▎ 摘　　要

NOVELTY - Preparing defect foam graphene-supported transition metal single atom catalyst comprises (i) adding graphene oxide to nitric acid solution, etching for many hours, washing in deionized water to neutral, drying to obtain defect graphene oxide; (ii) introducing nitrogen source on surface of defect graphene oxide, stirring by transition metal salt solution, re-dispersing obtained product in solution, washing sample obtained by microwave radiation in deionized water, soaking product with hydrochloric acid solution, washing to neutral and dispersing in aqueous solution to obtain defect graphene oxide load transition metal single atom solution; and (iii) ultrasonically dispersing defect graphene oxide load transition metal single atom solution, pouring to hydrothermal reaction kettle to high temperature reduction, freezing and drying, performing high temperature annealing treatment under argon gas atmosphere, soaking in hydrochloric acid solution, washing to neutral, freezing and drying. USE - The defect foam graphene-supported transition metal single atom catalyst is useful in synthesis of ammonia by nitrogen reduction (claimed). ADVANTAGE - The method: can enables preparation of defect foam graphene-loaded transition metal single-atom catalyst having excellent catalytic activity, durability and stability.