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Photothermal dry reforming of methane (DRM), as an emerging branch of heterogeneous catalysis, could effectively convert CO2and CH4into high-value-added chemicals viathe synergistic effect between thermochemical and photochemical processes. Herein, we report that loading Rh nanoparticles (NPs) on Ga2O3−xwith oxygen vacancies improves CO2conversion efficiency through photo-assisted DRM. On the Rh/Ga2O3−xcatalyst, the photothermal catalytic CO2conversion rate (112.0 μmol g−1min−1) is 1.6 times that of the thermal reaction at 500 °C (71.9 μmol g−1min−1). Rh2O3and Ga2O3as precursors are in situreduced to Rh NPs and Ga2O3−xunder the reductive DRM reaction atmosphere, respectively. Characterization results indicate that Rh NPs accelerate the DRM process by enhancing light absorption ability and charge transfer efficiency. Meanwhile, the oxygen vacancies in Ga2O3−xare beneficial for activating reactant molecules rapidly. In situDRIFTS spectra showed that Rh NPs and oxygen vacancies served as reduction and oxidation sites during the photothermal DRM process. This work paves the way for the rational design of better photothermal catalysts in the future.

Selectively removing the trace amount of ethyne in ethylene is of great significance for the utilization of ethylene in downstream processing. Selective hydrogenation of ethyne to ethylene is of great potential for large and medium-sized ethylene plants due to its advantages, such as low energy consumption, less environmental pollution, and large treatment capacity. In the reaction of selective hydrogenation of ethyne, catalysts play crucial roles in selectively driving the target reaction while suppressing the occurrence of side reactions. Up to now, a number of catalysts have been designed for selective hydrogenation of ethyne, which could roughly be divided into Pd-based catalysts, Ni-based catalysts, IB metal-based catalysts, bimetallic/trimetallic catalysts, and others, according to the nature of the active centers. Herein, the recent progress of these categories of catalysts in selective hydrogenation of ethyne is summarized and the underlying reaction mechanism is unraveled, targeting design of better catalysts for selective hydrogenation of ethyne and advancing this research field.

Photothermal synergistic CO2reforming of CH4(CRM) is a promising avenue to convert the greenhouse gases (CO2and CH4) into valuable chemicals and store the abundant clean solar energy into chemical energy simultaneously. Developing photothermal catalysts that could drive CRM efficiently at low temperatures remains as a challenge. In the present study, Nb2O5supported group VIII metal catalysts (M/Nb2O5) were synthesized, with the typical catalyst Rh/Nb2O5recording a CO2conversion rate of 50.6 mmol gRh−1min−1in CRM at 500 °C under visible light irradiation, about double fold higher than that achieved under the thermal-driven reaction condition. Mechanism study disclosed that oxygen vacancy was generated in situ over M/Nb2O5under the CRM reaction atmosphere. The oxygen vacancy promoted CO2adsorption and enhanced the light harvesting capacities of M/Nb2O5catalysts, which ultimately boosted their activities in photothermal CRM. This study provides a promising pathway for the rational design of efficient catalysts by tailoring the properties of the catalysts under the reaction atmosphere.