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]·2DMF}n and {[Co(H2PDC)(PDC)]·3H2O}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 Ω.

Graphical abstractCo3O4 nanoparticles are synthesized from annealing Co-based NMOFs and display pesudocapacitance behaviors, which can further be evaluated and confirmed by series of electrochemical measurements.Figure optionsDownload full-size imageDownload as PowerPoint slide