Conductive Bismuth-Catecholate Metal–Organic Frameworks Grown on Ti3C2T x Nanosheets for High-Performance Supercapacitors

• Published in: ACS applied nano materials Vol. 7; no. 12; pp. 14310 - 14320
• Main Authors: Chen, Si, Zhang, Haoliang, Liu, Yong, Guo, Jiacheng, Li, Xu, Zhang, Mingyi, Zhang, Dongwei, Fang, Pengfei, He, Chunqing
• Format: Journal Article
• Language: English
• Published: American Chemical Society 28.06.2024
• Subjects: 2D Ti3C2T x nanosheets; Ti3C2T x /Bi(HHTP) composite; conductive MOFs; supercapacitors; battery-type capacitance
• ISSN: 2574-0970; 2574-0970
• DOI: 10.1021/acsanm.4c01637

Ti3C2T x , as a member of the two-dimensional (2D) MXene family, is subject to severe self-restacking due to van der Waals forces between the surfaces of the nanosheets, which limits its application in supercapacitors. In addition, Ti3C2T x always stores electrical energy non-Faradaic, resulting in a low specific capacitance about 100 F g–1 in basic electrolytes. In this work, we report conductive bismuth-catecholate metal–organic frameworks (Bi­(HHTP)) with one-dimensional (1D) channels grown on the surfaces of 2D Ti3C2T x nanosheets (Ti3C2T x /Bi­(HHTP)) for supercapacitors. In the hybrid structure, conductive Bi­(HHTP) serves not only as the spacers to relieve the self-stacking of Ti3C2T x nanosheets but also as the active component to provide battery-type capacitance. Meanwhile, Ti3C2T x nanosheets provide skeletons for the conductive Bi­(HHTP), further enhancing the overall specific capacitance of Ti3C2T x /Bi­(HHTP). By taking advantage of appropriate porosity, redox activity, and good properties of charge transport of Bi­(HHTP), the specific capacitance of Ti3C2T x nanosheets is significantly increased. The Ti3C2T x /Bi­(HHTP) electrode obtained exhibits an impressive specific capacitance of 326 F g–1 at 0.5 A g–1 and a good rate capacity of 52%. Additionally, an asymmetric device is assembled with a Ni­(OH)2 cathode and a Ti3C2T x /Bi­(HHTP) anode, demonstrating remarkable performance with a maximum specific energy of 22.3 Wh kg–1 and a maximum specific power of 11.2 kW kg–1. This work presents a promising strategy for developing high-performance supercapacitor electrodes based on Ti3C2T x , offering potential avenues for enhancing performance in energy storage applications.