A facile morphology tunable strategy of Zn-MOF derived hierarchically carbon materials with enhanced supercapacitive performance through the solvent effect

Metal-organic framework (MOF) derived porous carbon materials have been widely applied as active materials for supercapacitors due to their large specific surface area and ordered pore structure. This paper presents a facile and effective strategy to regulate the morphology of a zinc-based metal-organic framework (Zn-trimesic acid, Zn-BTC) by adjusting the ethanol content in a solvent, which can effectively change the pore structure of Zn-BTC derived porous carbon (PC). The optimal PC prepared in 50% ethanol displays a rodlike structure with a large specific surface area (SSA) of 1930 m(2) g(-1) and an average pore size of 2.9 nm. This material shows an excellent rate performance with 78.8% capacitance retention when the current density increases from 1 A g(-1) to 100 A g(-1) and outstanding electrochemical stability with only 2.2% decline of capacitance after 200 000 cycles at 50 A g(-1). Moreover, the assembled symmetrical capacitor shows a high energy density of 16.09 W h kg(-1) at 698 W kg(-1) and 11.89 W h kg(-1) at a high power density of 41.56 kW kg(-1). This method would provide a new pathway for the preparation of carbon materials with an adjustable pore size for high-performance supercapacitors.

Automated summary

This paper presents a facile and effective strategy to regulate the morphology of a zinc-based metal-organic framework (Zn-BTC) by adjusting the ethanol content in a solvent, which can effectively change the pore structure of Zn-BTC derived porous carbon (PC). The optimal PC prepared in 50% ethanol displays a rodlike structure with a large specific surface area (SSA) and excellent electrochemical stability. This method provides a new pathway for the preparation of carbon materials with an adjustable pore size for high-performance supercapacitors.