Robust Tunnel TaO <sub>x</sub> Passivating Interlayer Enables Long‐Term Solar Water Oxidation
Abstract
Abstract Silicon‐based photoelectrochemical (PEC) cells offer significant advantages for solar‐to‐clean fuel conversion but face challenges such as surface recombination and poor stability, necessitating a comprehensive understanding of device failure mechanisms and effective mitigation strategies. Using nickel‐decorated n‐type silicon (n‐Si/Ni) as a model photoelectrode, we demonstrate that surface restructuring during operation initially passivates surface recombination but eventually blocks photogenerated hole transfer, leading to device failure. To mitigate this challenge, an ultrathin (<1 nm) tantalum oxide (TaO x ) interlayer is introduced via atomic layer deposition (ALD). This TaO x layer serves as both a passivating contact and a corrosion‐resistant coating. The n‐Si/TaO x /Ni electrode achieves an increased photovoltage from 150 to 500 mV during the activation process, and then significantly extends the device lifespan, maintaining over 90% performance for 500 h in 1 M KOH at 1.52 V versus RHE. These results highlight the implementation of amorphous TaO x in enhancing both the efficiency and durability of silicon‐based PEC systems, providing a simultaneously passivating and protective strategy for solar‐to‐fuel conversion technologies under harsh conditions.
Article Details
Authors (14)
Yuanqi Wang
National Laboratory of Solid State Microstructures School of Physics Nanjing University Nanjing 210093 P.R. China
Yinglei Zhu
Jiangsu Key Laboratory for Nano Technology College of Engineering and Applied Sciences Nanjing University Nanjing 210093 P.R. China
Lijuan Zhang
Huiting Huang
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Changhao Liu
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Bin Gao
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Wangxi Liu
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Huihui Yan
Jingrui Jian
State Key Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Nanjing China
Zengguang Huang
School of Science Jiangsu Ocean University Lianyungang 222005 P.R. China
Jianyong Feng
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Tao Yu
Zhigang Zou
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China
Zhaosheng Li
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China