Researchers at The University of Texas at Arlington have been the first to demonstrate that polyaniline (PANI), a member of the organic conducting polymer family, is a promising photocathode material for the conversion of carbon dioxide into alcohol fuels without the need for a co-catalyst.
In a proof-of-concept study published in the RSC journal ChemComm, the researchers provide insights into the unique behavior of polyaniline obtained from photoelectrochemical measurements and adsorption studies, together with spectroscopic data. They also compared the behavior of several conducting polymers.
Stationary currents recorded after two hours during testing suggested that the polyaniline layer maintained its photoelectrochemical efficacy for the studied time period. While in the gas phase, only hydrogen was detected, but potential fuels such as methanol and ethanol were both detected in the solution for carbon dioxide-saturated samples.
This opens up a new field of research into new applications for inexpensive, readily available organic semiconducting polymers within solar fuel cells.
Apart from these technical qualities, as a polymer, polyaniline can also be easily made into fabrics and films that adapt to roofs or curved surfaces to create the large surface areas needed for photoelectrochemical reduction, eliminating the need for expensive and dangerous solar concentrators.—principal researcher Krishnan Rajeshwar
Dorottya Hursán, Attila Kormányos, Krishnan Rajeshwar and Csaba Janáky (2016) “Polyaniline films photoelectrochemically reduce CO2 to alcohols” Chem. Commun., 52, 8858-8861 doi: 10.1039/C6CC04050K