As an environmentally friendly and resource-rich energy, hydrogen is recognized as an ideal alternative to conventional fossil fuels. Among various methods for hydrogen production, electrochemical water splitting is one of the most promising approaches, for which hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are crucial for determining the performance. Recently, much research has shown heterostructure catalysts to possess competitive electrocatalytic performance toward HER and OER. However, compared with their theoretical activities, many heterostructure catalysts remain somewhat unsatisfactory and have a long way to go. With the aim of ultimately enhancing electrocatalytic performance, recent approaches for the modification of heterostructure catalysts are summarized in this review. Typical synthetic strategies, such as design of nanostructure, chemical doping, and heterostructure-based hybrids synthesis, are discussed, and their advantages are highlighted. Finally, perspectives on the future direction of heterostructure electrocatalysts toward water splitting are presented.

作为一种环境友好、资源丰富的能源，氢被公认为传统化石燃料的理想替代品。在各种制氢方法中，电化学水分解是最有前途的方法之一，其中析氢反应（HER）和析氧反应（OER）对性能的决定至关重要。最近，许多研究表明异质结构催化剂对 HER 和 OER 具有竞争性的电催化性能。然而，与其理论活性相比，许多异质结构催化剂仍然有些不尽人意，还有很长的路要走。为了最终提高电催化性能，本文总结了最近的异质结构催化剂改性方法。典型的合成策略，讨论了纳米结构的设计、化学掺杂和基于异质结构的杂化合成，并突出了它们的优势。最后，提出了异质结构电催化剂在水分解方面的未来发展方向。