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• Ni 3 In catalyst exhibits an increased formation barrier and lower adsorption strength for C* species. • The coverage of C* species is significantly lower on Ni 3 In than Ni catalysts. • There are more pathways to oxidize carbon-containing species on Ni 3 In catalyst. Dry methane reforming (DMR) reaction has garnered significant attention for its potential in consuming CO 2 for environmental sustainability, as well as utilizing CH 4 as a fossil resource with the highest hydrogen content. In-depth understanding the reaction mechanism with microkinetic modeling is essential for suppressing coke deposition and improving the stability of Ni catalysts. This study investigates the reaction intermediates and pathways of DMR on Ni 3 In alloy, which has been previously identified by theoretical high-throughput screening and experimental results as having improved resistance to carbon accumulation. Energetic profiles, determined through density functional theory calculations, reveal that the Ni 3 In catalyst exhibits an increased formation barrier for C* and lower adsorption strength compared to pure Ni catalyst. Microkinetic analysis using the CatMAP package demonstrates significantly lower carbon coverage on Ni 3 In than Ni catalysts. Importantly, the dissociation of CO 2 plays a critical role in influencing the rate of CO formation, particularly at higher reaction temperatures. Furthermore, through flux analysis, we have identified the main reaction pathways for CO formation and highlighted the multiple pathways for oxidizing carbon-containing species to suppress carbon deposition on Ni 3 In catalyst. These findings not only provide theoretical support for the experimental stability of Ni-In catalysts but also offer valuable insights for the rational design of other Ni-based bimetallic catalysts employed in DMR reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photocatalytic performance of plasma-treated Au catalyst depends on oxide supports. • Plasma-treatment leads to distinct interactions between oxide supports and Au. • Strong interaction between CeO 2 and Au enables high intrinsic activity of Au/CeO 2. • Moderate interaction between TiO 2 and Au favors forming Au-TiO 2 interfacial sites. • Au-TiO 2 interface exhibits low Schottky barrier height for hot-electron transfer. Supported Au nanocatalysts are highly attractive plasmonic nanostructures for visible light (VL) photocatalysis due to their significant promise in direct conversion of solar to chemical energy. A promising strategy to prepare high-performance supported plasmonic Au nanocatalysts is treating the catalysts with plasma, where the support holds the key to constructing active Au-support interfaces by interacting with Au nanoparticles. Herein the role of oxide supports in constructing plasma-treated plasmonic Au nanocatalysts for VL photocatalytic oxidation of CO is studied by comparing effect of plasma treatment on typical oxides of TiO 2 , CeO 2 and Al 2 O 3 supported Au nanocatalysts. After O 2 plasma treatment, CeO 2 supported Au nanocatalyst obtains the highest intrinsic catalytic activity due to its high dispersion of Au nanoparticles induced by strong interaction between CeO 2 and Au and strong oxygen activation ability. The O 2 plasma treatment enables TiO 2 supported Au nanocatalyst to exhibit the largest enhancement in catalytic activity under VL irradiation, which originates from the favorable hot-electron transfer process. This process is not only attributed to the strong surface plasmon resonance of Au nanoparticles and large numbers of Au-TiO 2 interfacial sites that result from moderate interaction between TiO 2 and Au, but also depends on the low Schottky barrier height at Au-TiO 2 interface due to the small work function difference between TiO 2 and metallic Au. This investigation deepens the understanding of the role of oxide supports in constructing plasma-treated supported Au nanocatalysts, and can be instructive for the design and optimization of plasmonic Au nanocatalysts for VL photocatalytic reactions. [ABSTRACT FROM AUTHOR]

• Light-irradiation converted type-Ⅱ CoPc/BiOBr to S-scheme heterostructure. • Co2+ of CoPc accumulated electrons and acted as active sites to reduce CO 2 to CO. • S-scheme CoPc/BiOBr boosted CO generation with a rate of 59.9 μmol g−1 h−1. With efficient charge separation, S-scheme heterostructures are very attractive for photocatalytic carbon dioxide reduction, but their construction is still facing challenge. Herein, cobalt phthalocyanine (CoPc) was combined with BiOBr nanosheets (NSs) as type-II heterostructure CoPc/BiOBr-NSs. It is more interesting that light-induced oxygen vacancies on BiOBr-NSs can convert type-II CoPc/BiOBr-NSs to S-scheme structures for CO 2 reduction. The optimal CoPc/BiOBr-NSs exhibited significantly enhanced CO generation with rate of 59.9 μmol g−1 h−1 (selectivity of 90.4 %), which was 25-fold higher than that of BiOBr-NSs, and much higher than most reported photocatalysts. Photo-induced oxygen vacancies on BiOBr-NSs can generate defect states on bottom of conduction band (CB), which can trap the electrons to have a recombination with holes left on HOMO band of CoPc, boosting charge separation for efficient CO 2 reduction. Moreover, the central Co2+ of CoPc can accept the excited electrons from the ligand to act as active site for CO 2 reduction. This work provides a new strategy of constructing metal-complex/semiconductor S-scheme photocatalyst for boosting CO 2 photoreduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • MSNS with center-radial mesopores shows shorter pore length than SBA-15. • Shorter pore length enhances performance of Ag/MSNS catalyst for DMO hydrogenation. • Differently sized MSNS with distinct pore lengths are fabricated for Ag catalyst. • Relationship between performance and diffusion is established for Ag/MSNS catalyst. Precisely regulating mesopore structures toward enhanced diffusion of reactants and targeted product is of great significance for achieving simultaneously improved activity and selectivity, which is exemplified by this work employing mesoporous silica with distinct structured mesopores as support for Ag catalysts to selectively hydrogenate dimethyl oxalate (DMO) into methyl glycolate (MG). Mesoporous silica nanosphere (MSNS) with center-radial pores shows shorter pore length than SBA-15 with parallel mesopores, which is beneficial for the diffusion process and thus gives rise to enhanced hydrogenation activity. Inspired by these insights, MSNSs sized in 50, 90, 120 and 160 nm are further synthesized to regulate pore length and systematically explore their effects on the reaction. The diffusion process is enhanced with decreasing the size of MSNS from 160 to 50 nm, as elucidated by the effective diffusion time constant (D e /R2) determined by zero-length column (ZLC) method. Accordingly, DMO can facilely diffuse into the mesopores with shorter length to access the active sites while the formed MG product can easily diffuse out to avoid the over-hydrogenation process, which is corroborated by the comparison for performances of these Ag/MSNSs catalysts. Notably, a moderately short pore length, balancing well the diffusion and hydrogenation process, is more preferable for achieving both higher activity and better selectivity to MG, and MSNS sized in 90 nm supported Ag catalyst thus exhibits the greatest performances, with MG selectivity up to 96.6 % at 99.7 % of DMO conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel C/N co-doped bilayer hollow structured MoSe 2 nanosheets are fabricated. • The hierarchical BH-MoSe 2 @CNBs are beneficial to improving the Na+ kinetics. • The BH-MoSe 2 @CNBs exhibit superior rate and cycling performance for half/full SIBs batteries. • The short and multichannel ion/electron transportation of BH-MoSe 2 @CNBs are responsible for boosted kinetics. It is of great significance to design and prepare high performance anode materials for the development of sodium ion batteries (SIBs). In this work, the innovative approach of interface and electronic structure dual-engineering is applied on MoSe 2 to fabricate novel C/N co-doped bilayer hollow structured MoSe 2 nanosheets (BH-MoSe 2 @CNBs). With the comparison of traditional MoSe 2 /C composite, the sandwich structured MoSe 2 with double carbon coating can bring multi-ion/electron transportation channels, favoring the Na+ storage and charge transfer kinetics. Specifically, the inner carbon shell as a supporting skeleton not only restrains the agglomeration of lamellar MoSe 2 , but also buffers the stress of sodium ions (de)insertion. The outer carbon layer plays a crucial role in adsorbing the polyselenide intermediates, maintaining the stability and reversible capacity of the middle MoSe 2 electrode. As anode for SIBs, BH-MoSe 2 @CNBs exhibit 347 mAh g−1 at 10 A g−1 after 1300 cycles, which is comparable with the previously reported MoSe 2 -based electrode in SIBs. Additionally, the BH-MoSe 2 @CNBs//Na 3 V 2 (PO 4) 2 O 2 F full cell can reach an energy density of 107.4 Wh kg−1 at a power density of 3832 W kg−1, indicating the potential practical application. The theoretical calculation is also conducted to confirm the superior Na+ adsorption of BH-MoSe 2 @CNBs. The interface and electronic structure dual-engineering on MoSe 2 can provide innovative points for the exploitation of efficient anode materials for SIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Substitution of transition metals for Cr increases the acidity of the adjacent O. • Linear scaling relations are established to identify the PDH activity descriptor. • High propylene selectivity of the M 1 -Cr 2 O 3 catalysts is achieved. • Cu 1 -Cr 2 O 3 is predicted to be the best catalyst for PDH among the 13 doped Cr 2 O 3. The catalytic behavior of M 1 -Cr 2 O 3 (M = Mn-Cu, Ru-Ag, and Os-Au) in propane dehydrogenation (PDH) has been studied by employing microkinetic modeling combined with results from periodic DFT + U calculations. Calculated results indicate that most of the single atoms concerned can be stably present on the Cr 2 O 3 surface. The adsorption energy calculations and Bader charge analysis demonstrate that the acidity of the O sites adjacent to the M sites would be enhanced upon doping, which in turn strengthens the atomic H adsorption and the co-adsorption of various PDH species. The surface H formation energy is identified as the reactivity descriptor for PDH over the M 1 -Cr 2 O 3 catalysts, and a volcano curve of the PDH activity is obtained. By calculating the difference between the propylene dehydrogenation and desorption barriers, it is found that some M 1 -Cr 2 O 3 catalysts show improved selectivity towards propylene, as compared to Cr 2 O 3. Comparison between the formation barriers of H 2 and H 2 O reveals that single-atom doping has no apparent negative effect on the catalytic stability of the Cr 2 O 3 surface. The Cu 1 -Cr 2 O 3 catalyst is finally identified as the most promising catalyst for PDH among the 13 M 1 -Cr 2 O 3 catalyst candidates, considering the catalytic activity, selectivity, stability, and cost. [ABSTRACT FROM AUTHOR]

[Display omitted] • A scaling relation-based L-H kinetic model is proposed to assess reaction rate. • Principles for making a kinetically consistent free energy profile are suggested. • Surface site coverages is estimated from free energy diagram of intermediates. • Reaction rate is straightforwardly obtained from the free energy diagram of reaction. • The model predicted resutls fit microkinetic modeling well for three model reactions. We report a scaling relation-based L-H kinetic model to assess reaction rate, where general principles for making a kinetically consistent free energy profile are suggested. Water-gas shift, Fischer-Tropsch synthesis, and steam methane reforming are employed as three model reactions to illustrate this approach. Herein, potential energies and free energies are calculated by improved scaling relations. The different methods to construct energy profiles are compared, and free energy diagrams rather than potential energy diagrams are more favorable to be employed in the field of reaction mechanism discriminations and kinetics investigations due to consisting of thermodynamic information. The sequence of various elementary steps is important to generate appropriate rate-determining step and rate expressions. It is suggested that the sequence of the elementary step follows a principle that the reaction step is set just before it is required, and desorption occurs just after the formation of the intermediates. Based on the procedure elucidated here, it is easy to get turnover frequency straightforwardly from the free energy diagram of reaction and the surface site coverages from the free energy diagram of intermediates. The scaling relation-based L-H kinetic model exhibits a similar accuracy for predicting the surface coverages and reaction rates with full microkinetic modeling toward all the three model reactions. It demonstrates that the approach proposed herein greatly simplifies the calculation but maintains high accuracy as compared to full microkinetic modeling. This approach can be widely applied for kinetic modeling to elucidate the reaction mechanism and kinetics for chemical processes of interest. [ABSTRACT FROM AUTHOR]