Precisely constructed synergistic Dy–Co dual sites for promoting photoreduction CO2 in pure water

A B S T R A C T The key for photocatalytic CO 2 reduction in pure water lies in constructing active sites that possess both rapid charge transfer and efficient CO 2 adsorption. Here, atomically dysprosium (Dy)-cobalt (Co) dual sites anchored g-C 3 N 4 (CN) microtube were successfully fabricated by a precoordination-thermopolymerization strategy, in which Co 2+ and Dy 3+ ions are selectively coordinated with melamine and cyanuric acid, respectively, prior to thermal polymerization. The optimized Co 1 Dy 1 /CN catalyst delivers a CO yield of 240.55 μmol·g −1 and a CH 4 yield of 68.70 μmol·g -1 in pure water without sacrificial agents, representing ∼8.0-fold and ∼4.6-fold enhancements over pristine CN, respectively, superior to most reported single-atom photocatalysts. According to femtosecond transient absorption spectroscopy, theoretical calculation, and in situ techniques, the superior catalytic activity originates from the synergistic interaction between Dy and Co dual active sites. Specifically, Dy-possessing abundant unoccupied 4f orbitals-functions as an electron reservoir that facilitates directional electron transfer toward the Co sites, accelerating charge extraction by 8.4-fold and enhancing electron transfer kinetics by 1.5-fold. This electron enrichment at the Co centers induces a downshift in the Co d -band center, which further strengthens CO 2 adsorption and activation at the Co sites with inherent CO 2 affinity. In this paper, resent the lanthanide-empowered strategy to overcome charge dynamics limitations in cobalt single-atom catalysts. Dysprosium serves as an atomic electron reservoir adjacent to cobalt sites in dual sites centers, enabling synergistic CO2 reduction. Multimodal analysis (XAS, in situ spectroscopy, fs-TA, and DFT) reveals Dysprosium to cobalt electron transfer and d-band center optimization mechanisms. Download: Download high-res image (269KB) Download: Download full-size image