Photoelectrochemical oxygen evolution improved by a thin Al2O3 interlayer in a NiOx/n-Si photoanode

Publication date: 29 January 2016
Source:Thin Solid Films, Volume 599
Author(s): Min-Joon Park, Jin-Young Jung, Sun-Mi Shin, Jae-Won Song, Yoon-Ho Nam, Dong-Hyung Kim, Jung-Ho Lee
We employ a thin Al2O3 interlayer between p-NiOX catalyst/n-Si photoanode interfaces to realize an effective oxygen evolution reaction (OER). The Al2O3 interlayer is used to reduce the interface defect density, enhance the band bending by suppressing the Fermi-level pinning effect, and enhance photovoltage at the catalyst/semiconductor rectifying junction. Our NiOX/Al2O3/n-Si photoanodes generated a photocurrent of 3.36mA/cm² at the equilibrium potential of OER (EOER =1.23V vs. reversible hydrogen electrode in 1M NaOH solution) and a solar-to-oxygen conversion efficiency of 0.321%. Moreover, the photoanode showed no sign of decay over 20h of photoelectrochemical water oxidation.