title: Unique Three-Dimensional InP Nanopore Arrays for Improved Photoelectrochemical Hydrogen Production.
abstract: Ordered three-dimensional (3D) nanostructure arrays hold promise for high-performance energy harvesting and storage devices. Here, we report the fabrication of InP nanopore arrays (NPs) in unique 3D architectures with excellent light trapping characteristic and large surface areas for use as highly active photoelectrodes in photoelectrochemical (PEC) hydrogen evolution devices. The ordered 3D NPs were scalably synthesized by a facile two-step etching process of (1) anodic etching of InP in neutral 3 M NaCl electrolytes to realize nanoporous structures and (2) wet chemical etching in HCl/H3PO4 (volume ratio of 1:3) solutions for removing the remaining top irregular layer. Importantly, we demonstrated that the use of neutral electrolyte of NaCl instead of other solutions, such as HCl, in anodic etching of InP can significantly passivate the surface states of 3D NPs. As a result, the maximum photoconversion efficiency obtained with ∼15.7 μm thick 3D NPs was 0.95%, which was 7.3 and 1.4 times higher than that of planar and 2D NPs. Electrochemical impedance spectroscopy and photoluminescence analyses further clarified that the improved PEC performance was attributed to the enhanced charge transfer across 3D NPs/electrolyte interfaces, the improved charge separation at 3D NPs/electrolyte junction, and the increased PEC active surface areas with our unique 3D NP arrays.
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Qiang
authors: Q
authors: Li
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.|Collaborative Innovation Center of Advanced Microstructures , Nanjing 210093, People's Republic of China.
authors: Maojun
authors: M
authors: Zheng
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Liguo
authors: L
authors: Ma
authors: Department of Chemical System Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors: Miao
authors: M
authors: Zhong
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Changqing
authors: C
authors: Zhu
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Bin
authors: B
authors: Zhang
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Faze
authors: F
authors: Wang
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Jingnan
authors: J
authors: Song
authors: School of Chemistry and Chemical Technology, Shanghai Jiao Tong University , Shanghai 200240, People's Republic of China.
authors: Li
authors: L
authors: Ma
authors: Key Laboratory of Artificial Structure and Quantum Control, Ministry of Education, Department of Physics and Astronomy, Shanghai Jiao Tong University , Shanghai, 200240, People's Republic of China.
authors: Wenzhong
authors: W
authors: Shen
keywords: InP; anodic etching; nanopore arrays; photoelectrochemical cells; three-dimensional