Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore.
Sci Rep. 2012;2:451. doi: 10.1038/srep00451. Epub 2012 Jun 12.
TiO₂ nanostructures-based photoelectrochemical (PEC) cells are under worldwide attentions as the method to generate clean energy. For these devices, narrow-bandgap semiconductor photosensitizers such as CdS and CdSe are commonly used to couple with TiO₂ in order to harvest the visible sunlight and to enhance the conversion efficiency. Conventional methods for depositing the photosensitizers on TiO₂ such as dip coating, electrochemical deposition and chemical-vapor-deposition suffer from poor control in thickness and uniformity, and correspond to low photocurrent levels. Here we demonstrate a new method based on atomic layer deposition and ion exchange reaction (ALDIER) to achieve a highly controllable and homogeneous coating of sensitizer particles on arbitrary TiO₂ substrates. PEC tests made to CdSe-sensitized TiO₂ inverse opal photoanodes result in a drastically improved photocurrent level, up to ~15.7 mA/cm² at zero bias (vs Ag/AgCl), more than double that by conventional techniques such as successive ionic layer adsorption and reaction.
基于 TiO₂ 纳米结构的光电化学（PEC）电池作为一种产生清洁能源的方法受到了全世界的关注。对于这些设备，通常使用窄带隙半导体敏化剂，如 CdS 和 CdSe，与 TiO₂ 耦合，以捕获可见光并提高转换效率。传统的在 TiO₂ 上沉积敏化剂的方法，如浸涂、电化学沉积和化学气相沉积，在厚度和均匀性方面控制不佳，对应于低光电流水平。在这里，我们展示了一种基于原子层沉积和离子交换反应（ALDIER）的新方法，以实现对任意 TiO₂ 基底上敏化剂颗粒的高度可控和均匀的涂覆。对 CdSe 敏化的 TiO₂ 反蛋白石光阳极进行的 PEC 测试导致光电流水平显著提高，在零偏压（相对于 Ag/AgCl）下达到约 15.7 mA/cm²，是传统技术（如连续离子层吸附和反应）的两倍多。
