Ravi Parnapalle, Noh Jinseo
Bionano Research Institute, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si 13120, Gyeonggi-do, Korea.
Department of Physics, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si 13120, Gyeonggi-do, Korea.
Molecules. 2022 Oct 23;27(21):7176. doi: 10.3390/molecules27217176.
Solar water splitting (SWS) has been researched for about five decades, but despite successes there has not been a big breakthrough advancement. While the three fundamental steps, light absorption, charge carrier separation and diffusion, and charge utilization at redox sites are given a great deal of attention either separately or simultaneously, practical considerations that can help to increase efficiency are rarely discussed or put into practice. Nevertheless, it is possible to increase the generation of solar hydrogen by making a few little but important adjustments. In this review, we talk about various methods for photocatalytic water splitting that have been documented in the literature and importance of the thin film approach to move closer to the large-scale photocatalytic hydrogen production. For instance, when comparing the film form of the identical catalyst to the particulate form, it was found that the solar hydrogen production increased by up to two orders of magnitude. The major topic of this review with thin-film forms is, discussion on several methods of increased hydrogen generation under direct solar and one-sun circumstances. The advantages and disadvantages of thin film and particle technologies are extensively discussed. In the current assessment, potential approaches and scalable success factors are also covered. As demonstrated by a film-based approach, the local charge utilization at a zero applied potential is an appealing characteristic for SWS. Furthermore, we compare the PEC-WS and SWS for solar hydrogen generation and discuss how far we are from producing solar hydrogen on an industrial scale. We believe that the currently employed variety of attempts may be condensed to fewer strategies such as film-based evaluation, which will create a path to address the SWS issue and achieve sustainable solar hydrogen generation.
太阳能水分解（SWS）已经研究了大约五十年，但尽管取得了一些成功，却一直没有重大的突破性进展。虽然光吸收、电荷载流子分离与扩散以及氧化还原位点处的电荷利用这三个基本步骤分别或同时受到了大量关注，但有助于提高效率的实际考量却很少被讨论或付诸实践。然而，通过做出一些微小但重要的调整来增加太阳能制氢量是有可能的。在这篇综述中，我们讨论了文献中记载的各种光催化水分解方法，以及薄膜方法对于迈向大规模光催化制氢的重要性。例如，当将相同催化剂的薄膜形式与颗粒形式进行比较时，发现太阳能制氢量增加了高达两个数量级。这篇关于薄膜形式的综述的主要主题是，讨论在直接太阳光和一个太阳光照条件下增加产氢量的几种方法。还广泛讨论了薄膜技术和颗粒技术的优缺点。在当前的评估中，也涵盖了潜在的方法和可扩展的成功因素。正如基于薄膜的方法所表明的那样，零外加电势下的局部电荷利用对于太阳能水分解来说是一个有吸引力的特性。此外，我们比较了光电化学水分解（PEC-WS）和太阳能水分解（SWS）用于太阳能制氢的情况，并讨论了我们距离工业规模生产太阳能氢还有多远。我们相信，目前所采用的各种尝试可以浓缩为更少的策略，比如基于薄膜的评估，这将为解决太阳能水分解问题并实现可持续的太阳能制氢创造一条途径。
