Direct Synthesis of Phosphorus-Doped Mesoporous Carbon Materials for Efficient Electrocatalytic Oxygen Reduction

Abstract

Chemical doping has been recognized as a promising route to achieve novel physicochemical functions of porous carbons as metal-free catalysts in renewable energy-related technologies, such as electrochemical oxygen reduction reaction (ORR). However, it remains challenging to exploit an effective method for the synthesis of metal-free carbonaceous electrocatalysts. Herein, we report the direct synthesis of phosphorus-doped mesoporous carbonaceous electrocatalysts for the first time through softlating method, in which organophosphonic acid serves as the phosphorus source. The resulting mesoporous carbon material possesses high doping level, large surface area, and an interconnected mesopore system, ensuring the sufficient exposure and availability of catalytic sites to realize considerable catalytic activity for ORR in alkaline media. More importantly, much better tolerance for methanol oxidation, higher durability, and comparable Tafel slopes as compared with the commercial Pt/carbon (Pt/C) catalyst are valuable for developing alternative fuel cells and metal-air batteries. Novel carbon: P-doped metal-free mesostructured carbocatalysts with high surface area are synthesized through a softlating strategy with organophosphonic acid as the P source. The catalysts are efficient for the oxygen reduction reaction (ORR) with favorable kinetics, strong durability, and excellent methanol tolerance.