Ni-Based Composites from Chitosan Biopolymer a One-Step Synthesis for Oxygen Evolution Reaction

Abstract

Cost-efficient and sustainable electrocatalysts for oxygen evolution reaction (OER) is highly desired in the search for clean and renewable energy sources. In this study, we develop a new one-step synthesis strategy of novel composites based on Ni and molybdenum carbide embedded in N- and P-dual doped carbon matrices using mainly chitosan biopolymer as the carbon and nitrogen source, and molybdophosphoric acid (HMoP) as the P and Mo precursor. Two composites have been investigated through annealing a mixture of Ni/chitosan and HMoP with two unlike carbon matrices, melamine and graphene oxide, at a high temperature. Both composites exhibit similar multi-active sites with high electrocatalytic activity for OER in an alkaline medium, which is comparable to the IrO2 catalyst. For this study, an accurate measurement of the onset potential for O2 evolution has been used by means of a rotating ring-disk electrode (RRDE). The use of this method allows confirming a better stability in the chitosan/graphene composite. This work serves as a promising approach for the conversion of feedstock and renewable chitosan into desired OER catalysts.

Non-precious Melamine/Chitosan Composites for the Oxygen Reduction Reaction: Effect of the Transition Metal

“…The preparation of the composites follows the synthetic strategy developed by our research group (Aghabarari et al, 2019) and is schematically illustrated in Figure 1. For the synthesis of composites, an appropriate amount of the chloride salt precursor (Sigma-Alderich Company) of Co, Fe, or Cu (20 wt % with respect to the composite melamine/chitosan) was dissolved in water and then was added to a solution of chitosan in acetic acid solution.…”

“…Herein, we have synthetized Me/Mo 2 C (Me Fe, Co, Cu)based composites embedded in N-and P-dual doped carbon using a facile synthesis strategy developed by our research group (Aghabarari et al, 2019). For this preparation, the corresponding metallic precursor and molybdophosphoric acid (HMoP) are pyrolyzed together with the mixture chitosan/melamine as carbon and nitrogen sources.…”