An Advanced Nitrogen‐Doped Graphene/Cobalt‐Embedded Porous Carbon Polyhedron Hybrid for Efficient Catalysis of Oxygen Reduction and Water Splitting

Abstract

A novel hybrid electrocatalyst consisting of nitrogen‐doped graphene/cobalt‐embedded porous carbon polyhedron (N/Co‐doped PCP//NRGO) is prepared through simple pyrolysis of graphene oxide‐supported cobalt‐based zeolitic imidazolate‐frameworks. Remarkable features of the porous carbon structure, N/Co‐doping effect, introduction of NRGO, and good contact between N/Co‐doped PCP and NRGO result in a high catalytic efficiency. The hybrid shows excellent electrocatalytic activities and kinetics for oxygen reduction reaction in basic media, which compares favorably with those of the Pt/C catalyst, together with superior durability, a four‐electron pathway, and excellent methanol tolerance. The hybrid also exhibits superior performance for hydrogen evolution reaction, offering a low onset overpotential of 58 mV and a stable current density of 10 mA cm−2 at 229 mV in acid media, as well as good catalytic performance for oxygen evolution reaction (a small overpotential of 1.66 V for 10 mA cm−2 current density). The dual‐active‐site mechanism originating from synergic effects between N/Co‐doped PCP and NRGO is responsible for the excellent performance of the hybrid. This development offers an attractive catalyst material for large‐scale fuel cells and water splitting technologies.

Carbon skeleton doped with Co, N, S and P as efficient electrocatalyst for oxygen evolution reaction

“…5b) demonstrates the superior catalytic activity and efficient electron/mass transfer in CoCN@PZS-450°C. The performance of CoCN@PZS-450°C is better than those reported recently under the same conditions [44,45] and comparable to those performed in 0.1 mol L −1 KOH aqueous solutions [46][47][48][49] (Table 1). Moreover, a very small decay of the current density after continuous CV scanning for 1,000 cycles demonstrates very good electrochemical stability, partially ascribed to the presence of an outer C-rich protecting layer.…”

Non-Precious Electrocatalysts for Oxygen Reduction Reaction in Alkaline Media: Latest Achievements on Novel Carbon Materials

“…Its excellent activity was mainly attributed to the following factors: (i) the doping effect of N and Co; (ii) the porous structure; and (iii) the good contact between N/Co-doped carbon polyhedron and nitrogen-doped reduced graphene oxide. [58], [53], [55], [56], [49], [47], [50], [51], [59], [54], [57], [48], [52]). [58], [53], [55], [56], [49], [47], [50], [51], [59], [54], [57], [48], [52]).…”

“…A novel hybrid electrocatalyst with reduced nitrogen-doped graphene/cobalt embedded porous carbon polyhedron was developed by Hou et al [53]. A four-electron pathway was activated, performing E1/2 = 0.93 V vs. RHE.…”

Bimetallic organic frameworks derived CuNi/carbon nanocomposites as efficient electrocatalysts for oxygen reduction reaction

“…A lack of highly active but low-cost electrocatalysts of oxygen reduction reaction (ORR) is one of the major bottlenecks for the progress in such energy systems [2][3][4]. Presently, Pt-based materials are the best-known ORR catalysts because of their high efficiency, but are limited to a great extent by their prohibitive cost and low stability [4][5][6]. In this regard, a broad range of abundant and less expensive materials, including non-precious metals and metal-free materials, have been actively explored as catalysts for oxygen reduction [7][8][9].…”