Highly enhanced proton conductivity of single-step-functionalized graphene oxide/nafion electrolyte membrane towards improved hydrogen fuel cell performance

Abstract

Acidic group functionalized graphene oxide (GO) as a filler to the state-of-art Nafion electrolytes are regarded as potential materials towards next-generation fuel cell application. However, the tedious synthesis process for GO functionalization, and aggravated chemical durability at high temperatures demands the scientific community to design suitable Nafion-based functionalized GO electrolytes with superior proton conductivity and power density at actual fuel cell conditions i.e., 80 °C and 100% relative humidity (RH). Herein, a potential single-step-phosphorylated graphene oxide (sPGO) modified Nafion (sPGO/NF) is introduced to simultaneously multifold the proton conductivity, chemical durability, and power density of Nafion. Under actual fuel cell conditions, the sPGO/NF exhibits maximum proton conductivity (0.306 Scm−1) which is 1.7-fold and 1.6-fold higher than that of rNF and GO/NF, respectively. Moreover, sPGO/NF achieves the maximum power density of 0.652 Wcm−2 (80 °C, 100% RH), much higher than the rNF (0.51 Wcm−2) and GO/NF (0.53 Wcm−2) at same condition.