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The achievement of excellent catalytic activity for electricity‐driven CO2 reduction over a wide potential window is significant for the mature applications. However, the efficient potential range is always limited by the dilemma in CO2 activation and product desorption at different potentials, due to the scaling relationships of adsorption energy. Herein, we developed a nanostructured Ag‐CO3 electrocatalyst featuring metallic Ag with Ag(220) orientation on the surface and Ag2CO3 beneath. The interactions between Ag and Ag2CO3 lead to lattice expansion on the surface of Ag, resulting in electron localization and accordingly enhanced CO2 activation to *COOH on Ag. Furthermore, this lattice expansion induces a change in the *CO adsorption geometry from a bridge mode to a linear mode, which compensates the promotion effect of electron localization on *CO adsorption energy. As a result, the scaling relationship between *COOH and *CO adsorption energy was disrupted, leading to enhanced *COOH adsorption and inferior *CO adsorption. Consequently, the Ag‐CO3 catalyst exhibited a high FECO (>80%) over a robust potential window of −0.8 to −1.8 V (vs. RHE), with a maximum FECO of 95% at −1.2 V (vs. RHE). The mechanism described herein offers a universal design principle for the development of high‐efficiency CO2 electroreduction catalysts that operate effectively within a broad potential range. [ABSTRACT FROM AUTHOR]

Direct synthesis of 2,1-benzisoxazole and its related N-heterocyclic compounds via a chemoselective reductive heterocyclization route, which involves hydrogenation and subsequent intramolecular cyclodehydration steps, is a viable and attractive approach. However, the efficient transformation of the feedstocks using hydrogen as a hydrogen source at ambient temperature and atmospheric hydrogen pressure remains a great challenge. Herein, we reported a MgO-incorporated porous carbon composite (MgO@C) stabilized subnanometric Pt cluster (Pt/MgO@C) catalyst prepared by annealing a Mg-containing metal–organic framework, Mg-MOF-74, followed by impregnation of a Pt precursor and further reduction treatment strategy. The as-prepared Pt/MgO@C with ultralow Pt loading (0.078 wt%) exhibited superior catalytic performance for synthesizing 2,1-benzisoxazole derivatives by the reductive heterocyclization methodology. Excellent catalytic activity (conversion ≥ 99%), high chemoselectivity (≥92%), good stability (8 cycles), and broad functional group tolerance (10 substrates) were achieved under very mild conditions (1 bar hydrogen pressure at 303 K) over the developed Pt/MgO@C. Control experiments indicated that a proper amount of basic sites, subnanometric Pt clusters, and a close contact between them synergistically contributed to the extraordinary performance of Pt/MgO@C. Density functional theory calculations showed that the high activity and chemoselectivity of Pt/MgO@C stemmed from the active interfacial sites of Pt/MgO@C simultaneously activating the H2 and substrate, where the formed stable hydroxyl groups contributed to the enhancement of activity. The combined experimental and theoretical approach identified the formation of the –NO and –NHOH groups during the hydrogenation process, and the former corresponds to the rate-determining step. [ABSTRACT FROM AUTHOR]

Rational screening of efficient supported metal catalysts is still a great challenge due to the complicated reaction mechanism for selective polyol oxidation. Exemplifying glycerol oxidation to glyceric acid as a model reaction, we perform a DFT assisted descriptor based microkinetic modeling to reveal the underlying mechanism. It is found that the addition/formation of OH− could polarize the metal surface (M‐OH*) to regulate the d‐band center of Pt accompanied by the electron transfer from OH− to metal atoms, thus promoting the adsorption of glycerol. Moreover, the linear chemisorption energy and transition state energy scaling relations are well established on the formation energies of adsorbed C and O. Activity map obtained from descriptor based microkinetic analysis demonstrates that Pt and Ir metals exhibit the highest catalytic activity. Meanwhile, further analysis of the desorption energy and CC bond cleavage activation energy of glyceric acid product shows that Au and Pt metals display the optimal glyceric acid selectivity. Satisfactorily, these results from microkinetic analysis are in good agreement with the comparative experimental results. The insights revealed here may open a new avenue for rational design of transition metal catalysts in the bio‐polyol oxidation system. [ABSTRACT FROM AUTHOR]

Simultaneous transformation of CO2 and H2O into syngas (CO and H2) using solar power is desirable for industrial applications. Herein, an efficient photocatalyst based on double‐shelled nanoboxes, with an outer shell of hydroxy‐rich nickel cobaltite nanosheets and an inner shell of Cu2S (Cu2S@ROH‐NiCo2O3), is prepared via a multistep templating strategy. The high performance of Cu2S@ROH‐NiCo2O3 (7.1 mmol g−1 h−1 for CO; 2.8 mmol g−1 h−1 for H2) is attributed to the hierarchical hollow geometry and p–n heterojunction to promote light absorption and charge separation. Spectroscopic and theoretical analyses elucidate that the ROH‐NiCo2O3 surface enhances *CO2 adsorption and lowers energy barriers for CO2‐to‐CO. Therefore, modulating the hydroxy contents of ROH‐NiCo2O3 can achieve broad CO/H2 ratios from 0.51 to 1.24. This work offers in‐depth insights into adjustable syngas photosynthesis and generalized concepts of selective heterogeneous CO2 photoreduction beyond cobalt‐based oxides. [ABSTRACT FROM AUTHOR]

Aqueous phase reforming (APR) of ethylene glycol was performed at 225 °C and 30 bar in batch and continuous reaction conditions. The effect on the APR performance by functionalizing carbon supports with nitrogen and adding Mn to Pt-based catalysts was investigated. The presence of nitrogen species on the carbon surface and Mn-addition (PtMn) improved the catalytic activity and promoted H 2 production. XPS results suggest that the enhancement of the catalytic activity may be attributed to charge transfer from platinum to the nitrogen groups and Mn. Pt-based catalysts were stable under the studied reaction conditions, while up to 97 % of the manganese leached into the liquid solution during APR. However, the catalytic activity was maintained even with such significant decrease in Mn content, indicating that only a small amount of Mn is necessary to maintain the promotional effect on Pt during APR. [Display omitted] • Electronic interactions between Pt-N and Pt-Mn led to enhanced catalytic activity. • N-doped carbon nanofibers effectively improved H 2 yield in aqueous phase reforming. • Pt-based catalyst promoted with Mn presented higher H 2 yield and selectivity. • Metal-support interactions are key factors in promoting catalytic activity. [ABSTRACT FROM AUTHOR]

• Microkinetic analysis is used to screen perovskites for methane partial oxidation. • The catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3. • Bulk oxygen vacancy formation energy is identified as a single descriptor. • 667 combinations of A- and B-cations have been screened in terms of stability. • SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are identified as catalyst candidates. DFT calculations and descriptor-based microkinetic analysis have been performed to screen ABO 3 perovskite catalysts for methane partial oxidation. The scaling relations indicate the adsorption energies of H@O and CH 3 @B have the capability of representing the energetics of methane oxidation, and bulk oxygen vacancy formation energy is identified to be a better single descriptor of the kinetics. The resultant volcano-shaped plot shows the catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3 , which agrees with the experimental findings and thus validates our theoretical predications. By screening 667 combinations of A- and B-cations based on electron neutrality, structural tolerance factors, and experimental verification, 77 ABO 3 have been identified to be stable. Of them, SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are located at the summit of the volcano, which also exhibit satisfactory CO selectivity and enhanced carbon resistance compared to LaFeO 3 , and may act as the oxygen carrier candidates. [ABSTRACT FROM AUTHOR]

• A series of Zn SACs synthesized via a ZIF-8-mediated sacrificial template strategy. • Zn–N–C–T exhibited high performance in transfer hydrogenation nitrobenzene to aniline. • The activity of Zn–N–C–T is closely related to the coordination number of Zn sites. • The hydrogenation mechanism over Zn–N–C–1223 is disclosed by the DFT calculations. Metal single-atom catalysts (SACs) have great potential to replace traditional nanoparticle catalysts in practical applications, however, the task-specific construction of SACs containing metal–nitrogen (M−N) moiety with tunable M−N coordination number remains a colossal challenging issue. Herein, we report a facile strategy to modulate the s-band of Zn by constructing N-coordinated Zn SACs (denoted as Zn–N–C–T, T stands for the pyrolysis temperature) with tunable nitrogen coordination number (denoted as Zn–N x , x = 2, 3, and 4) and Zn loadings (ranging from 0.8 to 6.8% by weight) via a metal–organic framework-mediated pyrolysis method. The catalytic activity of Zn–N–C–T is found to be closely related to the coordination number of Zn single atomic sites for the transfer hydrogenation of nitroarene to arylamine, using hydrazine hydrate as a hydrogen source under environmental benign conditions, among which the under-coordinated Zn–N 3 with defect and asymmetric electron distribution in Zn–N–C–1223 exhibits the best catalytic activity, followed by lower-coordinated Zn–N 2 with defect in Zn–N–C–1273 and saturated coordination Zn–N 4 in Zn–N–C–1123. Experimental results and theoretical analysis uncover that appropriately lowering the coordination number increases the electron density of Zn single atoms and simultaneously introduces H-acceptor sites, which cooperatively contribute to the enhancement of the performance for transfer hydrogenation. [ABSTRACT FROM AUTHOR]

In order to improve the degradation activity of β-glucosidase (CpBgl) from Coniophora puteana , the structural modification was conducted. The enzyme activity of mutants CpBgl-Q20C and CpBgl-A240S was increased by 65.75% and 58.58%, respectively. These mutants exhibited maximum activity under the same conditions as wild-type CpBgl (65 ℃ and pH 5.0), slightly improved stabilities compared that of the wild-type, and remarkably enhanced activities in the presence of Mn2+ or Fe2+. The V max of CpBgl-Q20C and CpBgl-A240S was increased to 138.18 and 125.14 μmol/mg/min, respectively, from 81.34 μmol/mg/min of the wild-type, and the catalysis efficiency (k cat / K m) of CpBgl-Q20C (335.79 min−1/mM) and CpBgl-A240S (281.51 min−1/mM) was significantly improved compared with that of the wild-type (149.12 min−1/mM). When the mutant CpBgl-Q20C were used in the practical degradation of different biomasses, the glucose yields of filter paper, corncob residue, and fungi mycelia residue were increased by 17.68%, 25.10%, and 20.37%, respectively. The spatial locations of the mutation residues in the architecture of CpBgl and their unique roles in the enzyme-substrate binding and catalytic efficiency were probed in this work. These results laid a foundation for evolution of other glycoside hydrolases and the industrial bio-degradation of cellulosic biomass in nature. [Display omitted] • Improved β-glucosidase mutants were obtained via site-directed mutagenesis. • The activity of CpBgl-Q20C and CpBgl-A240S was increased by 65.75% and 58.58%. • The molecular mechanism of improved activity was preliminarily elucidated. • CpBgl-Q20C and CpBgl-A240S effectively promoted biomass cellulose degradation. [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]

In order to improve the catalytic efficiency of cellulase for more effective utilization of lignocellulose, a novel endoglucanase (CgEndo) from Colletotrichum graminicola was expressed by Pichia pastoris X33 and modified by site-directed mutagenesis. Two mutants, Y63S and N20D/S113T, with 62.31% and 57.14% increased enzyme activities were obtained, respectively. On this basis, their biochemical properties, kinetic parameters, structural information as well as the application in biomass degradation were investigated and compared with the wild-type CgEngo. The results indicated that the mutation Y63S and N20D/S113T resulted in an improvement of proximity between enzyme and substrate through conformational changes of the catalytic region, which might contribute to the higher enzyme activities and catalysis efficiency (K cat / K m) of Y63S and N20D/S113T. These findings laid important foundation for the further engineering of this endoglucanase and practical application in efficient degradation of cellulosic biomass in nature. [Display omitted] • Improved endoglucanase CgEndo mutants were obtained via site-directed mutagenesis. • The activities of Y63S and N20D/S113T were 62.31% and 57.14% increased, respectively. • Y63S and N20D/S113T could effectively promote natural cellulose degradation. [ABSTRACT FROM AUTHOR]