Making Supercapacitor Microelectrodes from Waste Carbon
Researchers created composite materials for use in supercapacitor microelectrodes by incorporating waste carbon into PANI polymers. Nanoscale characterization of structure and electrical behavior provided insight into the materials’ excellent electrochemical performance.
Electrodes made of conductive polymers are an exciting prospect for supercapacitors and other energy storage applications. Their appeal would be even greater if they could be produced more sustainably, for instance by recycling carbon-based materials.
A team of Portuguese and South Korean researchers pursued this idea using carbon nanoparticles derived from kitchen-oven waste carbon (WCP) and the conductive polymer polyaniline (PANI). They created composite materials (Pa/WC) from these ingredients via a simple and cost-effective wet-chemical route.
The composite materials were evaluated by AFM structural and nanoelectrical characterization, energy dispersive x-ray spectroscopy (EDS) compositional analysis, and other methods. Microstructural imaging was used to compare samples made with different amounts of WCP and varying polymerization times. Electrodes made from the composites had outstanding electrochemical performance including high charge storage, good rate capability, and cyclic stability. These properties were better understood by nanoelectrical measurements that probed the composites’ unique charge-trapping behavior and other effects.
The results demonstrate a ‘reuse and recycle’ strategy that could help achieve high-performance energy storage systems based on low-cost, sustainable materials.
AFM imaging in tapping mode was used to measure surface roughness (height channel) and examine nanoparticle dispersion (phase channel). Nanoelectrical characterization was performed with electrostatic force microscopy (EFM) to examine local charging effects and Kelvin probe force microscopy (KPFM) to determine surface potential differences. All AFM data were acquired on an MFP-3D AFM and demonstrate its versatility and high performance for a low price. EDS elemental mapping of the as-collected waste carbon nanoparticles was performed with an X-Max 150 Silicon Drift Detector by Oxford Instruments NanoAnalysis (since upgraded to Ultim Max) coupled to a field-emission scanning electron microscope (FE-SEM).
Citation: S. Goswami, G. Dillip, S. Nandy et al., Biowaste-derived carbon black applied to polyaniline-based high-performance supercapacitor microelectrodes: Sustainable materials for renewable energy applications. Electrochim. Acta316, 202 (2019). https://doi.org/10.1016/j.electacta.2019.05.133
Note: The data shown here are reused under fair use from the original article, which can be accessed through the article link above.