To begin, prepare the copper THQ/CB/PVDF electrode by dissolving 10 milligrams of PVDF in 1.4 milliliters of NMP. Disperse 50 milligrams of pre-synthesized copper THQ MOF followed by 40 milligrams of carbon black in the solution and leave it to stir vigorously overnight. Coat the homogenous slurry onto an aluminum disc of 15 millimeter diameter and approximately 9.7 milligrams mass.
Next, assemble the lithium copper THQ coin cells from the bottom to the top, starting with a negative shell, a 0.5-millimeter spacer, lithium, a separator, the prepared copper THQ electrode, a spacer, a spring, and a positive shell. Add a drop of 0.04 milliliters of electrolyte before and after placing the separator. To prepare the electrochemical intermediates, use a homemade device to compress the coin cell by tightening the screw.
Then, connect the device to the measuring cables in the glove box. Next, connect the instrument outside the glove box to the ports corresponding to the coin cell. Finally, perform cyclic voltammetry and galvanostatic charge or discharge measurements to obtain the intermediates at various potentials.
After electrochemical cycling, carefully disassemble the coin cell to avoid short circuits. Rinse the cycled copper THQ electrode with five milliliters of battery-grade dimethyl carbonate and dry it for 30 minutes at room temperature. Using a clean spatula, transfer the sample from the aluminum disc to aluminum foil.
Transfer the sample powder into a sample tube and seal it tightly with a cap and transparent film or with a vacuum until further use. Electrochemical performances of the lithium copper THQ batteries demonstrated that the carbon and binder did not affect the electron transfer, and the battery delivered with a specific capacity of 390 milliampere-hours per gram in the first discharge process. Differential capacity analysis of copper THQ/CB/PVDF electrode demonstrated three electronic states, namely copper state, pi-d conjugated state, and delocalized pi-electron state account for the three redox peaks, and cyclic voltammetry curves varied from 4.0 to 1.5 volts.
