Energy-saving electrolytic γ-MnO(2) generation: non-noble metal electrocatalyst gas diffusion electrode as cathode in acid solution

γ-MnO(2), which is commercially used as an electrode material in batteries, is produced using large amounts of energy and leads to the production of high pollution as a secondary product. Ideally, this material should be fabricated by energy efficient, non-polluting methods at a reasonable cost. This study reports the green fabrication of γ-MnO(2) into a gas diffusion electrode with Pt-free catalysts in acid solution. Cobalt oxide nanoparticles were deposited on few-layer graphene sheets produced via a simple sintering and ultrasonic mixing method, leading to the fabrication of cobalt oxide/few-layer graphene. Co(3)O(4) nanoparticles are irregularly shaped and uniformly distributed on the surface of the few-layer graphene sheets. Characterization was conducted by X-ray diffraction, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy. Electrochemical characterization revealed the performance of cobalt oxide/few-layer graphene gas diffusion electrode in an electrolyte of 120 g L(−1) manganese sulfate + 30 g L(−1) sulfuric acid at 100 A m(−2) at 80 °C. The cobalt oxide/few-layer graphene gas diffusion electrode exhibited a lower cell voltage of 0.9 V and higher electric energy savings of approximately 50% compared with traditional cathodes (copper and carbon).