Dalla Valle Paul, Cavassilas Nicolas
Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334 13397 Marseille France
Nanoscale Adv. 2022 May 14;4(13):2816-2822. doi: 10.1039/d2na00178k. eCollection 2022 Jun 28.
Solar water splitting (SWS) has been widely studied as a promising technology for generating carbon-free hydrogen. In this article, we propose an unassisted SWS system based on van der Waals heterojunctions using monolayers of transition metal dichalcogenides as active core materials. This architecture, with its small band gap materials and high surface/volume ratio, has an intrinsic type-II band alignment that offers many advantages, such as direct Z-scheme configuration and wide absorption. To estimate the solar-to-hydrogen (STH) efficiency of the system, we developed a multiphysics model. While electronic and optical properties are computed with calculations, we implemented the detailed balance method and the Butler-Volmer kinetics to simulate the photoelectrochemical behaviour. Under realistic operating conditions, the system achieves a STH efficiency greater than 15%, which is higher than the critical 10% efficiency required to make SWS economically viable. Since our system is wireless and requires simple manufacturing processes (exfoliation), this result is remarkable.
太阳能水分解（SWS）作为一种有前景的无碳制氢技术已得到广泛研究。在本文中，我们提出了一种基于范德华异质结的无辅助SWS系统，该系统使用过渡金属二硫属化物单层作为活性核心材料。这种结构具有小带隙材料和高表面/体积比，具有本征II型能带排列，具有许多优点，如直接Z型配置和宽吸收。为了估计该系统的太阳能到氢能（STH）效率，我们开发了一个多物理模型。在用计算方法计算电子和光学性质的同时，我们采用了详细平衡法和巴特勒-伏尔默动力学来模拟光电化学行为。在实际操作条件下，该系统实现了大于15%的STH效率，高于使SWS在经济上可行所需的临界10%效率。由于我们的系统是无线的，并且需要简单的制造工艺（剥离），这个结果非常显著。
