Synthesis of bimetallic CoNi-CoNiO2 nanoparticles embedded into mesoporous carbon as high-performance catalysts for supercapacitor electrode

• Published in: Microporous and mesoporous materials 2018-12, Vol.272, p.222-231
• Main Authors: Jiang, Yan, Wang, Yue, Zeng, Dehong, Xiao, Yun, Wang, Hai, Zhang, Xin, Dai, Xiaoping
• Format: Article
• Language: English
• Subjects: Bimetallic CoNi-CoNiO2 nanoparticle; High-performance supercapacitor; Mesporous carbon; Synergistic effect
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2018.06.031

Controlled integration of metal oxide/carbon structures for clean energy storage and conversion has drawn much attention in recent years. However, designing the metal oxide/carbon with high conductivity and good cycle durability still remains a challenge. Herein, we demonstrate a facile synthesis of bimetallic CoNi-CoNiO2 nanoparticles embedded into mesoporous carbon as electrode material (CoNi-CoNiO2-CMK-3) for supercapacitor. The mesoporous silica is used as the template, Ni(NO3)2 and Co(NO3)2 as the Ni2+ and Co2+ precursor, and sucrose as the carbon source. The molar ratio of Co2+ (Ni2+)/sucrose and pyrolysis temperatures are carefully screened. Combining the advantages of mesoporous carbon and the uniformly distributed CoNi-CoNiO2 particles, the composites exhibit well-defined capacitive features. Especially, the sample with 0.008 molar ratio of Co2+/sucrose and pyrolyzed at 800 °C display the highest capacitance up to 280 F g-1 at 0.25 A g−1 in 6 M KOH aqueous solution. In addition, 97.7% of the original capacitance is obtained after 10000 cycles. The high performance should be due to the fast ion-transport through mesoporous carbon and redox reaction on CoNi-CoNiO2 particles. [Display omitted] •A facile technique is used to prepare bimetallic CONi-CoNiO2 nanoparticles incorporated into mesoporous carbon.•The hybrid electrodes combine the advantages of pseudocapacitors and double-layer capacitors elegantly.•The strong interaction between Co and Ni species enhances the electrical performance significantly.•Good capacitance of 280 F g−1 and outstanding cycling stability up to 10000 cycles are obtained.