Electrochemical characterization of RuO2-Ta2O5/polyaniline composites as potential redox electrodes for supercapacitors and hydrogen evolution reaction. (28th August 2020)

• Record Type: Journal Article
• Authors: Kuo, Chung-Wen; Chang, Jui-Cheng; Wu, Bo-Wei; Wu, Tzi-Yi
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 42(2020)
• Page Start: 22223
• Page End: 22231
• Publication Date: 2020-08-28
• Subjects: Ruthenium oxide -- Tantalum oxide -- Polyaniline -- Composite electrode -- Supercapacitor; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2019.08.059
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: RuO2 -Ta2 O5 electrode covered with polyaniline (PANI) was prepared by sintering and electrodeposition. X-ray photoelectron spectroscopy confirmed the presence of RuO2 -Ta2 O5 and PANI and the strong interaction between RuO2 -Ta2 O5 and PANI in the RuO2 -Ta2 O5 /PANI composite. The crystalline structure of RuO2 -Ta2 O5 /PANI was verified by XRD. SEM analysis revealed that the RuO2 -Ta2 O5 /PANI electrode had a nano-fibrous morphology with a crystal plane and some pores. The supercapacitive performance of RuO2 -Ta2 O5 /PANI was evaluated by cyclic voltammetry and charge-discharge chronopotentiometry. RuO2 -Ta2 O5 /PANI had a high specific capacitance (428 F/g), specific energy (26.7 Wh/kg at a discharge current density of 0.5 mA/cm 2 ), and power density (2.4 kW/kg at a discharge current density of 4.0 mA/cm 2 ). The attractive capacitive properties of RuO2 -Ta2 O5 /PANI may be attributed to the porous morphology of RuO2 -Ta2 O5 covered with PANI. In addition, the as-prepared RuO2 -Ta2 O5 and RuO2 -Ta2 O5 /PANI electrodes had Tafel slopes of −55.8 and −69.2 mV/dec, respectively, which make them potential H2 evolution electrocatalysts. Highlights: RuO2 -Ta2 O5 electrode covered with PANI was prepared by sintering and electrodeposition. RuO2 -Ta2 O5 /PANI can be used as electrodes for pseudocapacitors. RuO2 -Ta2 O5 /PANI electrode displays a Tafel slope of −69.2 mV/dec. RuO2 -Ta2 O5 /PANI electrode exhibits a specific capacitance of 428 F/g. RuO2 -Ta2 O5 /PANI electrode reveals high specific energy.