One-dimensional lepidocrocite titania mesoparticles integrated with activated carbon for high-performance supercapacitor applications
Year: 2024
Type: article
Abstract: Herein we mix lepidocrocite titania-based, TiO2, porous mesoparticles, comprised of one-dimensional lepidocrocite nanofilaments, 1DLs, with activated carbon, AC, to create a unique composite structure with exceptional electrochemical properties. The synthesis method is facile, cost-effective, and scalable. While the porous mesoparticles, PMs, possess excellent protonic conductivity and exhibit enhanced faradic behavior in acidic aqueous media, their low electronic conductivity restricts their power output. The problem is solved by mixing the PMs with AC powders with various loadings. Electrolytes used were sulphuric acid, H2SO4, potassium hydroxide, KOH, lithium and Na-sulphates. The best PM loading was found to be 25 wt.%. The resulting composite exhibits a specific capacitance of 1,082 Fg-1, with a specific energy of 571 Whkg-1 at a 2 mVs-1 scan rate, with 97% cyclic stability over 10,000 cycles when the electrolyte was 1M H2SO4. When the composite was assembled in a symmetric device, the specific energy was 92 Whkg-1 at 0.3 Ag-1. The highest specific power was 3,900 Wkg-1, while maintaining a specific energy of 59 Whkg-1 at 2 Ag-1. After 100,000 cycles, at 1 Ag-1, the symmetric cell maintained ≈ 50% of its initial specific capacitance. A 24 h self-discharge test revealed the cell voltage drops from 1.95 V to 0.23 V, restricting the applications of these supercapacitors for long-term energy storage. More work is thus needed to enhance the lifetime and reduce self-discharge.
Source: Journal of Energy Storage
Institutions: Linköping University, Drexel University
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,030
OpenAlex ID: W4402865216