The electrocatalytic process mainly occurs on the surface of the electrocatalysts, the property is dominated by the surface characteristics of the catalyst. Thus, surface design and regulation of electrocatalysts are of critical importance in the design of catalyst. From the perspective of defect chemistry, our team realized the regulation of the surface atomic arrangement structure of the catalyst and improved the electrocatalytic performance of the catalyst. Our team has opened up the direction of "defect chemistry of electrocatalyst". In this field, we have achieved systematic innovation research results and are in a leading position in the world. Through the construction of catalyst surface defects, we designed high-performance electrocatalyst, learned the mechanism of defects, understood the structure-activity relationship between defect and catalytic property, constructed its application basis in catalyst design and provided theoretical basis for the design of new catalysts.