▎ 摘　　要

Nitrogen- and metal-atom-doped graphene are very promising electrocatalysts for many renewable energy conversionreactions such as oxygen reduction/evolution reactions (ORR/OER).To maximize the bifunctional or multifunctional catalytic performance,increasing the doping amount of both nonmetal nitrogen and metals onlarge-surface-area free-standing 3D porous graphene is very desirable.Herein, we design and prepare 3D bicontinuous nitrogen and noble-metal single atoms/clusters-doped small-pore-size nanoporous grapheneby a CVD process using a designed 12-component ultrahigh-entropynanoporous alloy template, which has greatly inhibited surface diffusioneven under high temperatures of 800-1000 degrees Cbecauseoftheincorporation of a suitable amount of high-melting-point metals. Witha small-pore size of similar to 16.7 nm and a high curvature, the 3D nanoporousgraphene is able to host/stabilize a high amount of N (5.88 at. %) and metal single atoms/clusters (Au, Pt, and Ir), which arein situ anchored on graphene during the removal of the nanoporous template. As a result, the obtained 3D graphene-basedcomposite exhibits excellent electrocatalytic activities toward both ORR and OER in both alkaline and acidic media. This workdemonstrates a scalable and economic route to prepare metal- and nonmetal-codoped 3D graphene with ultrasmall porosity for different electrochemical applications.