(Invited) P-Type 3C-SiC Photocathode for Solar to Hydrogen Energy Conversion

Silicon carbide (SiC) is a chemically stable and photocatalytic semiconductor material. Among SiC polytypes, 3C-SiC has the smallest band gap (2.3 eV), and thus 3C-SiC is capable to absorb a significant part of solar light. The use of p-type semiconductor as photocathode reduces hydrogen in water. Cathodic operation prevents oxidation of photocatalytic materials. Therefore p-type 3C-SiC will be an efficient and durable photocatalyst. Our experiments have revealed that p-type 3C-SiC acts as photocathodes with excellent performance. Solar to hydrogen conversion efficiency for p-type 3C-SiC photocathodes with Pt cocatalysts was 0.52 %. Considering such a high efficiency and possibility of further improvement, SiC is a very promising material for the solar to hydrogen conversion technology.