Non-trivial Topological Surface States Regulation of 1T-OsCoTe${}_2$ Enables Selective C-C Coupling for Highly Efficient Photochemical CO${}_2$ Reduction Toward C${}_{2+}$ hydrocarbons

Abstract

Despite ongoing research, the rational design of nontrivial topological semimetal surface states for the selective photocatalytic CO${}_2$ conversion into valuable products remains full of challenges. Herein, we present the synthesis of 1T-OsCoTe${}_2$ for the photoreduction upgrading of CO${}_2$ to tricarbon alkane C${}_3$H${}_8$,by the integration of experimental work and theory calculation. Experimental studies suggested a high electron based selectivity of 71.2% for C${}_3$H${}_8$ and an internal quantum efficiency of 54.6% at 380 nm. In-situ X-ray photoelectron spectroscopy and X-ray absorption fine structure spectroscopy demonstrated that Co and Os atoms coordinated with Te atoms enable an efficient Os-Te-Co electron transfer to activate the generation of *CH${}_3$,*CHOCO and *CH${}_2$OCOCO. Density functional theory calculations further confirmed Os-Te-Co electron bridging on the improved CO${}_2$ conversion kinetics. To our knowledge, this is the first report suggesting the role of Os atoms in accelerating the photocatalytic CO${}_2$ conversion activity of the topological semimetal 1T-OsCoTe${}_2$.

31 pages, 6 Figures