ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Fabrication and electrochemical properties of flow-through polypyrrole and polypyrrole/polypyrrole nanoarrays

Yibing Xie

School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China

E-mail: ybxie@seu.edu.cn

Received: 25 July 2020  Accepted: 31 October 2020

Abstract:

Flow-through polypyrrole (PPY) nanoarrays are well tailored into nanopore, nanotube-in-nanopore and nanorod-in-nanopore structures to act as free-standing supercapacitor electrodes through anodization, electro-polymerization deposition and chemical corrosion processes. Independent TiO₂ nanotube array is prepared to act as well-aligned and ordered temperate by an anodic oxidation of titanium sheet. Polypyrrole (PPY) was selectively coated on the external surface and/or internal surface of TiO₂ nanotubes to form PPY/TiO₂ and PPY/TiO₂/PPY through a controlled pulse voltammetry electrodeposition process. Polypyrrole (PPY)/ Polypyrrole (PPY) nanotube-in-nanopore and nanorod-in-nanopore arrays can be formed by HF corrosion dissolution of TiO₂ template from PPY/TiO₂/PPY. Alternatively, PPY nanopore array can be formed by removing TiO₂ template from PPY/TiO₂. Polypyrrole (PPY) nanopore array has the pore diameter of 130–200 nm and wall thickness of 25–40 nm. Polypyrrole (PPY) Polypyrrole (PPY)/Polypyrrole (PPY) nanotube-in-nanopore array has the pore diameter of 135–225 nm, nanopore wall thickness of 25–45 nm and nanotube diameter of 90–135 nm. Polypyrrole (PPY)/ Polypyrrole (PPY) nanorod-in-nanopore array has the pore diameter of 115–215 nm, nanopore wall thickness of 20–35 nm and nanorod diameter of 85–135 nm. All these PPY and PPY/PPY nanoarrays have the total length of 0.9–1.1 μm and keep flow through and ordered alignment structure contributing to feasible electrolyte ion diffusion. Electroactive PY nanopore, PPY/PPY nanotube-in-nanopore and PPY/PPY nanorod-in-nanopore arrays directly become free-standing electrodes to achieve the specific capacitance of 13.2, 16.7 and 18.3mF cm⁻² at 0.25 mA cm⁻² in 1.0 M H₂SO₄ electrolyte and the rate capacity retention of 77.3, 77.2 and 77.0% at 1.5 mA cm⁻². Well-tailored and flow-through PPY and PPY/PPY nanoarrays can act as the promising polymer electrode materials for electrochemical energy storage.

Keywords: Polypyrrole; Nanoarray; Nanotube-in-nanopore; Nanorod-in-nanopore; Electrochemical

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01411-y

Chemical Papers 75 (5) 1831–1840 (2021)