▎ 摘　　要

NOVELTY - Tungsten single-atom catalyst having graphene substrate is claimed. The catalyst is obtained by uniformly dispersing few-layer graphene, and metal tungsten on the surface of the substrate graphene in the form of single atom. USE - The catalyst is useful for selective hydrogenation reduction of halogenated nitrobenzene to halogenated aniline (claimed). ADVANTAGE - The catalyst has higher efficiency and stronger stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing tungsten single-atom catalyst having graphene substrate comprising (i) adding tungsten metal precursor into the aqueous dispersion of graphene oxide and dispersing it evenly, (ii) adding ethylenediamine into the dispersion and mixing evenly, heating and reacting for a period of time to obtain graphene hydrogel, freeze-drying to obtain graphene aerogel, and (iii) pyrolyzing the graphene aerogel to obtain final product.