ZIF-8@MWCNT-derived carbon composite as electrode of high performance for supercapacitor

Carbon materials from zeolitic imidazolate framework (ZIF) present poor electrochemical performance as electrode materials for supercapacitors. In this work, well-intergrown ZIF nanocystals are strung on MWCNTs to form necklace architecture. After carbonization and chemical etching, porous carbons with necklace architecture and proper hierarchical micro-mesoporous structure were obtained. It exhibits excellent electrochemical performance as electrode material for supercapacitor in 1 M H₂SO₄ solution such as high specific capacitance up to 326 F·g⁻¹ at 1 A·g⁻¹, good rate capability and excellent cycling stability of 99.7% capacitance retention after 10000 cycles. The main reasons are due to the increased surface area, the improved electrical conductivity, and the combination of micro- and meso-porous structure. This provides another promising way to design porous carbons from ZIF materials for supercapacitors.