Sodium dodecylbenzene sulfonate-assisted synthesis of a carbon-cloth-based polyaniline flexible material for supercapacitors

Abstract

Carbon-cloth-based polyaniline flexible electrode materials were fabricated by a simple chemical oxidation method with the assistance of sodium dodecylbenzene sulfonate (SDBS) at different concentrations, where SDBS acts as a surfactant and dopant to control the morphology, structure and capacitance performance of the electrode material. TGA, BET, XRD, FT-IR, UV-vis and SEM analyses showed that a suitable amount of SDBS can enhance the interchain spacing of the polyaniline and the regularity of its main-chain structure as well as helping to vary its morphology (e.g., networks, spherical, or rod-like structures) on carbon cloth. More importantly, SDBS facilitated the bonding between polyaniline and carbon cloth, leading to the formation of good three-dimensional networks and spherical and rod-like structures, respectively. The insertion/de-insertion of electrolyte ions was easier due to the unique morphology and structure of materials prepared with SDBS, and the utilization ratio of polyaniline was also higher. Cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy tests revealed that of the three composites studied (PANI/CC-0,1,2, depending on the SDBS amount), PANI/CC-1 achieved the optimal capacitance performance, i.e., a high specific capacitance (up to 537 F g⁻¹ at the current density of 0.5 A g⁻¹, which is 31.9% higher than that without SDBS), high capacity retention (83.4% after 1000 charge–discharge cycles, compared to 46.9% for PANI/CC-0), and high energy density (74.5 W h kg⁻¹ at a power density of 0.25 kW kg⁻¹) as well as the best rate capability and the lowest impedance. In summary, the addition of a suitable amount of SDBS has a positive effect on improving the capacitance performance of carbon-cloth-based polyaniline electrodes.