Materials Research Laboratory, University of Nova Gorica, SI-5000 Nova Gorica, Slovenia.
ACS Appl Mater Interfaces. 2013 Feb;5(3):1113-21. doi: 10.1021/am3027986. Epub 2013 Jan 29.
We report the photoelectrochemical (PEC) performance of textured porous ZnO and CdX-coated ZnO films (X = S, Se). Porous ZnO films were grown with a platelike morphology on F-doped SnO(2) (FTO) substrates. The growth of ZnO films involves a two-step procedure. In the first step, we electrochemically grew simonkolleite (Zn(5)(OH)(8)Cl(2)·H(2)O) plate films. Annealing of the simonkolleite at 450 °C results in textured porous ZnO films. The as-obtained porous ZnO electrodes were then used in PEC studies. To increase the light-harvesting efficiency, we sensitized these ZnO electrodes with CdS and CdSe quantum dots, using the so-called "successive ion layer adsorption and reaction (SILAR) method". As expected, the photocurrent density systematically increases when going from ZnO to ZnO/CdS to ZnO/CdSe. The highest photocurrent, ∼3.1 mA/cm(2) at 1.2 V vs RHE, was obtained in the CdSe-sensitized ZnO electrodes, because of their enhanced absorption in the visible range. Additionally, quantum efficiency values as high as 90% were achieved with the textured porous ZnO films. These results demonstrate that both CdS and CdSe-sensitized textured porous ZnO electrodes could be potentially useful materials in light-harvesting applications.
我们报告了具有纹理多孔 ZnO 和 CdX（X = S、Se）涂层的光电化学（PEC）性能。多孔 ZnO 薄膜在 F 掺杂的 SnO2（FTO）衬底上以片状形态生长。ZnO 薄膜的生长涉及两步程序。在第一步中，我们电化学生长了水锌矿（Zn(5)(OH)(8)Cl2·H2O）板状薄膜。将水锌矿在 450°C 下退火会导致具有纹理多孔 ZnO 薄膜。然后，将获得的多孔 ZnO 电极用于 PEC 研究。为了提高光捕获效率，我们使用所谓的“连续离子层吸附和反应（SILAR）法”将这些 ZnO 电极敏化 CdS 和 CdSe 量子点。不出所料，当从 ZnO 到 ZnO/CdS 再到 ZnO/CdSe 时，光电流密度会系统增加。在 CdSe 敏化的 ZnO 电极中，获得了最高的光电流，约为 1.2 V vs RHE 时的 3.1 mA/cm2，因为它们在可见光范围内的吸收增强。此外，多孔 ZnO 薄膜的量子效率值高达 90%。这些结果表明，CdS 和 CdSe 敏化的纹理多孔 ZnO 电极都可能是光捕获应用中有用的潜在材料。
