Enhanced electrochemical performance of polyaniline-based electrode for supercapacitors in mixed aqueous electrolyte. (20th July 2020)

• Record Type: Journal Article
• Authors: Wang, Qi; Li, Jinmei; Wang, Dongshan; Niu, Jingye; Du, Pengcheng; Liu, Juanli; Liu, Peng
• Is Part Of: Electrochimica acta. Volume 349(2020)
• Publication Date: 2020-07-20
• Subjects: Supercapacitors -- Polyaniline-based electrode -- Aqueous electrolyte -- Acidity -- Ion strength; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.136348
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Aqueous electrolytes can provide high capacitance owing to their high ionic conductivity. In the present work, the aqueous electrolyte was optimized for the polyaniline (PANI)-based electrode, with a flexible PANI coated polylactic acid/multi-walled carbon nanotubes (PLA/MWCNTs) composite film as a model electrode. The electrochemical performance of the PLA/MWCNTs composite film electrode was investigated in the most used acidic and neutral electrolytes, H2 SO4 and Na2 SO4 . As a result, the optimized aqueous electrolyte for the PANI-based electrodes in supercapacitor was achieved as 1.1 mol L −1 H2 SO4 /0.1 mol L −1 Na2 SO4 mixed electrolyte (1.1–0.1), in which the specific capacitance was enhanced by 17.28% in comparison with the commonly used acidic electrolyte (1.0 mol L −1 H2 SO4 ). The analysis of the electrode and electrolytes after electrochemical cycles demonstrated that the addition of the neutral electrolyte Na2 SO4 could efficiently inhibit the acid-induced hydrolysis of PANI, improving the specific capacitance and cycling stability. The finding is expected to promote the development of the advanced aqueous polyaniline-based supercapacitors. Graphical abstract: Image 1 Highlights: Aqueous electrolyte was optimized for PANI-based electrode in supercapacitor. Specific capacitance was enhanced with the H2 SO4 /Na2 SO4 mixed electrolyte. Cycling stability was improved with the H2 SO4 /Na2 SO4 mixed electrolyte.