Polyaniline nanofiber/vanadium pentoxide sprayed layer-by-layer electrodes for energy storage
By Shao, Lin; Jeon, Ju-Won & Lutkenhaus, Jodie L.
Published in J. Mater. Chem. A
The Royal Society of Chemistry
2014
Abstract
Layer-by-layer assembly, as a low-cost process to create high-performance coatings, has been widely studied over the past 20 years. However, conventional layer-by-layer assembly is not well suited to large-area, large-scale and rapid application because of the long time scale required to complete a multilayer coating. Here, we develop a simple, water-based, rapid spray-on method to produce and prepare polyaniline/vanadium pentoxide layer-by-layer thin film cathodes for Li-ion batteries. This method uses spray-assisted LbL assembly, which is suitable to coating over large areas rapidly. The result is a water-processable hybrid cathode with high capacity (up to 232 mA h g-1 at a discharge current of 5 [small mu ]A cm-2), specific energy (up to 650 mW h g-1 at a discharge current of 0.5 [small mu ]A cm-2), specific power (up to 3395 mW g-1 at a discharge current of 25 [small mu ]A cm-2), and good cycle life. The performance is dependent on thickness and discharge rate. Compared to the traditional polyaniline/vanadium pentoxide prepared by dipping at a rate of 0.0373 nm s-1, sprayed electrodes grow at a significantly high rate of 0.42 nm s-1 - 11 times faster. This approach demonstrates the rapid layer-by-layer assembly of Li-ion battery electrodes without sacrificing performance.