Cobalt and nitrogen co-doped hierarchically porous carbon nanostructure: a bifunctional electrocatalyst for oxygen reduction and evolution reactions

Abstract

We present a rational approach to the fabrication of Co and N co-doped porous hierarchical carbon nanosheet catalysts (CoNPCs). The CoNPCs exhibit excellent performance as an efficient non-precious metal electrode in alkaline fuel cell and Zn–air battery devices.

Cobalt/nitrogen codoped carbon nanosheets derived from catkins as a high performance non-noble metal electrocatalyst for oxygen reduction reaction and hydrogen evolution reaction

“…41,42 The electrochemical double-layer capacitance (C dl ) of Co/N-CNSs is calculated at 0.17 V vs. RHE from a series of CV curves with a scan rate from 10 to 140 mV s À1 . No faradaic reactions occurred in the range of the mentioned-above scan rates 40,41 and the electrochemical area of Co/N-CNSs is 5.67 mF cm À2 , as shown in Fig. 4d.…”

“…The durability and the stability of methanol induction are also two key concerns for the performance evaluation of electrocatalysts in fuel cells. 1,8,40 As shown in Fig. 3c, the chronoamperometric responses display only a slight activity loss of ca.…”

“…1,32 Such Co-N x coordination, which would generate a strong electronwithdrawing effect, could cause an electron density migration of adjacent C atoms. 19,40 Consequently, the migration is expected to effectively adsorb intermediates, which would enhance the ORR/HER kinetics. 4,19,40 The Co/N-catkin nanosheets were rst carbonized at 700, 800 and 900 C, respectively, for optimization of the electrocatalytic performance of Co/N-CNSs for comparison with that of commercial 20% Pt/C tested under the same conditions.…”

A Composite Bifunctional Oxygen Electrocatalyst for High‐Performance Rechargeable Zinc–Air Batteries

“…Tremendous efforts have been devoted to exploring bifunctional ORR/OER electrocatalysts including transition-metalcompounds, [24][25][26][27][28][29] metal-organic frameworks, [30][31][32][33][34][35][36][37] and heteroatomdoped nanocarbon. [38][39][40][41][42][43][44] Nevertheless, their bifunctionale lectrocatalytic performances remainu nsatisfactory with single active site. Actually,O RR and OER go through differentp ath-Rechargeable zinc-air batteries are considered as next-generation energy storage devices because of their ultrahigh theoretical energy density of 1086 Wh kg À1 (including oxygen) and inherents afety originating from the use of aqueous electrolyte.…”

“…Tremendous efforts have been devoted to exploring bifunctional ORR/OER electrocatalysts including transition‐metal compounds, metal–organic frameworks, and heteroatom‐doped nanocarbon . Nevertheless, their bifunctional electrocatalytic performances remain unsatisfactory with single active site.…”