Department of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000, PR China.
Key Laboratory of Hunan Province on Information Photonics and Freespace Optical Communications, School of Physics and Electronic Science, Hunan Institute of Science and Technology, Yueyang 414006, China.
J Nanosci Nanotechnol. 2021 Nov 1;21(11):5642-5647. doi: 10.1166/jnn.2021.19465.
In this work, UV light activated multi-cycle photoelectric properties of TiO₂ and CdS/TiO₂ films in formaldehyde were researched. TiO₂ film was prepared by screen printing, CdS/TiO₂ compounded film was synthesized by SILAR method. XRD and FE-SEM was used to characterize the TiO₂ and CdS/TiO₂ samples. Multi-cycle photoelectric properties of TiO₂ and CdS/TiO₂ with uv light on and off were evaluated by testing the photocurrent. On one hand, under the same bias voltage, CdS/TiO ₂showed a higher photocurrent than that by TiO₂. The reason for this result should be ascribed to the compounded structure in CdS/TiO₂, with which the separation and transfer of photogenerated electron-hole pairs could be improved. On the other hand, with the testing cycle number increased, the photocurrent amplitudes of TiO₂ and CdS/TiO₂ increased. These results suggested that the time to reach a stable photocurrent value for TiO₂ and CdS/TiO₂ is much longer than one cycle time (300 S). To illustrate the increased photocurrent amplitude value cycle by cycle, the photocurrent of CdS/TiO₂ to a much longer time (more than 4000 seconds) was also tested. To explain these results, corresponding possible illustrations were presented.
在这项工作中，研究了 TiO₂ 和 CdS/TiO₂ 薄膜在甲醛中的光激活多循环光电性能。TiO₂ 薄膜通过丝网印刷制备，CdS/TiO₂ 复合薄膜通过 SILAR 法合成。XRD 和 FE-SEM 用于表征 TiO₂ 和 CdS/TiO₂ 样品。通过测试光电流评估了 TiO₂ 和 CdS/TiO₂ 在紫外光照射和关闭下的多循环光电性能。一方面，在相同的偏置电压下，CdS/TiO₂ 表现出比 TiO₂ 更高的光电流。这一结果的原因应归因于 CdS/TiO₂ 的复合结构，通过该结构可以提高光生电子-空穴对的分离和转移。另一方面，随着测试循环次数的增加，TiO₂ 和 CdS/TiO₂ 的光电流幅度增加。这些结果表明，TiO₂ 和 CdS/TiO₂ 达到稳定光电流值所需的时间远长于一个循环时间（300 s）。为了说明光电流幅度逐次增加，还测试了 CdS/TiO₂ 的光电流达到更长时间（超过 4000 秒）。为了解释这些结果，提出了相应的可能说明。
