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Solar‐to‐chemical energy conversion under weak solar irradiation is generally difficult to meet the heat demand of CO2 reduction. Herein, a new concentrated solar‐driven photothermal system coupling a dual‐metal single‐atom catalyst (DSAC) with adjacent Ni−N4 and Fe−N4 pair sites is designed for boosting gas‐solid CO2 reduction with H2O under simulated solar irradiation, even under ambient sunlight. As expected, the (Ni, Fe)−N−C DSAC exhibits a superior photothermal catalytic performance for CO2 reduction to CO (86.16 μmol g−1 h−1), CH4 (135.35 μmol g−1 h−1) and CH3OH (59.81 μmol g−1 h−1), which are equivalent to 1.70‐fold, 1.27‐fold and 1.23‐fold higher than those of the Fe−N−C catalyst, respectively. Based on theoretical simulations, the Fermi level and d‐band center of Fe atom is efficiently regulated in non‐interacting Ni and Fe dual‐atom pair sites with electronic interaction through electron orbital hybridization on (Ni, Fe)−N−C DSAC. Crucially, the distance between adjacent Ni and Fe atoms of the Ni−N−N−Fe configuration means that the additional Ni atom as a new active site contributes to the main *COOH and *HCO3 dissociation to optimize the corresponding energy barriers in the reaction process, leading to specific dual reaction pathways (COOH and HCO3 pathways) for solar‐driven photothermal CO2 reduction to initial CO production. [ABSTRACT FROM AUTHOR]

In this reported work, lotus leaves‐derived biochar (LBC) was modified using various chemical methods. LBC prepared by different modification methods was used as the carrier for the development of low‐temperature selective catalytic reduction (SCR) catalysts. A comparative study of low‐temperature SCR manganese catalysts based on LBC chemically modified using NaOH, HNO3 and hexadecylcetyltrimethylammonium bromide (CTAB) was performed, revealing different deNOx performance of these catalysts. For the supported catalysts, the 25%Mn/LBC‐OH catalyst appeared to be optimum since it exhibited over 95% NOx conversion at 225 °C with a space velocity of 37 500 h−1. The microstructure, phase composition, redox properties and surface acidity were determined using field emission scanning electron microscopy, Brunauer–Emmett–Teller surface area, X‐ray diffraction, H2‐temperature‐programmed reduction, NH3‐temperature‐programmed desorption, and so forth. The results showed that the excellent SCR performance of 25%Mn/LBC‐OH was closely related to its abundant high valence Mn, suitable surface acidity and high redox capability. More importantly, highly dispersed MnOx easily formed on the surface of the LBC‐OH support, which was the key factor in the excellent catalytic activity of 25%Mn/LBC‐OH catalyst. Furthermore, the highly dispersed 25%Mn/LBC‐OH catalyst also exhibited improved tolerance to SO2 and H2O, making this catalyst a good candidate for reducing the NOx emission from coal‐fired power plants. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hierarchical Co3O4 nanocatalysts with different morphologies and various exposed crystal planes were synthesized via a hydrothermal process without the use of a cobalt surfactant precursor and subsequent direct thermal decomposition. The morphologies obtained include 3D hierarchical cube-stacked Co3O4 microspheres (C sample), 3D hierarchical plate-stacked Co3O4 flowers (P sample), 3D hierarchical needle-stacked Co3O4 double-spheres with an urchin-like structure (N sample), and 3D hierarchical sheet-stacked fan-shaped Co3O4 (S sample), which exhibit high efficiency for the total oxidation of volatile organic compounds (VOCs). Among them, the C sample exhibits the best activity with the temperature required for achieving a toluene conversion of 90% (T90%) of approximately 248 °C and the activity energy (Ea) of 80.2 kJ mol−1, which is at least 32 °C lower than that of the S sample with a higher Ea of 114.9 kJ mol−1 at a space velocity (WHSV) of 48 000 mL g−1 h−1. The effects of morphology on the physicochemical properties and catalytic activity of the Co3O4 catalysts are investigated using numerous analytical techniques. It is concluded that the large specific surface area, highly defective structure with abundant surface adsorbed oxygen species and rich high valence Co ions in the C sample are responsible for its excellent catalytic performance. Moreover, no significant decrease in catalytic efficiency is observed over 120 h at 255 °C on the C sample, which indicates that it exhibits excellent stability for toluene oxidation. Therefore, it shows potential as a non-noble catalyst in practical applications. [ABSTRACT FROM AUTHOR]

The present work elucidated the shape effect of Pt/CeO 2 catalysts toward catalytic oxidation of toluene. CeO 2 nanorods, nanoparticles, and nanocubes, dominantly exposed {1 1 0}, {1 1 1}, and {1 0 0} facet, respectively, were employed to immobilize Pt nanoparticles with tunable size by the adsorption method. The catalytic oxidation of toluene was evaluated. Their catalytic performance shows significantly support-shape-dependent behaviour, and the Pt/CeO 2 -r sample exhibits the best catalytic activity due to the best reducibility and highest concentration of surface oxygen vacancies. Furthermore, two types of TOFs based on the Pt dispersion and the concentration of surface oxygen vacancies were calculated, and the results suggest the oxygen vacancies on ceria surface control the reaction rate. In addition, in-situ UV Raman spectroscopy demonstrates that the supply of active oxygen controls the reaction rate and the surface oxygen vacancies play the role to replenish active oxygen species from gaseous phase and accelerate oxygen cycle for the toluene oxidation. [ABSTRACT FROM AUTHOR]

Strong metal-support interaction (SMSI), which has drawn widespread attention in heterogeneous catalysis, is thought to significantly affect the catalytic performance for volatile organic chemical (VOC) abatement. In the present study, strong interactions between platinum and ceria are constructed by modulating the oxygen vacancy concentration of CeO 2 through a NaBH 4 reduction method. For a catalyst with higher content of oxygen vacancy, more electrons would transfer from ceria to Pt, which is attributed to the stronger effect of SMSI. The obtained electron-richer Pt sites exhibit higher ability for toluene activation, contributing to better performance for toluene oxidation. On the other hand, the stronger metal-support interaction would facilitate CeOx species migrating to the Pt nanoparticle surface and forming an encapsulated structure. Smaller Pt dispersion leads to fewer sites for toluene adsorption and activation, which is to the disadvantage of the reaction. Therefore, taking the negative and positive effects together, the Pt/CeO 2 -0.5 catalyst has the highest catalytic performance for toluene abatement. Our study provides new insights into strong metal-support interaction on toluene oxidation and contributes to designing noble metal catalysts for VOC abatement.

Solar-to-chemical energy conversion under weak solar irradiation is generally difficult to meet the heat demand of CO 2 reduction. Herein, a new concentrated solar-driven photothermal system coupling a dual-metal single-atom catalyst (DSAC) with adjacent Ni-N 4 and Fe-N 4 pair sites is designed for boosting gas-solid CO 2 reduction with H 2 O under simulated solar irradiation, even under ambient sunlight. As expected, the (Ni, Fe)-N-C DSAC exhibits a superior photothermal catalytic performance for CO 2 reduction to CO (86.16 μmol g -1  h -1 ), CH 4 (135.35 μmol g -1  h -1 ) and CH 3 OH (59.81 μmol g -1  h -1 ), which are equivalent to 1.70-fold, 1.27-fold and 1.23-fold higher than those of the Fe-N-C catalyst, respectively. Based on theoretical simulations, the Fermi level and d-band center of Fe atom is efficiently regulated in non-interacting Ni and Fe dual-atom pair sites with electronic interaction through electron orbital hybridization on (Ni, Fe)-N-C DSAC. Crucially, the distance between adjacent Ni and Fe atoms of the Ni-N-N-Fe configuration means that the additional Ni atom as a new active site contributes to the main *COOH and *HCO 3 dissociation to optimize the corresponding energy barriers in the reaction process, leading to specific dual reaction pathways (COOH and HCO 3 pathways) for solar-driven photothermal CO 2 reduction to initial CO production., (© 2023 Wiley-VCH GmbH.)