Constructing Bi2MoO6/Pomelo-Peel-Derived Carbon 0D/3D Heterojunctions To Enhance Photothermal Catalytic CO2 Reduction in Full Solar Spectrum

The carrier migration limitation has been a key factor restricting the photothermal catalytic CO2 reduction. To further enhance carrier transport, Bi2MoO6 quantum dots (BM QDs) are deposited on the surface of alkali-activated pomelo-peel-derived carbon (CPP-A) to construct CPP-A/BM QDs 0D/3D heterojunctions in this paper. BM QDs have extremely short carrier transport distances and achieve photothermal synergy through the graded utilization of the full solar spectrum. The carbon framework of CPP promotes the high dispersion of BM QDs (3 nm) and allows the local surface temperature of the catalyst to increase rapidly up to 100 °C. The critical role of heat enhances the diffusion, adsorption, and carrier migration processes of CO2 and provides the energy to cross the CO2 activation energy barrier. More importantly, the oxygen-containing groups of CPP and BM QDs form a C–O–Bi interfacial electron bridge, which provides a high-speed channel for carrier transport across the interface, allowing many electrons generated by BM QDs to migrate rapidly to the CPP surface, inducing CPP as a new electron-rich surface for rapid CO2 activation, which results in an ultrahigh CO yield of 61.44 μmol/(g·h) for CPP-A/BM QDs, and the catalytic activity is increased by 9.12 times.