiveness of this catalyst in methane catalytic combustion. [ABSTRACT FROM AUTHOR]

Humidity is a well-known interference factor in metal oxide (MOX) gas sensors, significantly impacting their performance in various applications such as environmental monitoring and medical diagnostics. This study investigates the effects of adsorbed water on MOX conductivity using two different materials: pure tin oxide (SnO2) and a tin–titanium–niobium oxide mixture (SnTiNb)xO2 (STN). The results reveal that (SnTiNb)xO2 sensors exhibit reduced sensitivity to humidity compared to pure tin oxide, rendering them more suitable for applications where humidity presence is critical. We aimed to shed light on a still controversial debate over the mechanisms involved in the water surface interactions for the aforementioned materials also by exploring theoretical studies in the literature. Experimental analysis involves varying temperatures (100 to 800 °C) to understand the kinetics of surface reactions. Additionally, a brief high-temperature heating method is demonstrated to effectively remove adsorbed humidity from sensor surfaces. The study employs Arrhenius-like plots for graphical interpretation, providing insights into various water adsorption/desorption phenomena. Overall, this research contributes to a deeper understanding of the role of humidity in MOX gas sensor mechanisms and offers practical insights for sensor design and optimization. [ABSTRACT FROM AUTHOR]

Surface side reactions and time‐consuming modification methods hinder the practical application of zinc‐ion batteries. This study introduces an ultrathin protection layer for the Zn anode via a rapid sputtering method. The dopants on the CN10@Zn anode create surface dipoles and local variations in charge distribution, facilitating zinc ion migration to pyrrolic nitrogen dopant sites with reduced adsorption barriers. Additionally, hydroxyl oxygen dopants enhance the hydrophilicity of the sputtering layer, forming a strong adhesion with the zinc anode and improving ion accessibility. This results in dense nucleation sites for uniform zinc deposition. Consequently, the sputtered layer achieves a Coulombic efficiency of 99.8% over 2,700 cycles in Cu||Zn cells and a lifespan of up to 2,100 h in zinc symmetric cells. When paired with Na0.65Mn2O4 cathodes, the sputtered layer retains 89% capacity over 1,000 cycles at 1 A g−1. This study presents a promising method for rapidly fabricating ultrathin electrode materials. [ABSTRACT FROM AUTHOR]

A hierarchical sea urchin-like hybrid metal oxide nanostructure of ZnO nanorods deposited on TiO2 porous hollow hemispheres with a thin zinc titanate interface layer is specifically designed and synthesized to form a combined type I straddling and type II staggered junctions. The HHSs, synthesized by electrospinning, facilitate light trapping and scattering. The ZnO nanorods offer a large surface area for improved surface oxidation kinetics. The interface layer of zinc titanate (ZnTiO3) between the TiO2 HHSs and ZnO nanorods regulates the charge separation in a closely coupled hierarchy structure of ZnO/ZnTiO3/TiO2. The synergistic effects of the improved light trapping, charge separation, and fast surface reaction kinetics result in a superior photoconversion efficiency of 1.07% for the photoelectrochemical water splitting with an outstanding photocurrent density of 2.8 mA cm−2 at 1.23 V versus RHE. [ABSTRACT FROM AUTHOR]

Operando decoding of the key parameters of photo‐electric catalysis provides reliable information for catalytic effect evaluation and catalytic mechanism exploration. However, to capture the details of surface‐localized and rapid chemical and thermal events at the nanoscale in real‐time is highly challenging. A promising approach based on a lab‐around‐microfiber sensor capable of simulating photo‐electric catalytic reactions on the surface of optical fibers as well as monitoring reactant concentration changes and catalytic heat generation processes is demonstrated. Due to the penetration depth of submicron size and the fast response ability of the evanescent field, the lab‐around‐microfiber sensor overcame the difficulty of reading instantaneous surface parameters in the submicron range. This sensor operando dismantled the changes in reactant concentration and temperature on the catalyst surface induced by light and voltage, respectively. It also decoded the impact of catalyst composition on the adsorption efficiency and catalytic efficiency across various wavelengths and determined the synchronized occurrence of pollutant degradation and catalytic thermal effects. Stable correlations between the real‐time parameters and catalytic activities are obtained, helping to provide a basic understanding of the catalytic process and mechanism. This approach fills an important gap in the current monitoring methods of catalytic processes and heat production. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures that pair materials with diverse properties enable various quantum phenomena. However, the direct growth of vdW heterostructures is challenging. Modification of the surface layer of quantum materials to introduce new properties is an alternative process akin to solid state reaction. Here, vapor deposited transition metals (TMs), Cr and Mn, are reacted with Bi2Se3 with the goal to transform the surface layer to XBi2Se4 (X = Cr, Mn). Experiments and ab initio MD simulations demonstrate that the TMs have a high selenium affinity driving Se diffusion toward the TM. For monolayer Cr, the surface Bi2Se3 is reduced to Bi2‐layer and a stable (pseudo) 2D Cr1+δSe2 layer is formed. In contrast, monolayer Mn can transform upon mild annealing into MnBi2Se4. This phase only forms for a precise amount of initial Mn deposition. Sub‐monolayer amounts dissolve into the bulk, and multilayers form stable MnSe adlayers. This study highlights the delicate energy balance between adlayers and desired surface modified layers that governs the interface reactions and that the formation of stable adlayers can prevent the reaction with the substrate. The success of obtaining MnBi2Se4 points toward an approach for the engineering of other multicomponent vdW materials by surface reactions. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures that pair materials with diverse properties enable various quantum phenomena. However, the direct growth of vdW heterostructures is challenging. Modification of the surface layer of quantum materials to introduce new properties is an alternative process akin to solid state reaction. Here, vapor deposited transition metals (TMs), Cr and Mn, are reacted with Bi2Se3 with the goal to transform the surface layer to XBi2Se4 (X = Cr, Mn). Experiments and ab initio MD simulations demonstrate that the TMs have a high selenium affinity driving Se diffusion toward the TM. For monolayer Cr, the surface Bi2Se3 is reduced to Bi2‐layer and a stable (pseudo) 2D Cr1+δSe2 layer is formed. In contrast, monolayer Mn can transform upon mild annealing into MnBi2Se4. This phase only forms for a precise amount of initial Mn deposition. Sub‐monolayer amounts dissolve into the bulk, and multilayers form stable MnSe adlayers. This study highlights the delicate energy balance between adlayers and desired surface modified layers that governs the interface reactions and that the formation of stable adlayers can prevent the reaction with the substrate. The success of obtaining MnBi2Se4 points toward an approach for the engineering of other multicomponent vdW materials by surface reactions. [ABSTRACT FROM AUTHOR]

Green corrosion inhibitors have shown considerable promise as a viable alternative to synthetic inhibitors for preventing corrosion in various applications. In this study, the aquatic plant Eichhornia crassipes (water hyacinth), native to the Pantanal region, was evaluated for its potential as a green corrosion inhibitor for AISI 1005 steel in an electrolyte containing 0.01 mol L-1 HCl. The plant extraction was conducted using both maceration and ultrasound with the electrolyte. The study employed open circuit potential (OCP), potentiodynamic polarization (PDP) using electrochemical techniques, and weight loss (WL) tests were performed. The results indicated a reduction in the rate of corrosive reactions on the steel surface, particularly in cathodic reactions, with corrosion inhibition efficiency reaching nearly 90 %. [ABSTRACT FROM AUTHOR]

Low molecular weight organic acids often influence the surface reactions (adsorption/ precipitation) of minerals, which in turn affect the stability of elemental transport in environmental geochemical processes. The effect of malic acid on calcite-fluorine adsorption/ precipitation reactions was investigated. The results show that at the initial pH of 7.7 and lower F concentrations (5 mg·L-1¯), as the concentration of malic acid increases, its surface adsorption capacity becomes stronger and exhibits the inhibitory effects on F removal; at the F concentrations of 25 or 60 mg·L-1, the dominant mechanism of F removal is CaF2 precipitation; the intervention of malic acid shows little inhibition of the CaF, precipitation reaction; the stronger adsorption reaction of malic acid results in an increase of pH and a decrease in Ca concentration. At the initial pH of 8. 3 and low F concentration (<20 mg·L-1), malic acid still inhibits F removal through its competitive adsorption; as the concentration of malic acid increases, its effect of complexation with Cat results in a constant increase in pH and Ca concentration; at the medium F concentration of 60 mg·L-1, the dominant mechanism of F removal has been shifted to CaF2 precipitation; 20 mg·L-1 malic acid has inhibited it, and as the malic acid continues to increase, the pH value decreases and then increases, and the Ca concentration continues to increase, highlighting the effect of the malic acid complexation reaction; At high F concentration of 100 mg·L-1, 100 mg·L-1 malic acid greatly inhibits the CaF2 precipitation reaction, corresponding to a pH value that do not exceed that of the malic acid- free condition; the corresponding Ca concentration is still lower than its blank background value. implying the dominance of the CaF2 precipitation reaction. At the initial pH of 8.7, malic acid has a weak inhibition to F removal at low F concentration (5 mg·L-1); however, as the concentration of malic acid increases, the effect of its complexation reaction becomes much clearer, which results in a significant increase in both pH and Ca concentration; at high F concentration of 240 mg·L-1, the dominant mechanism for F removal is the CaF2 precipitation reaction, which is inhibited with increasing malic acid concentration, with increasing Ca concentration showing the effect of malic acid complexation, and decreasing pH values indicating the dominance of the CaF2 precipitation reaction. This study is important for the stability assessment of calcite minerals in organic acid-rich environments, and also provides a reference for the study of fluorine transport transformation on other minerals. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting into hydrogen production provides a new avenue to produce clean chemical fuels. However, developing high‐efficiency photocatalytic materials still remains a challenge till now. Herein, multiobjective‐optimization MoS2/Cd‐ZnIn2S4/CdS (MS/CZIS/CS) composites are successfully constructed by an in situ structure‐tailored technique. Benefiting from the synergistic feature integrating sulfur vacancy, II‐type CZIS/CS heterojunction and Schottky‐type MS/CS heterojunction, such composites not only effectively steer photogenerated carrier transfer but also markedly expedite surface reaction kinetics for hydrogen reduction reaction. As a result, an optimal hydrogen evolution rate of 11.49 mmol g−1 h−1 is achieved over the MS/CZIS/CS catalysts, which is approximately 4.79 times higher than that of pristine ZIS (2.40 mmol g−1 h−1). This work provides some new inspirations for the steering of carrier transfer and the design of multiobjective‐optimization photocatalysts with high efficiency. [ABSTRACT FROM AUTHOR]

Efficient separation of photogenerated carriers and surface reactions is the crucial factor in achieving successful photocatalytic water splitting. Herein, a novel Pt@Co-T@T@M hollow sphere was prepared by a template-assisted method. Pt was anchored on the inner surface of Co-doped TiO2 shell, serving as electron collectors and active sites for reduction reaction, while MnOX was immobilized on the outer surface of TiO2 shell for oxidation reaction. Under simulated one-sun (AM 1.5G) illumination, the as-prepared Pt@Co-T@T@M hollow spheres exhibited a remarkable hydrogen evolution rate of 7.304 mmol g−1 h−1, which is 114 times higher than that of T@T hollow spheres. The exceptional photocatalytic water-splitting performance is attributed to the synergistic effect between homojunction and spatial dual-cocatalyst, which promotes enhanced spatial separation of photogenerated carriers and reduces recombination. This study highlights the importance of precise and rational control over photocatalyst structure for achieving highly efficient water splitting. [ABSTRACT FROM AUTHOR]

The study delves into the use of the thiol-yne click reaction to enhance (bio)conjugation methodologies, particularly focusing on immobilizing biomolecules onto PLLA surfaces. The thiol-yne click reaction, known for its efficiency, selectivity, and versatility in forming carbon-sulfur bonds under mild conditions without transition metal catalysts, is explored for conjugating the fluorophore dansyl onto PLLA surfaces. This approach aims to broaden bioconjugation strategies beyond traditional methods like the Michael-type reaction, expanding their applicability to diverse biomolecules. Utilizing a photoinitiator and specific light for photo-immobilization, the thiol-yne click reaction offers spatial and temporal control, with the absence of transition metal catalysts mitigating concerns of cytotoxicity and metal contamination, rendering it suitable for biomedical applications. The objectives of this research encompass demonstrating the feasibility of the thiol-yne click reaction for surface functionalization and enriching bioconjugation strategies for tailoring PLLA surfaces, ultimately advancing biomedical technologies through precise control over surface properties and functionality. For this purpose, PLLA surfaces were activated through hydrolysis and amidation to introduce the activated alkyne moiety (PLLA-Alkyne), followed by photo-induced dansyl immobilization (PLLA-Dns) with Irgacure 651. Various surface characterization techniques, including SEM, WCA, XPS, ATR-FTIR, and fluorescence microscopy and spectroscopy, validated the successful conjugation. This metal-free method preserves the material's bulk properties while enabling thiol-containing molecule immobilization. [ABSTRACT FROM AUTHOR]

The cyclic two-step process, comprised of energetic H2 plasma followed by HF wet clean or in situ NF3 plasma, demonstrates Si3N4 layer-by-layer removal capability exceeding 10 nm per cycle, surpassing typical atomic layer etch methods by an order of magnitude. In this paper, we investigated the surface reaction mechanisms via first principle density functional theory simulations and surface analysis. The results unveiled that energetic H2 plasma, in the first step, selectively removes nitrogen (N) in preference to silicon (Si), generating ammonia (NHx) and transforming Si3N4 into SiON upon exposure to air, which becomes removable by HF wet clean in the second step. For the second step employing in situ NF3 plasma, it further leverages H-passivated surfaces to enhance NF3 dissociation and provide alternative reaction pathways to yield volatile byproducts such as SiHF3 and SiFx, thereby significantly improving nitride removal efficiency. [ABSTRACT FROM AUTHOR]

Regulating Ni active sites toward the formation of target product is of great importance for designing high‐performance cost‐effective catalysts for catalytic semi‐hydrogenations but remains challenging. Herein, we report the fabrication of NiSb intermetallic catalyst via structural transformation from a layered double hydroxides precursor for boosting propyne semi‐hydrogenation. Systematic characterizations, including x‐ray diffraction, atomic‐resolution electron microscopy, and x‐ray absorption spectroscopy, provide evidence for the formation of P63/mmc NiSb intermetallic phase in the synthesized NiSb catalyst. The host Ni active sites are demonstrated to be isolated by the high‐electronegativity p‐block guest Sb sites, which deliver remarkably high selectivity to target propene, that is, up to propene selectivity of 96% at nearly full propyne conversion. Temperature‐programmed surface reaction and temperature‐programmed desorption measurements combined with theoretical calculations unravel that the excellent selectivity originates from kinetically more favorable desorption of propene than its hydrogenation to propane on the regulated Ni active sites. [ABSTRACT FROM AUTHOR]

The dynamics of many-body fermionic systems are important in problems ranging from catalytic reactions at electrochemical surfaces to transport through nanojunctions and offer a prime target for quantum computing applications. Here, we derive the set of conditions under which fermionic operators can be exactly replaced by bosonic operators that render the problem amenable to a large toolbox of dynamical methods while still capturing the correct dynamics of n-body operators. Importantly, our analysis offers a simple guide on how one can exploit these simple maps to calculate nonequilibrium and equilibrium single- and multi-time correlation functions essential in describing transport and spectroscopy. We use this to rigorously analyze and delineate the applicability of simple yet effective Cartesian maps that have been shown to correctly capture the correct fermionic dynamics in select models of nanoscopic transport. We illustrate our analytical results with exact simulations of the resonant level model. Our work provides new insights as to when one can leverage the simplicity of bosonic maps to simulate the dynamics of many-electron systems, especially those where an atomistic representation of nuclear interactions becomes essential. [ABSTRACT FROM AUTHOR]

We present a probabilistic microkinetic modeling (MKM) framework that incorporates the short-ranged order (SRO) evolution for adsorbed species (adspecies) on a catalyst surface. The resulting model consists of a system of ordinary differential equations. Adsorbate–adsorbate interactions, surface diffusion, adsorption, desorption, and catalytic reaction processes are included. Assuming that the adspecies ordering/arrangement is accurately described by the SRO parameters, we employ the reverse Monte Carlo (RMC) method to extract the relevant local environment probability distributions and pass them to the MKM. The reaction kinetics is faithfully captured as accurately as the kinetic Monte Carlo (KMC) method but with a computational time requirement of few seconds on a standard desktop computer. KMC, on the other hand, can require several days for the examples discussed. The framework presented here is expected to provide the basis for wider application of the RMC-MKM approach to problems in computational catalysis, electrocatalysis, and material science. [ABSTRACT FROM AUTHOR]

The development of advanced layered Ni-rich cathodes is essential for high-energy lithium-ion batteries (LIBs). However, the prevalent Ni-rich cathodes are still plagued by inherent issues of chemomechanical and thermal instabilities and limited cycle life. For this, here, we introduce an efficient approach combining single-crystalline (SC) design with in situ high-entropy (HE) doping to engineer an ultrahigh-Ni cobalt-free layered cathode of LiNi0.88Mn0.03Mg0.02Fe0.02Ti0.02Mo0.02Nb0.01O2 (denoted as HE-SC-N88). Thanks to the SC- and HE-doping merits, HE-SC-N88 is featured with a grain-boundary-free and stabilized structure with minimal lattice strain, preventing mechanical degradation, reducing surface parasitic reactions, and mitigating oxygen loss. Accordingly, our HESC-N88 cathode demonstrates exceptional electrochemical properties particularly with prolonged cycling stability under strenuous conditions in both half and full cells, and the delayed O loss-induced phase transitions upon heating. More meaningfully, our design of HE doping in redefining the ultrahigh-Ni Co-free SC cathodes will make a tremendous progress toward industrial application of next-generation LIBs. [ABSTRACT FROM AUTHOR]

Solar energy can be utilized in photocatalysis technology to realize light‐driven hydrogen peroxide (H2O2) production, a green chemical synthesis route. Designing high‐performance photocatalysts is critical to achieving practical solar H2O2 production. During the past decade, significant research progress is made in photocatalytic materials for H2O2 production. Particularly 2D materials‐based photocatalysts stand out due to their unique physical and chemical properties. This review highlights the intricate relationship between 2D material innovation and photochemical H2O2 production. It starts with the fundamental principles of photochemical H2O2 generation, focusing on crucial steps such as photon absorption, carrier dynamics, surface reactions, and the challenges that 2D materials can solve at each step. Then, various 2D materials‐based photocatalysts for solar H2O2 production are introduced in detail. Engineering strategies to optimize the photocatalytic performance are discussed afterward. Finally, the challenges and future opportunities for designing 2D materials‐based photocatalysts for solar H2O2 production are outlined. This review is expected to inspire the engineering of 2D materials‐based photocatalysts for the green synthesis of H2O2 and the conversion of solar energy to other chemicals. [ABSTRACT FROM AUTHOR]

Photocatalysis represents a sustainable strategy for addressing energy shortages and global warming. The main challenges in the photocatalytic process include limited light absorption, rapid recombination of photo-induced carriers, and poor surface catalytic activity for reactant molecules. Defect engineering in photocatalysts has been proven to be an efficient approach for improving solar-to-chemical energy conversion. Sulfur vacancies can adjust the electron structure, act as electron reservoirs, and provide abundant adsorption and activate sites, leading to enhanced photocatalytic activity. In this work, we aim to elucidate the role of sulfur vacancies in photocatalytic reactions and provide valuable insights for engineering high-efficiency photocatalysts with abundant sulfur vacancies in the future. First, we delve into the fundamental understanding of photocatalysis. Subsequently, various strategies for fabricating sulfur vacancies in photocatalysts are summarized, along with the corresponding characterization techniques. More importantly, the enhanced photocatalytic mechanism, focusing on three key factors, including electron structure, charge transfer, and the surface catalytic reaction, is discussed in detail. Finally, the future opportunities and challenges in sulfur vacancy engineering for photocatalysis are identified. [ABSTRACT FROM AUTHOR]

An interfacial C-S bond bridged ZnS/C 3 N 5 S-scheme heterojunction was constructed for photocatalytic H 2 evolution. Benefiting from the interfacial covalent bond, enhanced internal-electric-field strength, and accelerated surface photocatalytic reaction, the photocatalytic H 2 production of ZnS/C 3 N 5 was 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [Display omitted] • C-S bond is susceptive to preparation temperatures, and it is broken above 300 °C. • C-S bond promotes e − separation and improves H 2 O adsorption and activation behaviors. • IEF strength of ZnS/C 3 N 5 with opposite direction is 2.6 times than that of ZnS/C 3 N 4. • e − transfer respectively follow S-scheme and type-II pathway in ZnS/C 3 N 5 and ZnS/C 3 N 4. • H 2 yield of ZnS/C 3 N 5 is 3.2 and 2.5 times than ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S. An interfacial C-S bond bridged ZnS/C 3 N 5 heterojunction was constructed for photocatalytic H 2 evolution. Different from traditional type-II ZnS/C 3 N 4 heterojunction, the electron transfer followed S-scheme pathway, due to opposite internal-electric-field (IEF) directions in these two heterojunctions. The C-S bond formation was carefully investigated, and they were susceptive to the preparation temperatures. In photocatalytic reaction, C-S bond was functioned as the "high-speed channel" for electron separation and transfer, and the IEF strength in ZnS/C 3 N 5 was 1.86 × 108 V/m, 2.6 times higher than that in ZnS/C 3 N 4. Moreover, the C-S bond also altered the surface molecular structure of ZnS/C 3 N 5 , and hence the surface reaction was accelerated via improving H 2 O adsorption and activation behaviors. Benefiting from the S-scheme pathway, enhanced IEF strength, and accelerated surface reaction, the photocatalytic H 2 production over ZnS/C 3 N 5 reached up to 20.18 mmol/g/h, 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [ABSTRACT FROM AUTHOR]

Regulating bulk charge carrier transfer and surface catalytic reaction kinetics is thought a big challenge to photoelectrochemical (PEC) water splitting. Herein, the dual sites of CoNiP are delicately introduced into ZnIn2S4 (RZIS‐CoNiP) nanosheet arrays via a defect anchoring method. The paving [S─Ni─P] interfacial bond like a "bridge" can greatly reduce the phase resistance, improve the charge separation and migration, and promote the surface oxygen evolution reaction (OER) reaction. As expected, the optimized RZIS‐CoNiP photoanode achieved a maximum photocurrent density of 4.77 mA cm−2 at 1.23 V versus reversible hydrogen electrode (RHE) in neutral electrolyte solution without the presence of any sacrificial agents, which is ≈12 times higher than that of the pristine ZnIn2S4 under AM 1.5G illumination. And the amount of oxygen evolution for the RZIS‐CoNiP photoanode is as high as 21.9 µmol in 3 h. Transient spectroscopy measurements and density functional theory (DFT) calculations in situ discovered the mechanism of defect anchoring [S─Ni─P] bond on regulating charge transfer and surface reaction processes. This work provides a feasible anchoring interface route through defect engineering to regulate charge carrier transfer for PEC water splitting. [ABSTRACT FROM AUTHOR]

Most modern catalysts are based on precious metals and rear-earth elements, making some of organic synthesis reactions economically insolvent. Density functional theory calculations are used here to describe several differently oriented surfaces of the higher tungsten boride WB5-x, together with their catalytic activity for the CO oxidation reaction. Based on our findings, WB5-x appears to be an efficient alternative catalyst for CO oxidation. Calculated surface energies allow the use of the Wulff construction to determine the equilibrium shape of WB5-x particles. It is found that the (010) and (101) facets terminated by boron and tungsten, respectively, are the most exposed surfaces for which the adsorption of different gaseous agents (CO, CO2, H2, N2, O2, NO, NO2, H2O, NH3, SO2) is evaluated to reveal promising prospects for applications. CO oxidation on B-rich (010) and W-rich (101) surfaces is further investigated by analyzing the charge redistribution during the adsorption of CO and O2 molecules. It is found that CO oxidation has relatively low energy barriers. The implications of the present results, the effects of WB5-x on CO oxidation and potential application in the automotive, chemical, and mining industries are discussed. [ABSTRACT FROM AUTHOR]

The study was carried out by LEED, AES, EELS, and AFM methods. Films of Fe/Si(001)2 × 1 were obtained at substrate temperatures of 30°C and source temperatures of 1250°C. Wetting layer (WL) Fe on Si(001)2 × 1 was formed by two-stage annealing at temperatures and thicknesses of 500 and 250°C and 1 monolayer (ML) and 3 ML, respectively. Analysis and interpretation of the data obtained, taking into account possible reaction patterns, showed that after annealing at 1 ML thickness, the Fe composition corresponded to 2 ML Si/Fe. Further, at 2 ML, it changed to Fe/Si/Fe, at 3 ML, it changed to Fe–FeSi, and after annealing, to FeSi. At 4 ML, there was formation of FeSi/FeSi2 film. And, further, at 7 ML and 10 ML, the composition of the films became Fe3Si/FeSi2 and, respectively, Fe/Fe3Si/FeSi2. At the same time, the upper Fe3Si layers were coated with 0.6 ML and the Fe layers with 0.3 ML of segregated Si atoms, which number increased, after annealing at 250°C, to 0.6 ML in the latter case. In the obtained Fe film, the size and average grain height were 10−20 nm and, respectively, ∼0.4 nm. [ABSTRACT FROM AUTHOR]

The combustion characteristics of micro-combustors significantly impact the performance of micro-thermophotovoltaic (MTPV) systems. This study aims to investigate the effects of sinusoidal-shaped walls and catalyst segmentation on flame stability and combustion performance in a micro-combustor by using numerical methods. The numerical simulation with detailed gas-phase and surface reaction mechanisms is reliable, as the results of numerical simulation align with experimental data. The results show that the interplay between flame stability and sinusoidal-shaped walls is crucial, particularly because of the cavities formed by the sinusoidal-shaped walls of the micro-combustor. The gas-phase ignition position of the sinusoidal-shaped wall combustor moves upstream by 0.050 m compared to the planar-wall combustor, but the flame is stretched. The catalyst segments coated on the crest can shorten the flame length and increase the average temperature by a maximum 62 K, but delay the gas-phase ignition. Conversely, catalyst segments coated on the trough can advance ignition, but this results in flame elongation and a decrease in the average temperature. The rational combination of catalyst segmentation and sinusoidal-shaped walls facilitates moving the ignition position upstream by a maximum of 0.065 m while substantially reducing the length of the combustor required for complete fuel conversion by more than 60%. These attributes are highly beneficial for improving efficiency and minimizing the length of the micro-combustor for MTPV application. [ABSTRACT FROM AUTHOR]

Numerical modeling of the high-speed flow of a multicomponent dissociated gas around a blunt body was carried out for the flow regime corresponding to the thermally stressed point of the gliding trajectory of entry into the Earth's atmosphere in the surface temperature range of 800–2000 K. As boundary conditions, a stage-by-stage model of heterogeneous catalysis of the interaction of dissociated air with the thermal protection material SiO 2 was used, previously developed by the authors on the basis of transition state theory and quantum mechanical calculations. The dependence of the modes of heterogeneous chemical reactions on the surface temperature and the density of surface adsorption centers and their influence on the chemical composition of the shock layer and the convective heat flux to the streamlined surface are analyzed. The contributions of individual mechanisms of heterogeneous recombination to the total rate of formation of molecules on the surface are estimated. The possibility of using the density of adsorption sites as an effective parameter when setting boundary conditions on a real thermal protection surface in flow problems is shown. • The influence of heterogeneous processes on the structure and chemical composition of the shock layer was studied. • The contribution to surface recombination of different mechanisms of heterogeneous catalysis was analyzed. • A significant influence of the number of adsorption sites on the regime of surface reactions has been shown. [ABSTRACT FROM AUTHOR]

A surface chemical reaction network (sCRN, Qian and Winfree in DNA Computing and Molecular Programming: 20th International Conference, DNA 20, Kyoto, Japan, September 22–26, 2014. Proceedings 20. Springer, 2014) is an emergent paradigm for molecular programming, in which a chemical molecule is placed at each site of a lattice, and each molecule may undergo either bi-molecular reactions associated with one of the nearest molecules or uni-molecular reactions autonomously. The lattice structure as well as the localized reactions between molecules facilitate an effective formalization of sCRNs in the framework of cellular automata. This formalism not only allows a systematic evaluation of the complexity of a sCRN, but also enables a formal approach to reduce the model's complexity for the sake of improving its effectiveness. To this end, this paper proposes a new sCRN model that has less complexity measured in terms of the numbers of both cell states and transition rules. Especially, universality of computations will be shown by implementing all asynchronous circuits, including the well-known full-adder, into the sCRN. The decreased complexity may enhance the feasibility of the proposed sCRN model for physical implementation. [ABSTRACT FROM AUTHOR]

This research aims to investigate the potential of novel CaF2 − CaO − Na2O − B2O3−SiO2 glass systems and converted to bioactive glass-ceramics. The study involves examining the effects of different heat treatment temperatures and immersion periods, with the goal of exploring these materials as viable alternatives for various biomedical applications. A typical melt-quenching technique was used to synthesize the glass samples, followed by a controlled heat treatment. The main crystalline phases are cuspidine and wollastonite, which have the potential to promote bioactivity, especially in dental and bone-related applications. The sample heat-treated at 700 °C showed an increased microhardness and fracture toughness by more than 116% and 36%, compared to the initial value. Furthermore, the increase in pH and the observed weight loss/gain demonstrated the reactivity of the samples with the phosphate buffer-saline medium, indicating their bioactive properties. Remarkably, the microhardness and fracture toughness exhibited notable improvements after 14 days of immersion, with an enhancement of 4.71% and 4.66%, highlighting their potential durability and longevity in high-strength dental crown applications. Consequently, this research presents a promising method for developing sustainable novel glass and glass-ceramic materials devoid of phosphates. These materials boast enhanced mechanical properties while preserving bioactivity, making them well-suited for dental implants and restorative purposes. [ABSTRACT FROM AUTHOR]

Single-atom photocatalysts exhibit outstanding performance in energy and environmental photocatalysis, due to their exceptional capabilities in enhancing light-harvesting, charge transfer dynamics, and surface reactions. The key to preparing single-atom photocatalysts lies in developing an appropriate metal-support that can prevent aggregation or sintering during synthetic procedures. In this work, a Co(II)-urea complexe in-situ formed in melamine was employed as single-atom Co precursors to synthesize an efficient single-atom Co decorated P doped g-C3N4 (Co/PCN) photocatalyst. The high-angle annular dark field transmission electron microscope (HAADF-TEM) results indicated abundant Co single atoms were immobilized in the g-C3N4 matrix. Under visible-light irradiation, the as-prepared photocatalysts show remarkably enhanced photocatalytic performance. Especially, loaded with 1.5 wt% single atoms Co, the optimized Co/PCN exhibits H2 evolution of 892.5 µmol g−1 h−1, which is 33 times higher than that of PCN, and even twice as much as that of Pt-loaded g-C3N4 (Pt/PCN). The enhanced photocatalytic activity is ascribed to the synergistic effect between single-atom Co and P doping, which facilitates efficient light harvesting, charge separation, and migration. It is believed that this study paves a new avenue for developing high-efficiency single-atom photocatalysts. [ABSTRACT FROM AUTHOR]

Background: Schefflera heptaphylla is a species of plant living in the forest, containing numerous bioactive compounds beneficial for human health. The efficient extraction of these bioactive compounds from the plant while minimizing losses is a currently highlighted issue. Methods: In this research, the impact of three variables: drying time (min), drying air velocity (m/s) and drying air temperature (°C) on the reactions, including loss of total phenolic (TPCL), total flavonoid content loss (TFCL) and moisture content (MC) investigation of Schefflera heptaphylla leaves was conducted using the central complex design (CCD) within the framework of the methodology reaction surface method (RSM). Result: The optimal conditions obtained from the response surface method were 48°C, 1.9 m/s and 600 min. The experimental values at the optimal conditions of TPCL, TFCL and MC are 17.22±0.20%, 14.83±0.15% and 8.47±0.12%, respectively. Crude fiber content, moisture content, total ash and total fat content of raw materials have been identified. [ABSTRACT FROM AUTHOR]

As an alternative to Li‐ion batteries, aqueous Zn batteries have gained attention due to the abundance of Zn metal, low reduction potential (–0.76 V vs. standard hydrogen electrode), and high theoretical capacity (820 mAh g–1) of multivalent Zn2+ ion. However, the growth of Zn dendrites and the formation of irreversible surface reaction byproducts pose challenges for ensuring a long battery lifespan and commercialization. Herein, the Cu foil coated with a single‐walled carbon nanotube (SWCNT) layer using a facile doctor blade casting method is utilized. The SWCNT‐coated Cu foil demonstrates a significantly longer battery lifespan compared to the bare Cu in the half‐cell tests. Through operando optical microscopy imaging, we are able to provide intuitive evidence that Zn deposition occurs between the carbon nanotube (CNT) coating and Cu substrate, in agreement with the computational results. Also, with various imaging techniques, the flat morphology and homogeneous distribution of Zn beneath the SWCNT layer are demonstrated. In addition, the full‐cell using CNT‐coated Cu exhibits a long cycle life compared to the control group, thereby demonstrating improved electrochemical performance with limited Zn for the cycling process. [ABSTRACT FROM AUTHOR]

We examine a saturated bidispersive porous medium undergoing an exothermic chemical reaction at its lower boundary. The fluid flow within this medium is modelled using the Darcy approach. While the Dufour effect is disregarded, the influence of the Soret effect is thoroughly explored. This problem represents a complex multiphysical phenomenon that integrates fluid dynamics, heat and mass transfer, chemical kinetics and thermoelectric effects. This problem finds relevance in various scientific and engineering applications, including enhanced oil recovery, chemical engineering, environmental engineering and energy systems. We introduce a complementary energy theory alongside a linear theoretical framework for the model. The Chebyshev collocation method is employed to derive both linear and nonlinear results. Our findings reveal that the effect of enhancing the Soret coefficient on the system's stability is contingent upon the boundary conditions and the Lewis number. Specifically, an increase in the Soret coefficient generally stabilises the system during stationary convection. Conversely, in scenarios where oscillatory convection prevails, a higher Soret coefficient tends to destabilise the system. [ABSTRACT FROM AUTHOR]

The market for lithium-ion batteries (LiBs) is growing rapidly, the demand for lithium (Li) in the form of lithium carbonate (Li2CO3), which is the most common lithium mineralization form, is therefore also increasing significantly. Li is conventionally extracted as Li2CO3 using sodium carbonate (Na2CO3) to precipitate Li ions in an aqueous Li solution. However, Na2CO3 can also be replaced by CO2, which highlights the potential of using CO2 as a sustainable and economically viable alternative. This review focuses on technologies that utilize CO2 for Li2CO2 precipitation. First, the use of CO2 gas and Na2CO3 as carbonate sources are compared, and the need to consider important operating conditions with CO2 bubbling are then presented. Attempts made to increase the specific surface area of the reaction surface to enhance the utilization of CO2 gas and to produce micro-sized Li2CO3 powders are then reported, and the limitations associated with CO2 gas utilization are discussed. Although CO2 precipitation has limitations in terms of efficiency, scalability, and the fine-tuning of reaction conditions, this review shows that if CO2 precipitation technology is further developed, its use could be key to extracting and recycling next-generation Li. [ABSTRACT FROM AUTHOR]

The solar‐driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo‐generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed‐linker strategy to build a donor‐acceptor‐acceptor (D–A–A) type covalent organic framework (COF) photocatalyst, FS‐OHOMe‐COF. The FS‐OHOMe‐COF structure features extended π–π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS‐OHOMe‐COF has a low exciton binding energy, long excited‐state lifetime and high photo‐stability that leads to high performance for photocatalytic H2O2 production (up to 1.0 mM h−1) with an H2O2 output of 19 mM after 72 hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192 hours of photocatalytic experiment. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) performance of photoanode is limited by the cascade-dynamic processes, mainly including light absorption, charge separation, and surface reaction. This work adopted a strategy of nanocones modification on FTO substrate (FTO-NC) to enhance light utilization and photoelectrons collection for improved PEC water splitting. Comparative studies showed that FTO-NC enhanced the light scattering, promoting the conversion process of photon to electron/hole and enlarging the effective surface area of BiVO 4 for surface reaction. Meanwhile, cooperative Mo-doping and Co-MOF decoration improved the bulk electron transportation in BiVO 4 , hole migration towards the electrode surface, and accelerated the water oxidation reaction of photogenerated holes. The photocurrent density of FTO-NC/BiVO 4 -Mo/MOFs reached 3.56 mA cm−2, 6.14 times that of pristine BiVO 4. The IPCE of FTO-NC/BiVO 4 -Mo/MOFs photoanode achieve 60% at 1.23 V vs. RHE, demonstrating a significantly enhanced light utilization performance. This work presents new insight into boosting cascade-dynamic processes through collaborative strategies for highly efficient PEC water-splitting. [Display omitted] • FTO-NC had high light scattering effect for increasing light absorption of BiVO 4. • The photocurrent of FTO-NC/BiVO 4 -Mo/MOFs was increased by 6.14 times than FTO-BiVO 4. • FTO-NC/BiVO 4 -Mo/MOFs showed 2.7-times higher η transfer than FTO-BiVO 4. [ABSTRACT FROM AUTHOR]

A method is proposed to measure the kinetics of elementary‐step reactions using reflection‐absorption infrared spectroscopy (RAIRS) by slowly ramping the sample temperature while continually collecting the interferograms, where the interferograms are post‐processed to provide temperature‐dependent spectra. Heating rates of ~10−2 K/s allow spectra to be collected so that the temperature is essentially constant for each spectrum. This strategy can allow short‐lived intermediates to be observed. The data are fit to analytical formulae similar to those used for conventional temperature‐programmed desorption and the two approaches are complementary. The method is illustrated by measuring the activation energy for the ordering of crystalline thin films and for multilayer desorption. The utility of the approach for measuring surface‐chemical processes is illustrated for the dimerization kinetics of a prochiral reactant, methyl pyruvate (CH3CCO2CH3), on Pd(111), where the monomer has been found to be more reactive than the dimer, and the decarbonylation steps of furfural (C4H3O ⋅ CHO), a product of the treatment of biomass. The results are in good agreement with cases in which there are other methods for measuring the reaction rates. The approach is also useful for establishing how accurate the results of theoretical simulations are for elementary surface reactions. [ABSTRACT FROM AUTHOR]

Highly selective etching of silicon nitride (Si3N4) and silicon dioxide (SiO2) has received considerable attention from the semiconductor community owing to its precise patterning and cost efficiency. We investigated the etching selectivity of Si3N4 and SiO2 in an NF3/O2 radio-frequency glow discharge. The etch rate linearly depended on the source and bias powers, whereas the etch selectivity was affected by the power and ratio of the gas mixture. We found that the selectivity can be controlled by lowering the power with a suitable gas ratio, which affects the surface reaction during the etching process. X-ray photoelectron spectroscopy of the Si3N4 and QMS measurements support the effect of surface reaction on the selectivity change by surface oxidation and nitrogen reduction with the increasing flow of O2. We suggest that the creation of SiOxNy bonds on the surface by NO oxidation is the key mechanism to change the etch selectivity of Si3N4 over SiO2. [ABSTRACT FROM AUTHOR]

Recent studies have shown that active colloidal motors using enzymatic reactions for propulsion hold special promise for applications in fields ranging from biology to material science. It will be desirable to have active colloids with capability of computation so that they can act autonomously to sense their surroundings and alter their own dynamics. It is shown how small chemical networks that make use of enzymatic chemical reactions on the colloid surface can be used to construct motor‐based chemical logic gates. The basic features of coupled enzymatic reactions that are responsible for propulsion and underlie the construction and function of chemical gates are described using continuum theory and molecular simulation. Examples are given that show how colloids with specific chemical logic gates, can perform simple sensing tasks. Due to the diverse functions of different enzyme gates, operating alone or in circuits, the work presented here supports the suggestion that synthetic motors using such gates could be designed to operate in an autonomous way in order to complete complicated tasks. [ABSTRACT FROM AUTHOR]

Heteroatom doping can tune the band structure of semiconductors and enhance their carrier transfer capacity for improving the performance of photoelectrochemical water oxidation. Nevertheless, the introduction of dopants is not always beneficial. In this study, magnesium (Mg) is adopted to dope ZnIn2S4 nanosheet array photoanodes to form a type‐II band structure and reduce bulk recombination, but concurrently introduced deleterious oxygen (O) defects slow down the surface catalytic reaction kinetics. Furthermore, a facile heat treatment strategy is proposed to transform these O defects into Mg─O bonds. First‐principles calculations and electrochemical characterization indicate that the presence of Mg─O bonds provides abundant active sites and efficiently accelerates the surface oxygen evolution reaction by precisely realigning the rate‐determining step from OH* to O* (step 2) to OOH* to O2 (step 4), thereby retarding charge trapping and recombination. As a result, such a photoanode achieves a remarkable performance with a photocurrent as high as 4.91 mA cm−2 at 1.23 V versus reversible hydrogen electrode, and the onset potential shifts negatively about 340 mV. This work provides a new defect modulation idea for converting detrimental defects to favorable ones, and it can be expected to have wide applications in the fields of energy, catalysis, and optoelectronics, etc. [ABSTRACT FROM AUTHOR]

Bimetallic catalysts combining precious and earth-abundant metals in well designed nanoparticle architectures can enable cost efficient and stable heterogeneous catalysis. Here, we present an interaction-driven in-situ approach to engineer finely dispersed Ni decorated Pt nanoparticles (1-6 nm) on perovskite nanofibres via reduction at high temperatures (600-800 oC). Deposition of Pt (0.5 wt%) enhances the reducibility of the perovskite support and promotes the nucleation of Ni cations via metal-support interaction, thereafter the Ni species react with Pt forming alloy nanoparticles, with the combined processes yielding smaller nanoparticles that either of the contributing processes. Tuneable uniform Pt-Ni nanoparticles are produced on the perovskite surface, yielding reactivity and stability surpassing 1 wt.% Pt/γ-Al2O3 catalysts for CO oxidation. This approach heralds the possibility of in-situ fabrication of supported bimetallic nanoparticles with engineered compositional distributions and performance. Utilizing "Chemistry at a point", Ni is exsolved from a perovskite lattice under deposited Pt nanoparticles. This yields even smaller Ni Pt alloy nanoparticles on a perovskite nanofiber structure, exhibiting high catalytic activity. [ABSTRACT FROM AUTHOR]

The possibilities of obtaining aluminum matrix composite materials of the composition Al–Al2O3 are considered by the method of liquid-phase oxidation of aluminum by purging the melt with oxygen. The obtained materials are a two-phase system with different concentrations of the solid phase. An algorithm for calculating the kinetics of aluminum oxidation in obtaining the oxide phase of an aluminum matrix composite is proposed. It is established that the beginning and completeness of the reaction on the surface of the gas bubble determines the synthesis of the oxide phase and is determined by the functions T(t), h(t) in the region of dynamic time delay, which, in turn, the queue is revealed as a function of the temperature in the contact zone of the gas bubble with the melt, taking into account the duration of the heating of the bubble along the cross section and the radius of the bubble itself. The microstructures of the obtained materials with different structural-phase state with variations in the time of purging and oxygen supply to the aluminum melt are presented. [ABSTRACT FROM AUTHOR]