相对于贵金属电催化剂制作成本高、地球储量稀少、电化学稳定性低等缺点，制备廉价、能量转换效率高、使用寿命长、环境友好的非贵金属电催化剂是推动能源存储和转换技术快速发展的重要途径。根据电催化过程中电催化析氢反应(Hydrogen Evolution Reaction，HER)、电催化析氧反应(Oxygen Evolution Reaction，OER)及氧还原反应(Oxygen Reduction Reaction，ORR)这三个重要反应类型，概述了水裂解和燃料电池的电化学反应机制，同时归纳了单功能电催化剂、双功能电催化剂、多功能电催化剂及其他电化学材料的设计与制备方法、相互关系和各自功能特点。借助先进的电子显微技术，如扫描电子显微镜、原子力扫描电子显微镜、透射电子显微镜、X射线能谱仪、电子能量损失谱仪等对其微观结构进行表征，重点对其表面形貌、结构、内部成分、元素分布等相关信息进行解析。从提供更丰富的缺陷空位、潜在活性位点、优化界面相互作用、增大电化学比表面积、形成协同效应等方面，分析其在降低成本的同时，提高电催化剂的电导率、增强稳定性的相关机理，以期为非贵金属电催化剂的研究和推广应用提供新策略。

Compared with the high production cost, rare earth reserves and low electrochemical stability of noble metal electrocatalysts, the preparation of non-noble metal electrocatalysts with low cost, high energy conversion efficiency, long service life and environmental friendliness is an important way to promote the development of energy storage and conversion technology. This paper reviewed monofunctional electrocatalysts, bifunctional electrocatalysts and multifunctional electrocatalysts for three important reactions in electrocatalytic process, i.e., hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The electrochemical reaction mechanisms of water splitting and fuel cell were introduced, respectively. The design, preparation, relationship and functional characteristics was described for the monofunctional electrocatalysts, bifunctional electrocatalysts and multifunctional electrocatalysts and other electrochemical materials. The systematical characterization and resolving were performed on these promising non-noble metal electrocatalysts by using scanning electron microscopy, atomic force scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, electron energy loss spectroscopy and other complementary techniques. The surface morphology, structure, internal composition, elemental distribution and other related information were also analyzed. From the aspects of providing more defect vacancies and potential active sites, optimizing interface interaction, increasing electrochemical specific surface area, functionalizing synergistic effect, the mechanisms of improving conductivity and enhancing stability of electrocatalyst as well as reducing cost were analyzed. Expectedly, it largely promotes their large-scale applications in those involved electrochemical energy conversion and storage.