Remarkable enhancement in photocurrent of In0.20Ga0.80N photoanode by using an electrochemical surface treatment

The photocurrent and incident photon conversion efficiency of In0.20Ga0.80N increased about 2 times after a simple electrochemical surface treatment. X-ray photoelectron spectroscopy and photoluminescence analysis suggested that In-rich InGaN region on the surface of the In0.20Ga0.80N electrode was removed by using the electrochemical surface treatment. The enhancement of the photocurrent was attributed to the removal of In-rich InGaN phases caused by indium segregations on the surface of the electrode, which played a major role as surface recombination centers of photo-generated electron-hole pairs. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3640223]