Supercapacitor energy storage devices are well suited to meet the rigorous demands of future portable consumer electronics (PCEs) due to their high energy and power densities (i.e., longer battery-life and rapid charging, respectively) and superior operational lifetimes (10 times greater than lithium-ion batteries). To date, research efforts have been narrowly focused on improving the specific capacitance of these materials; however, emerging technologies are increasingly demanding competitive performance with regards to other criteria, including scalability of fabrication and electrochemical stability. In this regard, we developed a polyaniline (PANI) derivative that contains a carbazole unit copolymerized with 2,5-dimethyl-p-phenylenediamine (Cbz-PANI-1) and determined its optoelectronic properties, electrical conductivity, processability, and electrochemical stability. Importantly, the polymer exhibits good solubility in various solvents, which enables the use of scalable spray-coating and drop-casting methods to fabricate electrodes. Cbz-PANI-1 was used to fabricate electrodes for supercapacitor devices that exhibits a maximum areal capacitance of 64.8 mF cm–2 and specific capacitance of 319 F g–1 at a current density of 0.2 mA cm–2. Moreover, the electrode demonstrates excellent cyclic stability (≈ 83% of capacitance retention) over 1000 CV cycles. Additionally, we demonstrate the charge storage performance of Cbz-PANI-1 in a symmetrical supercapacitor device, which also exhibits excellent cyclic stabilitymore »
Simultaneous Electrochemical Deposition of Cobalt Complex and Poly(pyrrole) Thin Films for Supercapacitor Electrodes
Supercapacitors are beneficial as energy storage devices and can obtain high capacitance values greater than conventional capacitors and high power densities compared to batteries. However, in order to improve upon the overall cost, energy density, and charge-discharge rates, the electrode material of supercapacitors needs to be fine-tuned with an inexpensive, high conducting source. We prepared a Co(III) complex and polypyrrole (PPy) composite thin films (CoN4
- Publication Date:
- NSF-PAR ID:
- 10153375
- Journal Name:
- Scientific Reports
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2045-2322
- Publisher:
- Nature Publishing Group
- Sponsoring Org:
- National Science Foundation
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