Ultraviolet photoelectrochemical photodetector based on GaN/Cu2O core–shell nanowire p–n heterojunctions
Mingrui Luo,
Jiaxun Song,
Jialin Wang,
Xingchen Pan,
Hao Hong,
Richard Nötzel
Affiliations
Mingrui Luo
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
Jiaxun Song
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
Jialin Wang
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
Xingchen Pan
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
Hao Hong
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
Richard Nötzel
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People’s Republic of China
An efficient, self-powered ultraviolet photoelectrochemical photodetector based on n-GaN/p-Cu2O core–shell nanowire p–n heterojunctions is demonstrated. The photocurrent under solar light is 2–3 times larger than that for GaN nanowires. The photocurrents under the solar light and the ultraviolet light fraction are comparable, 100 µA/cm2 photocurrent density. The photocurrent under the broad visible light part is about 3% of that under solar light. The responsivity and specific detectivity reach 961.5 µA/W and 5.35 × 109 Jones under ultraviolet light, respectively. The rise/fall times are 42/65 ms. This is understood by efficient photocarrier separation, hole collection, and transport in the near-surface GaN/Cu2O p–n heterojunction.
