Facile Synthesis Polymeric Schiff Base Metal Complex as Electrode for High-performance Supercapacitors

This research presents a simple method for preparing poly Schiff base ligand (L) and its metal complex (M-L, M = Al3+, Cr3+, Zn2+) as electrode materials for supercapacitors, which is derived from mixing terephthalaldehyde, m-phenylenediamine and metal nitrate in ethanol at room temperature. Compared with L, M-L combine the advantages of larger surface area, appropriate mesopore diameter, unique morphology and suitable conductivity. The electrochemical properties of the materials are assessed by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) analysis in 6 M KOH electrolyte. The results show that the electrochemical performance of M-L significantly improve compared with L, especially when the current density is 0.5 A g(-1), Al-L displays a superior specific capacitance of 608.6 F g(-1). Moreover, the specific capacitance of Al-L still reaches 299.1 F g(-1) after 1000 GCD cycles at 10 A g(-1), which is higher than the initial capacitance of Cr-L and Zn-L. Moreover, the electrochemical resistance of Al-L is smaller than that of others. Therefore, Al-L will become an attractive material in supercapacitors, and opens the door for further research on various poly Schiff base metal complexes (poly[M(Schiff)]) as electrode materials for supercapacitors.