Favoring Product Desorption by a Tailored Electronic Environment of Oxygen Vacancies in SrTiO 3 via Cr Doping for Enhanced and Selective Electrocatalytic CO 2 to CO Conversion.

The electrochemical CO 2 reduction reaction (ECO 2 RR) into value-added products is crucial to address the herculean task of CO 2 mitigation. Several efforts are being made to develop active ECO 2 RR catalysts, targeting enhanced CO 2 adsorption and activation. A rational design of ECO 2 RR catalysts with a facile product desorption step is seldom reported. Herein, ensuing the Sabatier principle, we report a strategy for an enhanced ECO 2 RR with a faradaic efficiency of 85% for CO production by targeting the product desorption step. The energy barrier for product desorption was lowered via a tailored electronic environment of oxygen vacancies (O vac ) in Cr-doped SrTiO 3 . The substitutional doping of Cr 3+ for Ti 4+ into the SrTiO 3 lattice favors the generation of more O vac and modifies the local electronic environment. Density functional theory analysis evinces the spontaneous dissociation of COOH # intermediates over O vac and lower CO intermediate binding on O vac reducing the energy demand for CO release due to Cr doping.