Microwave and Solvent Exchange Co-Activated Ni-MOFs Anode Materials Achieving Assisted Reaction Kinetics in...

A planar layered MOF material, PTCDA-Ni, is prepared through a coordination reaction of PTCDA (3,4,9,10-perylenetetracarboxylic acid) with Ni ions, and the PTCDA-Ni is activated by solvent exchange activation with trichloromethane (TCM), acetone (AC), and co-activation with AC and microwaves (AC&Mw) to obtain three MOFs materials (PTCDA-Ni@TCM, PTCDA-Ni@AC, PTCDA-Ni@AC&Mw). The results show that the activated PTCDA-Ni has a different degree of enhancement in the specific surface area, the size of the pore size, and its stacking aggregation compared with the unactivated PTCDA-Ni. Meanwhile, the activation strategy can reduce the content of guest molecules in the pore structure, exposing more active sites and then improving the electrochemical properties. As a result, the capacity retention of PTCDA-Ni electrode before activation is 60.8% after 200 cycles at a current density of 0.1 A·g^-1, while under the same conditions, the capacity retention of PTCDA-Ni@TCM, PTCDA-Ni@AC, and PTCDA-Ni@AC&Mw electrodes are significantly improved to 92.1%, 96.9%, and 96.9%, respectively. The results of the GITT test and the CV curves at different scanning speeds similarly show that the activation strategy can increase the migration rate of lithium ions and further improve its electrochemical performance, which will open up a new idea for the design of anode materials for high-performance LIBs.