| 초록 |
Electrochemical CO2 reduction has been widely investigated due to potential applications for solar energy-storing devices. Inspired from photosynthesis in nature, photoelectrochemical (PEC) conversion system is suggested to use CO2 and H2O as feedstock chemicals for the production of solar fuels in a feasible manner. Herein, we demonstrate a PEC CO2 reduction platform in which an electrode composed of Bi nanostructures as reduction catalysts is powered by monolithic CuInGaS2 thin-film solar cells in aqueous media. Specifically, Bi nanostructures were prepared by electrochemical synthetic method on solid substrates to increase CO2 reduction activities with selective production for formic acid (HCOOH), and CuInGaS2 thin-film solar cell was fabricated by low-cost solution-based preparation method whose high open-circuit voltage is desirable to overcome high overpotential of CO2 reduction reaction. Furthermore, the product selectivity, the energy conversion efficiency, and the stability of the electrode were dramatically enhanced. This Bi electrocatalyst exhibited total faradaic efficiencies of CO2 to C1 chemicals (e.g. carbon monoxide and formic acid) of over 80%, and possible mechanistic pathways were discussed. |
