Preparation and investigation of carbon-based electrocatalysts from different parts of biomass for oxygen reduction reaction

Carbon-based oxygen reduction catalysts are widely used in catalyzing the oxygen reduction reaction (ORR) due to their low cost, good electrical conductivity, controllable pore structure and good electrochemical stability. In this paper, carbon materials were prepared from different parts of biomass (leaves and stems) through one-step pyrolysis method. The performance of the obtained catalysts was analyzed by X-ray diffraction (XRD), Raman, X-ray Photoelectron Spectroscopy (XPS) and Linear Sweep Voltammetry (LSV). The results demonstrate that compared with the stem carbon, the leaf carbon contains high contents of P, S and N, especially quaternary-N and pyridinic-N, which are responsible for the high performance in the ORR with onset potentials of 0.529, 0.215 and −0.046 V (vs. SCE) in wide ranges of pH (acid, alkali and neutral solutions, respectively). This indicates that biomass based carbon material especially leaf based shows a great application potential for catalyzing ORR in fuel cells.