We demonstrated that the selectivity of photo electrochemical CO 2 reduction can be controlled in an inorganic artificial photosynthesis system using an AlGaN/GaN photo electrode. By increasing input light intensity and the use of a gold cathode, the Faradaic efficiency of CO dramatically increases from 30% to over 80% while that of H2 decreases. We observed that the cathode potential resulting from illumination determines the ratio of CO and H2. With this system, it is possible to switch the main reaction product from CO to HCOOH, which is also effective even under intense illumination.
ASJC Scopus subject areas
- Physics and Astronomy(all)