Synthesis of reduced graphene oxide/MnO2 nanocomposites for oxygen reduction reaction catalyst

Abstract

Lignin waste that comes from various biomass processing has caused an environmental problem which is undegradable under anaerobic condition. One way to use lignin waste is to utilize as an alternative carbon material precursor that applied for electrocatalyst on metal-air batteries. The purpose of this research was to convert Na-Lignin into carbon at carbonization temperature of 500, 700, and 900 °C then combined with MnO2 by soaking KMnO4 and carbon at 1:1 and 1:2 mass ratio. Na-Lignin carbonization produced r-GO (reduced Graphene oxide) particles with surface area and pore diameter of 261.584 m2/g and 3.82 nm at 700 °C. The best electrocatalytic performance was obtained from a composite sample of 1:2 mass ratio and a carbonization temperature of 900 °C, which had 3.39 electrons transfer for oxygen reduction reaction.