Boron-nitrogen-doped carbon dots on multi-walled carbon nanotubes for efficient electrocatalysis of oxygen reduction
Yanfei Pei1, Haoqiang Song2, Yuan Liu3
1College of Chemistry and Chemical Engineering, Henan Polytechnic University, No. 2001 Century Avenue, Jiaozuo City 454000, China.
Abstract:
Cost-effective production of metal-free catalysts for the oxygen-reduction reaction (ORR), to supersede Pt-based catalysts, is challenging. Here, a three-dimensional nanocatalyst was prepared by compounding multi-wall carbon nanotubes (MWCNTs) with easily modified and doped carbon dots (CDs) as sources of B and N. The catalyst has high conductivity and a large specific surface area similar to the MWCNTs, allowing exposure of many CDs with rich edge active sites and enhancing electron transfer. The catalyst exhibits excellent ORR performance, with 0.92 V of Eonset vs reversible hydrogen electrode (RHE). The E1/2 value exhibits a reduction of 50 mV compared with that of Pt/C (0.85 V) with a limited current density of 5.95 mA cm-2. The enhanced catalytic performance is attributed to the synergy of pyridine N and BC3. This work describes a simple and economical strategy for metal-free catalysts, and promotes the development of such catalysts for metal-air batteries and fuel cells.
