Hydrogen evolution technology by photocatalysts has shown broad prospects in solving the global energy crisis and environmental pollution problems. Cadmium sulfide (CdS) heterojunctions have been concerned as a promising photocatalyst because of its suitable band location, but many challenges are still standing on the way to achieve high photoelectric conversion efficiency and hydrogen evolution activity, such as high carrier recombination rate and poor stability. In this paper, the latest achievements on CdS heterojunctions for hydrogen production were traced. Focusing on the key role of the structure of CdS heterojunctions, the separation and transport of photogenerated charges and hydrogen evolution dynamics during water reduction by CdS heterojunctions photocathode were discussed. Based on the decisive role of material structure on their photovoltaic performance, CdS heterojunctions were divided into three types according to different dimensions, i.e. one dimension, two dimension and three dimension, and their performance characteristics, synthesis methods and application properties were introduced respectively. Finally, the challenges on how to improve the photocatalytic hydrogen evolution efficiency using CdS heterojunctions were brought forward and the structural improvement strategies on designing CdS heterojunctions were proposed. We hope that this review will provide a reference and guidance for the audiences in the field of photocatalysis.

中文翻译：

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CdS异质结的最新进展：形态、合成、性能和前景

光催化剂析氢技术在解决全球能源危机和环境污染问题方面显示出广阔的前景。硫化镉（CdS）异质结因其合适的能带位置而被认为是一种有前途的光催化剂，但在实现高光电转换效率和析氢活性方面仍面临许多挑战，例如高载流子复合率和稳定性差。本文综述了CdS异质结制氢的最新进展。围绕CdS异质结结构的关键作用，讨论了CdS异质结光阴极光生电荷的分离与传输以及水还原过程中的析氢动力学。基于材料结构对其光伏性能的决定性作用，根据不同维度将CdS异质结分为一维、二维和三维三种类型，并分别介绍了它们的性能特点、合成方法和应用特性。最后，提出了如何利用CdS异质结提高光催化析氢效率的挑战，并提出了设计CdS异质结的结构改进策略。我们希望这篇综述能够为光催化领域的观众提供参考和指导。