A template-assisted strategy to synthesize a dilute CoNi alloy incorporated into ultramicroporous carbon for high performance supercapacitor application. Issue 14 (21st March 2019)

• Record Type: Journal Article
• Authors: Jiang, Yan; Wang, Yue; Zeng, Dehong; Wang, Yao; Ma, Yangde; Wang, Hai; Zhang, Xin; Dai, Xiaoping
• Is Part Of: Dalton transactions. Volume 48:Issue 14(2019)
• Page Start: 4702
• Page End: 4711
• Publication Date: 2019-03-21
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt00410f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Combination of metal alloy and porous carbon is a good strategy to prepare electrode material due to the contribution of both Faraday pseudocapacitors (FS) and electrical double-layer capacitors (EDLCs). Abstract : Carbon is widely studied as an electrical double-layer capacitor (EDLC) electrode material due to its high specific surface area and good electronic conductivity. However, the low capacitance and energy density limit its further commercial applications. Herein, we report a facile and novel synthesis of dilute CoNi alloy nanoparticles embedded into ultramicroporous carbon (CoNi/UMCs) via a template-assisted strategy using SBA-15 as a template. The CoNi alloy serves as not only the electron collector to decrease the conductivity during tests, but also creates CoNi oxide/oxhydroxide on the alloy surface in an alkali solution, promoting redox reactions in pseudocapacitors, enhancing the performance of supercapacitors. Interestingly, the final morphology of the composite is not transferred from SBA-15 and the ultramicropores absolutely come from sucrose itself. However, the presence of SBA-15 can definitely enlarge the surface area of the CoNi/UMCs. After carefully tailoring the loading of CoNi, we find that 0.95% CoNi/UMCs exhibit a high surface area of 613 m 2 g −1 with regular ultramicropores of 0.57 nm. Due to the synergistic effect of porous carbon and CoNi alloy, the unique 0.95% CoNi/UMCs exhibit a high specific capacitance of up to 268 F g −1 at 0.25 A g −1 in 6 M KOH aqueous solution and a high capacitance retention ratio of 97.8% after 10 000 cycles.