LBNL 한인 모임
양우석 박사.jpg Abstract: Photoelectrochemical (PEC) water splitting has drawn much attention as a cost-effective technique to accomplish solar hydrogen production. In order to reduce the cost of solar hydrogen, earth-abundant light absorber materials are needed that can be fabricated with low-cost solution processing. In this talk, I will give a brief overview of recent progress in low-cost photocathodes with recent works on antimony selenide (Sb2Se3) photocathode in our group. Sb2Se3 is an attractive one due to the narrow band gap of 1.0 – 1.3 eV, high absorption coefficient (>105 cm-1) and high hole mobility. The shape-controlled Sb2Se3 nanostructures were fabricated via a facile spin-coating with molecular inks and unique growth mechanism of Sb2Se3 nanostructures was elucidated in conjunction with specific molecular chemistry. With the controlled shaped Sb2Se3 nanostructures, the subsequent deposition of protection layer (TiO2) and co-catalyst (Pt, RuOx, MoSx) enabled us to demonstrate the first hydrogen production from Sb2Se3 based photocathode. In addition, carrier dynamics in Sb2Se3 photocathodes determined by THz spectroscopy, time-resolved photoluminescence and intensity modulated photocurrent/voltage spectroscopy, will be presented.

BIO: Dr. Wooseok Yang, who is a postdoctoral researcher at Yonsei University, is working on developing solution-processed earth-abundant materials for photoelectrochemical water splitting. He received Ph. D. in Materials Science and Engineering at Yonsei University and has BS in Ceramic Engineering from Yonsei University, South Korea.