Materials Engineering, McGill University, 3610 University Street, Montreal, QC, Canada H3A 0C5.
Nanoscale. 2017 Jun 8;9(22):7650-7665. doi: 10.1039/c7nr01422h.
CuZnSnS (CZTS), other than in standard p-n junction device architecture, can be employed as a broad light absorber upon coating onto a wide bandgap electron conducting TiO film. Earlier CZTS sensitized TiO films have yielded low photoconversion efficiency and V. In this work, a water-ethanol solution spin coating approach has been applied to directly deposit CZTS nanocrystallites on rutile TiO nanorods grown on an FTO substrate (TNR) for evaluation in a sensitized solar cell configuration. The FTO@TNR@CZTS photoanode following controlled annealing is shown to exhibit improved photovoltaic properties. Focused-ion beam cross-sections of CZTS nanocoating onto TiO nanorod forest films have revealed nanoscale morphological details and electrochemical impedance spectroscopy helped identify TiO nanorod film growth characteristics for a reduced charge recombination. The band alignment of CZTS and TiO has been determined by XPS helping to explain the origin of V deficit. An all-solid state device featuring spiro OMeTAD as HTM and CdS as a buffer layer has been designed with 2% efficiency.
除了在标准的 p-n 结器件结构中，CuZnSnS（CZTS）也可以在涂覆到宽带隙电子传输 TiO 膜上时作为宽光吸收体。早期的 CZTS 敏化 TiO 薄膜的光电转换效率和开路电压（Voc）都较低。在这项工作中，采用水-乙醇溶液旋涂法直接在 FTO 基底上生长的锐钛矿 TiO 纳米棒（TNR）上沉积 CZTS 纳米晶，以评估敏化太阳能电池的配置。经过控制退火的 FTO@TNR@CZTS 光阳极表现出了改进的光伏性能。聚焦离子束的 CZTS 纳米涂层在 TiO 纳米棒森林薄膜上的横截面揭示了纳米级的形态细节，电化学阻抗谱有助于确定 TiO 纳米棒薄膜的生长特性，以减少电荷复合。XPS 确定了 CZTS 和 TiO 的能带排列，有助于解释 Voc 亏损的原因。采用 spiro OMeTAD 作为空穴传输材料和 CdS 作为缓冲层的全固态器件的设计效率为 2%。
