▎ 摘　　要

Rational design of low-cost and highly-efficient bifunctional oxygen electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is currently critical for renewable energy storage and conversion devices. Herein, we represent a series of three-dimensional porous B and N co-doped graphene aerogels (BN-GAs) using NH4B5O8 as precursor for B and N source by hydrothermal method and freeze-drying process. In this facile strategy, we can tune doping contents of B and N configurations in BN-GAs by simply changing the synthesis conditions. Linear sweep voltammetry results confirm that the increasing doping contents of pyridinic N and BC3 phases in BN-GAs can boost ORR activity, which may be because the enhanced synergy that arises from combining pyridinic N and BC3 phases can greatly improve ORR activity. The proposed BN-GAs not only show similar ORR activity to commercial Pt/C, but also more superior stability and excellent methanol tolerance than commercial Pt/C. Remarkably, the resultant BN-GAs also exhibit considerable OER activity and achieve desired performance as an air cathode for a rechargeable zinc-air battery device. Notably, this work may assist in a new insight to feasible preparation and molecular design of more advanced graphene-based catalyst, and can be extended to other catalytic system. (c) 2018 Elsevier Ltd. All rights reserved.