Photochemical reduction of CO(2) into CO coupling with triethanolamine decomposition

In this work, the impacts of triethanolamine (TEOA) on the performance of photochemical CO(2) reduction were investigated in a simple homogeneous system. We demonstrates that CO(2) can be converted into CO coupling with the decomposition of triethanolamine in TEOA aqueous solution without other additives under light irradiation. About 7.5 μmol CO product is achieved within 7 h with a maximum apparent quantum yield (AQY) of 0.086% at 254 nm. The isotope labelling experiment confirms that CO product originates from the reduction of CO(2) rather than the decomposition of TEOA. In addition, the photochemical system exhibits excellent stability, no obvious inactivation is observed during long-term photochemical CO(2) reduction reaction. This work provides a deep understanding of the effects of TEOA on the performance of photocatalytic CO(2) reduction. Upon utilizing TEOA as a sacrificial electron donor in photocatalytic system, the contribution of TEOA must be considered once evaluating the catalytic activity of catalysts.