Artificial Photosynthesis

We are researching artificial photosynthesis with inorganic semiconductor. The hole-electron pair produced by photo-illuminations drives redox reactions on the each electrode that is anode and cathode. Redox reactions mean water splitting and CO2 reduction that produce HCOOH, CO, and CH4 from CO2. This technology has potential to develop environmental and energy problem due to energy conversion from solar to chemical energy.

Many researcher studied with TiO2 which is stable and rich material. But it can only absorb ultra-violet light power because of wide band-gap. Furthermore, it doesn’t drive CO2 reduction because of insufficient potential. In this reason, we focus on silicon carbide (SiC) because SiC has a proper band-gap for CO2 reduction. Our goal is producing semiconductor device with high stability and high efficient for artificial photosynthesis.

Basic principle of research
Fig.1 Solid-liquid junction band diagram
Comparison of band gap structure for semiconductor material
Fig.2 Energy levels refer to redox reactions