Photoelectrochemical CO₂ Reduction Measurements of a BiOI Coating Deposited Onto a Non‐Conductive Glass Support as a Platform for Environmental Remediation

Aiming to contribute to environmental remediation strategies, this work proposes a novel fabrication of photoelectrocatalytic electrodes containing a BiOI coating deposited onto non-conductive glass (NCG) for CO2 conversion applications. Since the BiOI electrodes are not deposited onto FTO or ITO conductive supports, the electrochemical measurements enable the registration of the (photo)electrochemical response for bare BiOI, thereby excluding remnant signals from the conductive support and reporting an exclusive and proper photoelectrocatalytic BiOI response. A systematic procedure was carried out to improve the physicochemical properties of BiOI through a simple variation of the reagents amount employed in a solvothermal synthesis, thus increasing the crystallite size and surface area of the resulting material (BiOI-X3-20wt.%). The tailored BiOI coating on a non-conductive support showed activity in performing the CO2 photoelectroreduction under UV-Vis irradiation in aqueous media. Finally, the BiOI-X3-20wt.% sample was evaluated to perform the photocatalytic CO2 conversion in gaseous media, producing CO as the reaction product. This study confirms that BiOI is a suitable and easily synthesized material with potential applications for CO2 capture and conversion when employed as a photoactive coating for environmental remediation.