▎ 摘　　要

Based on a swelling-filling modification strategy, sheared graphene oxide (SGO) sheets are in-situ inserted into the Nafion membrane and act as bi-functional fillers to simultaneously improve the methanol-permeation resistivity and proton conductivity. Proton/methanol selectivity, as a key descriptor of overall performance of the proton exchange membrane, of the Nafion membrane is therefore 4-fold increased. At the same time, the mechanical, oxidative and thermal stabilities of the Nafion membrane are also improved by the SGO sheets due to the interaction between SGO and Nafion. As a result, the swelling-filling modified SGO - Nafion membrane is therefore considered as a promising electrolyte for direct methanol fuel cell (DMFC) application and the power of the Nafion based DMFC can be improved by ca. 50% during the polarization measurement. (C) 2018 Elsevier Ltd. All rights reserved.