Preparation of Co–N carbon nanosheet oxygen electrode catalyst by controlled crystallization of cobalt salt precursors for all-solid-state Al–air battery

Abstract

Production of bifunctional catalysts for catalyzing both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly advisable but challenging with respect to the applications of these catalysts in renewable energy conversion and storage technologies. Herein, we prepared highly reactive and stable cobalt-embedded nitrogen-rich carbon nanosheets (Co-N/CNs). Based on density functional theory (DFT) calculations and experiments, the as-prepared Co-N/CNs showed outstanding catalytic activities toward both OER and ORR. The optimized Co-N/CNs-800 catalyst revealed outstanding bifunctional catalytic activities for both ORR and OER with high catalytic efficiency and long-term durability, which were even comparable with those of the state-of-the-art Pt/C and RuO 2 catalysts. Furthermore, we observed that different cobalt salt precursors affected the size of Co nanoparticles, and both ORR and OER catalytic activities displayed completely consistent variations (sulfate < acetate < chloride < nitrate). An all-solid-state Al-air battery device comprising this hybrid catalyst showed superior performance when compared with the device containing the Pt/C catalyst.

A Mechanistic Overview of the Current Status and Future Challenges in Air Cathode for Aluminum Air Batteries

“…The author employed several precursors to create the ideal NP size for ORR due to the inverse relationship between the solubilities of Co salt and the size of nano Co. Co salts experienced nucleation and growth on carbon sheets using water vaporization before being reduced and coated in carbon following high-temperature calcination. [82] In another report, Liu and co-workers [83] uniformly dispersed CoNPs in integral three dimensional spiral-like polyhedron (SP) N-doped porous carbon, which boosted mass/electrons transport process at the three-phase interface of the oxygen reaction. This was accomplished by creating generous bifunctional active sites (such as CoÀ N x , CoÀ O, and defects sites) with high specific surface area and large pore volume through gas foaming.…”

Recent Progress on the Synthesis and Modified Strategies of Zeolitic‐Imidazole Framework‐67 Towards Electrocatalytic Oxygen Evolution Reaction

“…The uniform structure of cobalt species with imidazole linker provides an abundant porous structure with unique properties on ZIF‐67. Considering the OER mechanism on the ZIF‐67 catalyst, in‐situ techniques were performed to investigate the structural transformation and evaluate active mechanistic sites (intermediate species) during the reaction of OER [24–27] . The Co–Nx coordination in the structure of ZIF‐67 was hydrolyzed and converted into Co–Ox species (Co–O, Co–OH, CoOOH) as the intermediate species under the electrolyze solution (alkaline condition).…”

“…Considering the OER mechanism on the ZIF-67 catalyst, in-situ techniques were performed to investigate the structural transformation and evaluate active mechanistic sites (intermediate species) during the reaction of OER. [24][25][26][27] The Co-Nx coordination in the structure of ZIF-67 was hydrolyzed and converted into Co-Ox species (Co-O, Co-OH, CoOOH) as the intermediate species under the electrolyze solution (alkaline condition). Notable, the transformation of Co-Ox mainly occurred on the surface of the ZIF-67 catalyst.…”

Electrospun Al2O3 Film as Inhibiting Corrosion Interlayer of Anode for Solid Aluminum–Air Batteries

“…In addition, the safety issues of LIBs, such as thermal runaway, pose ongoing challenges for their application in personal electronics [9]. Solid metal-air batteries (including Zn [10,11], Al [12][13][14], Fe [15] and Li [16]) have been widely agreed upon as a next-generation energy storage system owing to their light weight, high safety and environmental friendliness [17]. Solid metal-air batteries generally use alkaline gel electrolyte instead of traditional liquid alkaline electrolyte [18][19][20][21].…”