ABSTRACT
The hybrid metal-organic frameworks (MOFs) with different Zn2+/Co2+ ratios are synthesized at room temperature with deionized water as the solvent. This use of deionized water can increase the yield of hybrid MOFs (up to 65-70%). After the pyrolysis, the obtained nanoporous carbons (NPCs) show a decrease in the surface area, in which the highest surface area is 655 m2 g-1. The as-prepared NPCs are subjected to activation with KOH in order to increase their surface area and convert cobalt nanoparticles (Co NPs) to Co oxides. These activated carbons are applied to electrical double-layer capacitors (EDLCs) and pseudocapacitors due to the presence of CoO and Co3O4 nanoparticles in the carbon framework, leading to significantly enhanced specific capacitance as compared to that of pristine NPCs. This synthetic method can be utilized in future research to enhance pseudocapacitance further while maintaining the maximum surface area of the carbon materials.
ABSTRACT
Metal-organic framework (MOF)-derived nanoporous carbon materials have attracted significant interest due to their advantages of controllable porosity, good thermal/chemical stability, high electrical conductivity, catalytic activity, easy modification with other elements and materials, etc. Thus, MOF-derived carbons have been used in numerous applications, such as environmental remediations, energy storage systems (i.e. batteries, supercapacitors), and catalysts. To date, many strategies have been developed to enhance the properties and performance of MOF-derived carbons. Herein, we introduce and summarize recent important approaches for advanced MOF-derived carbon structures with a focus on precursor control, heteroatom doping, shape/orientation control, and hybridization with other functional materials.
