Performance of intrinsic heteroatoms in cobalt phosphide loaded ginkgo leave-based carbon material on promoting the electrocatalytic activity during hydrogen evolution reaction and oxygen evolution reaction

Abstract

Nitrogen (N) and sulfur (S) in ginkgo leaves are converted to carbon lattice heteroatoms, making them a matrix. Herein, cobalt phosphide (CoP) is loaded on the N/S/phosphorus (P) co-doped carbon matrix (CoP@NSPC) via the carbothermic reduction method using the ginkgo leave-based carbon as the precursor. The N/P co-doped carbon matrix loaded with CoP (CoP@NPC) are also prepared using glucose-based carbon as the support. Effects of intrinsic heteroatoms from ginkgo leaves are revealed through X-ray photoelectron spectroscopy (XPS) and ultraviolet photo-electron spectroscopy (UPS) compared with CoP@NPC. The N/S heteroatoms accelerate the electron transfer and adjust the d-band center of CoP@NSPC, thus causing a faster electrocatalytic process. The as-obtained CoP@NSPC exhibits excellent activity toward hydrogen evolution reaction (HER, 160 mV @ 10 mA cm−2) and oxygen evolution reaction (OER, 198 mV @ 10 mA cm−2). The assembly feasibility and catalytic performance are further verified in overall water splitting and exhibits high efficiency and long durability of CoP@NSPC.