Composite of coconut charcoal-based carbon/MnO₂ as metal-air battery electrocatalyst

Many types of research related to battery currently being developed to answer the increasing need for energy. One of the most exciting topics is about a metal-air battery that has low oxygen reduction reaction (ORR) in the cathode side as main problem. This research used a composite between MnO2 and carbon to increase the oxygen reduction reaction. MnO2 was synthesized from KMnO4 solution through electrochemistry method using multi-electrode at various temperatures. Carbon was synthesized from coconut charcoal through calcination and modified hummer method. Furthermore, The composite of MnO2/carbon was carried out using physical treatment. Sample analysis consists of characterization and electrocatalytic analysis. The characterization itself consists of morphological analysis using Scanning Electron Microscopy (SEM), and particle surface area analysis using Brunauer Emmet Teller (BET). While the electrocatalyst consists of Cyclic Voltammetry (CV) analysis to determine the occurrence of oxygen reduction reaction (ORR), and Linear Sweep Voltammetry (LSV) to determine the amount of electron transfer. According to the X-Ray Diffraction pattern and specific surface area, a higher temperature of potassium permanganate electrolysis indicated the lower performance of MnO2 produced. Also, after composited with carbon, the electrocatalytic analysis showed that both samples could initiate the oxygen reduction reaction with the number of electrons transferred are 1.52 for MnO2 30°C-Graphene and 2.28 for MnO2 60°C-Graphene which conclude that MnO2-carbon composite is quite promising to be researched further as electrocatalyst in the metal-air battery.