The phenomenon of hydrogen spillover is a dynamic behavior during catalytic reactions and has been a prominent area of research in the field of thermal catalysis. This concept has become a new focus of research in the field of hydrogen evolution reaction (HER) in recent years. The hydrogen spillover effect has a pivotal effect on modulating the active sites of catalysts and enhancing catalytic activity, which also provides a novel perspective for optimizing HER catalysts. While some advancements have been achieved in understanding the hydrogen spillover phenomenon, the existing review is deficient in a systematic overview of the mechanism of hydrogen spillover occurrence during HER and a summary of the evidence to confirm the occurrence of the hydrogen spillover phenomenon particularly. Furthermore, a comprehensive summary of the specific strategies to optimize the catalytic system using this effect is lacking. In light of the aforementioned considerations, this review aims to conduct a comprehensive summary of the fundamental mechanisms underlying the phenomenon of hydrogen spillover, with a particular focus on the evidence presented in experimental studies. Following a comprehensive examination of the underlying mechanism and supporting evidence, the discussion turns to the question of how the hydrogen spillover effect can be strategically enhanced to optimize the overall performance of HER. Finally, the opportunities and challenges facing this research area are discussed, and potential future research directions are outlined. This review not only enhances comprehension of how hydrogen spillover occurs in the HER process but also offers invaluable theoretical insight and practical strategies for the creation of new and efficient catalysts.

中文翻译：

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揭开析氢反应中氢溢出现象的奥秘：基本原理、证据和增强策略


氢溢出现象是催化反应过程中的一种动态行为，一直是热催化领域的一个突出研究领域。这一概念近年来已成为析氢反应 （HER） 领域的新研究重点。氢溢出效应对调节催化剂的活性位点和增强催化活性具有关键作用，这也为优化 HER 催化剂提供了新的视角。虽然在理解氢溢出现象方面取得了一些进展，但现有的综述缺乏对 HER 期间氢溢出发生机制的系统概述以及特别确认氢溢出现象发生的证据总结。此外，缺乏对利用这种效应优化催化系统的具体策略的全面总结。鉴于上述考虑，本文旨在对氢溢出现象的基本机制进行全面总结，特别关注实验研究中提供的证据。在全面研究了潜在机制和支持证据之后，讨论转向了如何战略性地增强氢溢出效应以优化 HER 的整体性能的问题。最后，讨论了该研究领域面临的机遇和挑战，并概述了未来潜在的研究方向。这篇综述不仅增强了对 HER 过程中氢溢出如何发生的理解，还为创造新的高效催化剂提供了宝贵的理论见解和实用策略。