Synthesis, Characterization and Electrochemical studies of Zeolitic Imidazolate Frameworks (ZIFs) Derived Nanoporous Carbon Based Materials

Abstract

For many past years, metal oraganic frameworks (MOFs) have been promising candidate for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) due to their high surface area, good porosity and tuneable properties. The benchmark catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are Pt/C and IrO2 but their high cost, low stability and scarcity has limited their applications. One of the drawback of MOFs is that they have poor conductivity due to presence of organic ligands. In order to overcome the conductivity problem, composite of ZIF (subclass of MOF) is made with GO in the present work. The simple and clean mixing method (sonication and stirring) was used to synthesize zeolitic imidazolate framework (ZIF-67 and ZIF-8), their composite with GO followed by their carbonization in tube furnace. Nanoporous carbon based materials have good electrical conductivity, high surface area and they exhibit excellent chemical and mechanical stability. The synthesized materials are characterized by XRD, IR, TGA and BET,SEM and EDX. XRD confirms the phase purity and crystallinity, IR confirms the presence of functional group. TGA gives information about thermal stability of materials and BET tells about the surface area. Electrochemical studies of synthesized material were done by using linear sweep voltammetry (LSV), Electrochemical impedence spectroscopy (EIS) and Tafel slope.