Cobalt intercalated redox active 1,2,4,5-benzene-tetra-carboxylic acid-pyridine-3,5-dicarboxylic acid bi-linker organic framework for state-of-the-art battery-supercapacitor hybrids

Abstract

Batteries and supercapacitors as congener of energy storage devices, their hybrids hold within itself great capability and grab broad interest. There are many contender electrode materials for hybrid supercapacitors, however, emerging from a unique class of porous materials, metal-organic-frameworks bear distinctive properties which make them favorable to be integrated in energy storage devices. Herein, we have designed bi-linker cobalt MOF by making cobalt ion captured by two different organic ligands i.e. pyridine-3,5-dicarboxylic acid and 1,2,4,5-benzene-tetra-carboxylic acid. The synthesized MOF has a novel structure and to the best of our knowledge not reported before in any study. Bi-linker Co-MOF (Co–B–H-MOF) was structurally, morphologically and electrochemically characterized, and applied specifically to hybrid supercapacitors. The electrochemical capabilities of the Co–B–H-MOF were investigated in three electrode assembly and for practical implementations a hybrid supercapacitor was fabricated by amalgamating Co–B–H-MOF and activated carbon in a single device. Moreover, a theoretical approach was implied using Dunn's model to extract out the regression parameters and capacitive-diffusive contributions of the hybrid supercapacitor.