Fast and scale-up synthesis of amorphous C,N co-doped mesoporous Co-based phosphates as advanced electrodes for supercapacitors and water oxidation

• Published in: Sustainable energy & fuels 2021-11, Vol.5 (22), p.5741-5747
• Main Authors: Guo, Zheng-Han, Lin, Jie-Ying, Chen, Pei-Ru, Ou, Kai-Qin, Xu, Xiang-Ya, Li, Jin-Kun, Huang, Sai, Sang, Xin-Xin, Liu, Jing-Cheng, Song, Jun-Ling
• Format: Article
• Language: English
• Subjects: Capacitance; Cobalt; Decomposition; Electrochemistry; Electrode materials; Electrodes; Energy conversion; Energy storage; Industrial applications; Oxidation; Oxygen evolution reactions; Phosphates; Precursors; Supercapacitors
• ISSN: 2398-4902; 2398-4902
• DOI: 10.1039/d1se01313k

Convenient and green methods to synthesize highly efficient and stable multi-functional electrode materials are the key and a challenge for the industrial application of new energy conversion devices. Herein, we have developed a general host-guest strategy to construct amorphous hetero-atom doped cobalt phosphates; in the first step, we fast synthesized large-scale 2D Co-based phosphate precursors with different organic amine guest molecules by a hydrothermal method, afterwards, we calcined these precursors at different annealing temperatures, leading to the decomposition of organic guest molecules, and consequently, we obtained amorphous C,N co-doped mesoporous Co-based phosphates during this decomposition process. Moreover, the optimal C4NCPO-450 shows bi-functional activity for the Oxygen Evolution Reaction (OER) and supercapacitor applications. Which has a low overpotential of 292 mV and a Tafel slope of 67.45 mV dec −1 for the OER, and when used as an electrode material for supercapacitors, it reveals a large specific capacitance of 326 F g −1 @1 A g −1 , accompanied by a stability of 2200 charge and discharge cycles. We suppose that this method can be used to prepare other hetero-atom doped mesoporous electrode materials, which should be promising candidates in the electrochemical energy storage and conversion field. Convenient and green methods to synthesize highly efficient and stable multi-functional electrode materials are the key and a challenge for the industrial application of new energy conversion devices.