Proton reduction is a critical reaction for the efficient utilization of solar fuels and the development of a hydrogen economy. Molecular proton reduction catalysts help us to understand how hydrogenases function in nature, on one hand, and inspire us to design new practical materials on the other. This manuscript introduces the concept of electrocatalytic and photocatalytic proton (hydrogen evolution) in a homogeneous system, and then reviews recent studies on molecular proton reduction catalysts that contain 3d transition metal centers (Mn, Fe, Co, and Ni) surrounded by polypyridine ligands. The discussion focuses on the design, structure, and catalytic behavior of these metal polypyridine catalysts. Catalytic pathways, and how they are affected by complex structure, are addressed in order to offer rational suggestions for the future preparation of promising hydrogen evolution catalysts.

减少质子是有效利用太阳能和发展氢经济的关键反应。分子质子还原催化剂一方面帮助我们了解氢化酶在自然界中的功能，另一方面又激发我们设计新的实用材料。该手稿介绍了均相系统中电催化和光催化质子（氢的逸出）的概念，然后回顾了有关含3d分子质子还原催化剂的最新研究。过渡金属中心（Mn，Fe，Co和Ni）被聚吡啶配体包围。讨论的重点是这些金属聚吡啶催化剂的设计，结构和催化性能。提出了催化途径及其如何受复杂结构影响的问题，以便为将来有希望的析氢催化剂的制备提供合理的建议。