cs0c00947_si_001.pdf (1.17 MB)
(Photo)Electrocatalytic CO2 Reduction at the Defective Anatase TiO2 (101) Surface
journal contribution
posted on 2020-03-13, 18:46 authored by Ji-Yuan Liu, Xue-Qing Gong, Ruoxi Li, Haotian Shi, Stephen B. Cronin, Anastassia N. AlexandrovaExcessive
carbon dioxide (CO2) emissions by combustion
of fossil fuels are linked to global warming and rapid climate change.
One promising route to lowering the concentration of CO2 in the atmosphere is to reduce it to useful small molecules via
photoelectrocatalytic hydrogenation, which would enable solar energy
storage with a zero-carbon emission cycle and perform a more efficient
separation of the photogenerated electron and hole pair than pure
photocatalysis. Indeed, photoelectrocatalytic CO2 reduction
has been an intense focus of research. Using the density functional
theory (DFT), we studied the CO2 reduction reaction on
the defective anatase TiO2 (101) surface, at both the solvent/catalyst
and the electrolyte/catalyst interfaces. The analysis of the electronic
structure of the surface shows a contrast between the solvent/catalyst
and the electrolyte/catalyst interfaces, which results in the two
corresponding catalytic cycles being distinct. Our study explains
at the electronic and mechanistic levels why methanol is the main
product in the presence of the electrolyte and why the overpotential
is not only controlled by the reaction process but also by the diffusion
process.