Using a spin-spray layer-by-layer (SSLbL) assembly technique the researchers created ultrathin and transparent films from single-walled carbon nanotubes (SWNT) and vandium pentoxide (V2O5) nanowires to serve as battery anodes and cathodes.
According to Taylor control over deposition has long been an issue with films containing one-dimensional nanomaterials. The materials may promising for sensor and electrode applications, but achieving uniform properties - such as conductivity -throughout the film has proved difficult. The Yale researchers are looking to produce electrodes with nano-level precision using SSLbL assembly, a method previously developed in Taylor’s lab.
“We demonstrate the feasibility of making transparent battery anodes and cathodes with this highly controllable solution-based method,” said Gittleson. “Engineering ultrathin films to store lithium ions reliably is not trivial. What we have achieved, while only a first step, is quite a feat.”
There are still challenges to overcome before transparent devices can be mass-produced. “The biggest obstacle we face is improving the conductivity of these thin electrodes,” said Gittleson. To address this, the researchers created a new “sandwich” architecture that integrates conductive SWNT layers and active cathode materials to enhance performance.