Investigation of Pd Based Metal-Carbon As Bifunctional Electrocatalyst for OER and ORR

Abstract

Developing oxygen reduction/ evolution reaction (ORR/OER) bifunctional electrocatalysts has great significance for promoting the sustainable energy conversion. Herein, Pd (5wt% only) based bimetallic catalyst adhered well on heteroatom doped conducting carbon substrate is designed and constructed. Rich defects, multiple active centers and strong synergistic effect with rapid ion/electron transport ability allow the electrocatalyst to exhibit superior performance (Li et al., 2019). Owing to its more active metal-Pd sites due to high surface area conducting carbon matrix an ultralow overpotential of 240 mV at 10 mA/cm2 for OER was obtained. It outperforms state of art RuO2 and Pt/C electrocatalyst. High half-wave potential (E1/2) of 0.821 V for ORR is comparable to commercial Pt/C (E1/2 =0.819 V) electrocatalysts was attained. The catalyst exhibits a prolonged stability in alkaline medium at 20 mA cm-2 for 24 h for OER and a small 20 mV shift in linear sweep voltammetry scan after accelerated durability test for 5000 cycles at 50mV/s for ORR. In-situ Raman analysis exhibits surface oxidation of electrocatalyst on OER in highly alkaline (1M KOH) conditions.Reference:Li, S., Hao, X., Abudula, A., & Guan, G. (2019). Nanostructured Co-based bifunctional electrocatalysts for energy conversion and storage: current status and perspectives. Journal of Materials Chemistry A, 7(32), 18674–18707. https://doi.org/10.1039/C9TA04949E