Fabrication of Co3O4 pseudocapacitor electrodes from nanoscale cobalt-organic frameworks

Two nanoscale metal-organic frameworks (NMOFs), namely Co-Im and Co-Py, have been firstly prepared in poor solvent through a precipitation method. XRD, TGA and EA results show that as-synthesized NMOFs are isostructural with the reported crystal structure of {[Co(H2IDC)(2)(H2O)(2)]center dot 2DMF}(n) and {[Co(H2PDC)(PDC)]center dot 3H(2)O}(n) molecules. High temperature calcining of these Co-based NMOFs can result in pseudo-capacitive Co3O4 electrodes. Series of electrochemical measurements indicated that the as-prepared Co3O4 material could deliver a maximum specific capacitance of 233 F g(-1), good stability over 1500 cycles with the capacitance retention of 89.8% and low charge-transfer resistance of 1.22 Omega. (C) 2016 Elsevier Ltd. All rights reserved.