Zeradjanin Aleksandar R, Polymeros George, Toparli Cigdem, Ledendecker Marc, Hodnik Nejc, Erbe Andreas, Rohwerder Michael, La Mantia Fabio
Universität Bremen, Energiespeicher- und Energiewandlersysteme, Bibliothekstr. 1, 28359, Bremen, Germany.
Max-Planck-Institut für Eisenforschung GmbH, Department of Interface Chemistry and Surface Engineering, Max-Planck-Strasse 1, 40237 Düsseldorf, Germany.
Phys Chem Chem Phys. 2020 Apr 29;22(16):8768-8780. doi: 10.1039/d0cp01108h.
The mechanism of the hydrogen evolution reaction, although intensively studied for more than a century, remains a fundamental scientific challenge. Many important questions are still open, making it elusive to establish rational principles for electrocatalyst design. In this work, a comprehensive investigation was conducted to identify which dynamic phenomena at the electrified interface are prerequisite for the formation of molecular hydrogen. In fact, what we observe as an onset of the macroscopic faradaic current originates from dynamic structural changes in the double layer, which are entropic in nature. Based on careful analysis of the activation process, an electrocatalytic descriptor is introduced, evaluated and experimentally confirmed. The catalytic activity descriptor is named as the potential of minimum entropy. The experimentally verified catalytic descriptor reveals significant potential to yield innovative insights for the design of catalytically active materials and interfaces.
析氢反应的机理，尽管已经经过了一个多世纪的深入研究，但仍然是一个基本的科学挑战。许多重要问题仍然悬而未决，这使得难以建立合理的电催化剂设计原则。在这项工作中，进行了全面的研究，以确定在带电界面处哪些动态现象是分子氢形成的先决条件。事实上，我们观察到的宏观法拉第电流的起始源于双层中的动态结构变化，其本质是熵性的。基于对活化过程的仔细分析，引入、评估并通过实验证实了一个电催化描述符。该催化活性描述符被命名为最小熵电势。经实验验证的催化描述符显示出为催化活性材料和界面的设计产生创新见解的巨大潜力。
