Versatile Microreactor for Solar-Driven Photothermal Catalytic CO₂ Reduction into Fuels

The efficiency of solar-driven photocatalytic CO2 reduction is not solely upon the catalyst; the reactor design also exerts a profound influence. Solar energy capture, reaction interface construction, and reaction condition regulation constitute a particular challenge in the practical experiment of photocatalytic CO2 reduction. A versatile microreactor was elaborately developed to address these challenges by combining the assembly of a novel reaction structure and the configuration of whole-process regulation modules, which can be applied to both particle-suspension and fixed-bed reactions. The solar capture, reactant supply, and triphase interface in CO2 reduction are harmoniously integrated. The light transmittance was improved by applying a hydrophilic coating to defog the reactor cover plate, the reactant transport was optimized by constructing the triphase structure, the energy and species were enriched in the porous catalyst layer prepared by electrospinning technology, and the standardization of the reaction was realized by in situ monitoring of parameters. A comprehensive CO2 reduction test and characterization were conducted with a common catalyst in different reaction modes, which verified the feasibility and superiority of the reactor, and demonstrated that the reactor can serve as a general experimental platform for CO2 reduction with multiple functions to evaluate the activity of various catalytic materials and study the mechanism of reaction conditions.