Mixed Perovskite Phases of BaTiO3/BaTi5O11 for Efficient Electrochemical Reduction of CO2 to CO

Abstract One of the most promising approaches in solving the energy crisis and reducing atmospheric CO 2 emissions is artificial photosynthetic CO 2 reduction. The electrochemical method for CO 2 reduction is more appealing since it can be operated under ambient conditions, and the product selectivity strongly depends on the applied potential. Perovskites with ferroelectric properties strongly adsorb linear CO 2 molecules. In this study, barium titanate (BaTiO 3 ) perovskite is used as an electrocatalyst to promote CO 2 activation and conversion to CO. Perovskite catalysts were prepared by ball‐milling followed by annealing at 900 °C for 4 to 6 h in an open atmosphere. The TEM and SEM study shows that the particle size varies in the range of 80–200 nm. Mixed phases of BaTiO 3 and BaTi 5 O 11 supported on nitrogen‐doped carbon nanotubes are found to be highly active for electrocatalytic CO 2 reduction to CO with maximum Faradaic efficiency of 89.4 % at −1.0 V versus Ag/AgCl in CO 2 saturated 0.5 KOH solution. This study concludes that mixed phases of BaTiO 3 and BaTi 5 O 11 are more active and highly selective for CO 2 conversion to CO compared to single‐phase BaTiO 3 .