Investigations on electrochemical performance of Ni Co Ni CoMOFs and their composites with FMWCNTs for hybrid supercapacitors

Abstract

The urgent need to investigate energy production from alternative energy sources is driven by a sharp increase in per capita energy demand and the depletion of non-renewable energy sources. It is a crucial time to switch from non-renewable to renewable energy sources to achieve sustainable energy production. Henceforth, clean energy production from solar, wind, and tidal energy sources is a prominent concern for the research community. Energy production and storage are two vital parts of energy management. Eventually, highlighting the importance of developing efficient energy storage technologies is as equally significant as finding novel energy resources. Undoubtedly, it is an important task to develop advanced energy storage systems. newlineSupercapacitors are one of the fascinating and emerging energy storage devices and they exceed specific energy and specific power than electrolytic capacitors and batteries\fuel cells respectively. This doctoral work mainly aims on the development of competent electrode materials for supercapacitors. Recently, Metal Organic Frameworks (MOFs) are emerged as a new class of porous materials which have gained immense research attention in the field of supercapacitors. In this research work, Ni and Co based MOFs and their nanocomposites were synthesized for high performance hybrid supercapacitors. Initially, Ni-MOFs and Co-MOFs were synthesized via solvothermal method and investigated their electrochemical performances. Later, Ni/Co-MOFs were prepared by changing Ni and Co precursor molar ratios and the change in Ni and Co molar ratios in MOFs results three different morphologies such as ultra-thin nanoflakes, dandelion-like and nanospike structures. The effect of physico-chemical properties on supercapacitance performances also studied in detail. Ni/Co-MOFs with 1:1 ratio of Ni and Co demonstrated a high supercapacitance performance with 576 C/g at current density of 2.5 A/g and cycles stability of 86%. newlineThe poor intrinsic properties of Ni/Co-MOFs were reduced by doping F-MWCNTs in the