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The photothermocatalytic cellulose steam reforming strategy has provided a sustainable approach, directly converting the largest renewable carbon resource (biomass), into syngas (H2 and CO) which are clean and high‐value‐added energy carriers. However, this strategy for achieving high catalytic efficiency inevitably produces char, resulting in rapid deactivation and difficult recovery of catalysts, impeding industrial application. Herein, the Ni NPs (nanoparticles) loaded on θ‐phase Al2O3 (Ni/θ‐Al2O3) catalyst enable efficient conversion of char generated during photothermocatalytic cellulose steam reforming process, thereby exhibiting high production rates of syngas (H2 3776.3 and CO 2028.1 mmol gcatalyst−1$ \rm{g}_{catalyst}^{-1} $ h−1) and excellent durability (no deactivation after 4 cycles). Compared with a reference catalyst of Ni NPs loaded on amorphous SiO2 (Ni/am‐SiO2), this study finds that the elementary step of char conversion with H2O to syngas can be enhanced on Ni/θ‐Al2O3. With an emphasis on the mechanism, a different pathway is discovered that surface hydroxyl groups participating in the formation of HCO* intermediates, further dissociating to syngas, significantly facilitate the conversion of char. Additionally, on Ni/θ‐Al2O3, the photoactivation effect enhances catalytic activity, particularly promoting the conversion of H2O with char to syngas, thus preventing deactivation caused by encapsulation of char. [ABSTRACT FROM AUTHOR]

The photothermocatalytic cellulose steam reforming strategy has provided a sustainable approach, directly converting the largest renewable carbon resource (biomass), into syngas (H2 and CO) which are clean and high‐value‐added energy carriers. However, this strategy for achieving high catalytic efficiency inevitably produces char, resulting in rapid deactivation and difficult recovery of catalysts, impeding industrial application. Herein, the Ni NPs (nanoparticles) loaded on θ‐phase Al2O3 (Ni/θ‐Al2O3) catalyst enable efficient conversion of char generated during photothermocatalytic cellulose steam reforming process, thereby exhibiting high production rates of syngas (H2 3776.3 and CO 2028.1 mmol gcatalyst−1$ \rm{g}_{catalyst}^{-1} $ h−1) and excellent durability (no deactivation after 4 cycles). Compared with a reference catalyst of Ni NPs loaded on amorphous SiO2 (Ni/am‐SiO2), this study finds that the elementary step of char conversion with H2O to syngas can be enhanced on Ni/θ‐Al2O3. With an emphasis on the mechanism, a different pathway is discovered that surface hydroxyl groups participating in the formation of HCO* intermediates, further dissociating to syngas, significantly facilitate the conversion of char. Additionally, on Ni/θ‐Al2O3, the photoactivation effect enhances catalytic activity, particularly promoting the conversion of H2O with char to syngas, thus preventing deactivation caused by encapsulation of char. [ABSTRACT FROM AUTHOR]

The high selectivity of C─C coupling reactions in Fischer–Tropsch synthesis (FTS) is often limited due to the difficulty in the regulation of transition metals acting as active sites to balance between C─C chain propagation and over hydrogenation. Herein, BCN‐supported CoFe alloy catalyst has been successfully constructed for promoting C─C chain propagation. When exposed to light irradiation, the CoFe‐BCN catalyst exhibits a higher CO conversion of 18.4% with the enhanced selectivity toward multi‐carbon (C2+) hydrocarbons that increases from 22.4% to 64.1%, and the reduced over hydrogenation to CH4 that decreases from 74.8% to 25.4% in contrast to Co‐BCN catalyst. Structural characterizations indicate that introducing Fe to create CoFe alloy can decrease the d‐band center of Co, which significantly promotes C─C coupling reactions but weakens hydrogenation in FTS process. The findings underscore the potential of modifying catalysts with metal atoms to optimize their electronic structure to regulate reaction pathways in CO hydrogenation for high‐value products formation. [ABSTRACT FROM AUTHOR]

Although there are many promising works in the field of Fischer–Tropsch synthesis (FTS), it is still a huge challenge to achieve the rational design of FTS catalysts for excellent selectivity toward light olefins with a high olefins/paraffins ratio (o/p ratio). Herein, a hydrophobic core–shell Fe‐based FTS catalyst is developed by calcination and hydrophobic modification of polyvinylpyrrolidone (PVP)‐decorated Prussian blue (PB, Fe4[Fe(CN)6]3) precursor. The hydrophobic modification is achieved by using trimethylchlorosilane (TMCS) as the hydrophobic agent. Under light irradiation and near ambient pressure (0.18 MPa), compared with the catalyst without the hydrophobic surface to mainly convert CO to valueless CO2, the optimal catalyst delivers excellent selectivity of 48.0% for value‐added light olefins (C2–4=) with a high o/p ratio of 10.1 but low selectivity for CO2 at a CO conversion of 22.6%. The excellent FTS performance can be attributed to that the hydrophobic surface of the catalyst regulates the chemical reaction pathway, which promotes the CO hydrogenation but suppresses the conversion of CO to CO2. The study demonstrates that a rationally designed functional surface of a catalyst can govern the reaction pathway along value‐added solar‐to‐chemicals conversion. [ABSTRACT FROM AUTHOR]

Solar‐driven CO2 hydrogenation into multi‐carbon products is a highly desirable, but challenging reaction. The bottleneck of this reaction lies in the C−C coupling of C1 intermediates. Herein, we construct the C−C coupling centre for C1 intermediates via the in situ formation of Co0−Coδ+ interface double sites on MgAl2O4 (Co−CoOx/MAO). Our experimental and theoretical prediction results confirmed the effective adsorption and activation of CO2 by the Co0 site to produce C1 intermediates, while the introduction of the electron‐deficient state of Coδ+ can effectively reduce the energy barrier of the key CHCH* intermediates. Consequently, Co−CoOx/MAO exhibited a high C2–4 hydrocarbons production rate of 1303 μmol g−1 h−1; the total organic carbon selectivity of C2–4 hydrocarbons is 62.5 % under light irradiation with a high ratio (≈11) of olefin to paraffin. This study provides a new approach toward the design of photocatalysts used for CO2 conversion into C2+ products. [ABSTRACT FROM AUTHOR]

It is very essential to improve the activity and selectivity of photothermocatalysis (PTC) by tailoring the microstructures of photothermocatalytic materials. Herein, we exploit a facet‐heterojunction strategy to fabricate photothermocatalysts, by which CdS−Au‐{001}BiOCl{110}‐MnOx is constructed by respectively depositing CdS−Au on the {001} facets and MnOx on {110} facets of BiOCl nanosheets. This material exhibits excellent activity for toluene oxidation and near 100 % selectivity from toluene to carbon dioxide under full‐spectrum sunlight irradiation. The conversion rate of toluene under PTC condition is significantly enhanced by 47.5, 1.8 and 1.7 times compared with that of sole PC, TC and the sum of TC and PC. There is a synergistic effect between photocatalysis and thermocatalysis, in which the S‐scheme photocatalyst CdS−Au‐{001}BiOCl produces high‐energy active species to activate toluene and accelerate the cycle conversion of lattice oxygen and oxygen vacancy in MnOx. [ABSTRACT FROM AUTHOR]

The photoreduction of CO2 is attractive for the production of renewable fuels and the mitigation of global warming. Herein, we report an efficient method for CO2 reduction over elemental boron catalysts in the presence of only water and light irradiation through a photothermocatalytic process. Owing to its high solar-light absorption and effective photothermal conversion, the illuminated boron catalyst experiences remarkable self-heating. This process favors CO2 activation and also induces localized boron hydrolysis to in situ produce H2 as an active proton source and electron donor for CO2 reduction as well as boron oxides as promoters of CO2 adsorption. These synergistic effects, in combination with the unique catalytic properties of boron, are proposed to account for the efficiency of the CO2 reduction. This study highlights the promise of photothermocatalytic strategies for CO2 conversion and also opens new avenues towards the development of related solar-energy utilization schemes. [ABSTRACT FROM AUTHOR]

The photoreduction of carbon dioxide to give value‐added products is attractive for the production of renewable fuels and the mitigation of global warming. In their Communication on page 5570 ff., J. Ye et al. report an efficient method for CO2 reduction over elemental boron in the presence of only water and under light irradiation through a one‐step photothermocatalytic process. The boron material harvests the incident light, converts it into thermal energy, generates hydrogen, and catalyzes the overall process. [ABSTRACT FROM AUTHOR]