Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-58183 Linköping, Sweden.
College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, and Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou 515063, P. R. China.
ACS Appl Mater Interfaces. 2023 May 3;15(17):21057-21065. doi: 10.1021/acsami.3c01476. Epub 2023 Apr 20.
Photoelectrochemical (PEC) water splitting for hydrogen production using the CdTe photocathode has attracted much interest due to its excellent sunlight absorption property and energy band structure. This work presents a study of engineered interfacial energetics of CdTe photocathodes by deposition of CdS, TiO, and Ni layers. A heterostructure CdTe/CdS/TiO/Ni photocathode was fabricated by depositing a 100-nm -type CdS layer on a -type CdTe surface, with 50 nm TiO as a protective layer and a 10 nm Ni layer as a co-catalyst. The CdTe/CdS/TiO/Ni photocathode exhibits a high photocurrent density () of 8.16 mA/cm at 0 V versus reversible hydrogen electrode (V) and a positive-shifted onset potential () of 0.70 V for PEC hydrogen evolution under 100 mW/cm AM1.5G illumination. We further demonstrate that the CdTe/CdS - junction promotes the separation of photogenerated carriers, the TiO layer protects the electrode from corrosion, and the Ni catalyst improves the charge transfer across the electrode/electrolyte interface. This work provides new insights for designing noble metal-free photocathodes toward solar hydrogen development.
光电化学（PEC）水分解制氢利用 CdTe 光阴极引起了广泛关注，因为其具有优异的太阳光吸收特性和能带结构。本工作通过沉积 CdS、TiO 和 Ni 层研究了 CdTe 光阴极的工程界面能态。通过在 - 型 CdTe 表面沉积 100nm 的 - 型 CdS 层，制备了 CdTe/CdS/TiO/Ni 异质结构光阴极，其中 50nm 的 TiO 作为保护层，10nm 的 Ni 层作为共催化剂。CdTe/CdS/TiO/Ni 光阴极在 100mW/cm AM1.5G 光照下，0V 时的光电流密度（）达到 8.16mA/cm，PEC 析氢的起始电位（）正向移动至 0.70V。我们进一步证明，CdTe/CdS 结促进了光生载流子的分离，TiO 层保护电极免受腐蚀，Ni 催化剂提高了电极/电解质界面的电荷转移。这项工作为设计无贵金属的光阴极以实现太阳能制氢提供了新的见解。
