Preparation of p-phenylenediamine acetaldehyde-metal ion complexes and its electrochemical properties

Abstract

The development of electrochemical energy storage is of great significance to "carbon peak" and "carbon neutrality". As a key research direction of electrochemical energy storage, supercapacitors are widely used in transportation information, industrial manufacturing, intelligent equipment and other fields with high power density, long cycle life and good safety The objective of this paper is to prepare p-phenylenediamine acetaldehyde is also known as Schiff base B. From there, we introduced metal ionic complexes (M=Al^3 +, Co²⁺, Cu²⁺) to prepare p-phenylenediamine glycolaldehyde-metal ionic complexes (Schiff base B-M,M=Al³⁺, Co²⁺, Cu²⁺). The Schiff base B-M polymer exhibited a finer structure and a higher specific surface area when compared to Schiff base B-M. Additionally, the Schiff base B's spherical structure was destroyed, exposing more of the electrode material's active sites. This led to the formation of richer ion channels between the electrolyte ions in the electrolyte and the electrode material, ultimately improving the capacitive performance. Cyclic voltammetry (CV), constant current charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) were used to assess the electrochemical performance of Schiff base B-M. The findings demonstrated a significant increase in the specific capacitance of the Schiff base B-M electrode material when compared to the Schiff base B electrode material, suggesting that the doping of metal ions can raise the specific capacitance of poly-Schiff bases. The Schiff base B-Cu electrode material had the best multiplicative performance, with a specific capacitance of 52 F/g at 10 A/g and a multiplicative performance of 50.2 %, while the Schiff base B-Co had a specific capacitance of 38 F/g with a multiplicative performance of Schiff base B-Cu had a specific capacitance of 52 F/g at 10 A/g with a multiplicative performance of 50.2 %, while Schiff base B-Co had a multiplicative performance of 38 F/g with a multiplicative performance of 28.5 %, and Schiff base B-Al had a multiplicative performance of 28 F/g with a multiplicative performance of 23.3 % only. Because of this, Schiff base B-M would be a potential material for supercapacitors and provided an avenue for more study into different poly-Schiff alkali metal complexes as supercapacitor electrode materials.