▎ 摘　　要

N-doped graphene-based materials show excellent promise as metal-free electrocatalysts for the oxygen reduction reaction (ORR). Because the N-doped graphene-based materials contain significant amounts of N and O atoms, it is important to understand the correlation between the chemical environments of these atoms and the catalytic performance of the materials. In this work, we prepared ammonia-reduced graphene oxide (A-rG-O) using a solution process and a set of A-rG-O samples thermally treated at high temperatures (300-700 degrees C). The chemical structure and ORR performances of A-rG-O materials were investigated. (C) 2016 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.