Performance of crosslinked sodium alginate/sulfonated graphene oxide as polymer electrolyte membrane in DMFC application: RSM optimization approach

Abstract

DMFC received great consideration since it was developed due to its efficiency in electricity production and easy start-up and process. The selectivity of sodium alginate-based membrane as a function of sulfonated graphene oxide and glycerol content is analysed using response surface methodology. It is observed that the properties of the membrane are strongly influenced by the glycerol and sulfonated graphene oxide loading in order to produce the optimum morphology and conducting properties, thus affecting the selectivity of the membrane and consequently the overall performance of the direct methanol fuel cell. The objective of this study is to determine the parameters that significantly affecting the performance of the membrane. Two parameters were taken into consideration that is the weight percentage of sulfonated graphene oxide and glycerol loadings. Both are determined approximately 0.5 wt% to 5 wt% and 0.5 ml–6.0 ml, respectively. The best selectivity result is achieved by using SA/SGO biomembrane with loadings of 2.78 wt% SGO and 3.11 ml of glycerol, respectively. The selectivity is determined as 12.956 × 104 S scm−3. This study proves that the sulfonated graphene oxide and glycerol improved the final membrane structures and performances of the membrane based on numerical analysis, the observation from field emission scanning electron microscopy, atomic force microscope structural analysis as well as the performance of direct methanol fuel cell.