Wydarzenia

Seminarium Wrocławskiego Centrum Badań EIT+

Development of semiconductor photocatalyst for clean energy evolution by multidisciplinary approaches

prof. Kazuhiro Ohkawa

King Abdullah University of Science and Technology (KAUST) Thuwal, Saudi Arabia

Abstract

Nitride semiconductors are attractive materials not only for efficient L(E)D lighting but also clean energy generator. Nitride photocatalyst split water into H₂ and O₂ gasses by using light energy without external bias. This catalyst also can reduce CO₂ molecules become hydrocarbons such as HCOOH, CH₄, C₂H₅OH. These phenomena realize clean energy generation by using natural energy, i.e. solar light. The key technologies are metalorganic vapor-phase epitaxy (MOVPE) growth of high-quality InGaN and invention of NiO co-catalyst on nitride photocatalyst. Co-catalyst materials could stop photo-corrosion and enhance water oxidation. Energy conversion efficiency is already more than average of biological photosynthetic one. These phenomena are valuable not only for chemists but also physicists, electrical engineers. That is multidisciplinary: material growth is chemistry; photo-absorption is physics; carrier transport is electrical engineering; reactions are chemistry. Many scientists can contribute this field.

Biography

Dr. Kazuhiro Ohkawa is a professor at KAUST from 2016. His research field is optical-chemical devices such as LEDs, laser diodes, and photocatalyst based on nitride semiconductors. He invented nitride photocatalyst and raised temperature MOVPE. Also, he had established growth simulation of nitride MOVPE when he was a professor at Tokyo University of Science (Japan, 1998-2016). He studied II-VI LEDs and lasers and invented p-type (Nitrogen-plasma source) and n-type doping methods when he was a professor at University of Bremen (Germany, 1996-1998), and a senior research staff at Panasonic (Japan, 1985-1996).