Enhanced electrochemical properties of polypyrrole upon addition of acid-treated palygorskite templates

Polypyrrole/Palygorskite (PPy/Pal) nanocomposites were prepared by chemical oxidative polymerization method on Pal templates modified with two different acid treatments. The acid treatments were implemented on natural Pal to increase its specific surface area and porosity, but at the same time, maintaining its fibrillar morphology and crystalline structure. In this way, Pal was firstly treated in a 1 M HCl solution (designated as Pal1). This was next treated in a 5 M H2SO4 solution to obtain Pal2. Both Pal1 and Pal2 were characterized by X-ray diffraction, elemental analysis, scanning electron microscopy, and surface area analysis. The electrochemical properties of resulting PPy/Pal nanocomposites were evaluated through cyclic voltammetry, charge/discharge, and electrochemical impedance spectroscopy measurements to explore their potential as electrodes for electrochemical capacitors. The experimental results indicated that all PPy/Pal nanocomposites exhibited enhanced electrochemical properties compared with PPy. The maximum specific capacitance of the nanocomposites achieved 173 F g(-1) at 3 mA/cm(2), which was similar to 60% higher than that of PPy electrode (109 F g(-1)), and retained 96% of its initial capacitance after 3200 galvanostatic charge-discharge cycles. The above results suggests that both mild acid-treated Pals are good alternatives to be used as natural and low-cost hard templates for the production of one-dimensional PPy/Pal nanocomposites, which exhibited promising potential to be used as electrodes for electrochemical capacitors.

Automated summary

In this study, Polypyrrole/Palygorskite (PPy/Pal) nanocomposites were prepared using acid treatments on Pal templates, resulting in enhanced electrochemical properties compared to PPy alone. The acid-treated Pals showed potential as natural and low-cost templates for producing one-dimensional PPy/Pal nanocomposites for use as electrodes in electrochemical capacitors.