Infrared light utilization based on pyroelectric effect to improve the efficiency and stability of BaTiO₃ for photocatalytic NO removal

Photocatalysis is a promising method for removing nitrogen oxides outdoor, However, the wide band gap of most photocatalysts usually causes the limited solar spectral response, which hinders the practical application of photocatalysts. In this paper, Sm_0.5Sr_0.5CoO₃ (SSC5) with good photothermal conversion performance is combined with BaTiO₃ for the effective utilization of sunlight as well as the prohibition of photogenerated carrier recombination. The introduce of SSC5 can rapidly improve the surface temperature of BaTiO₃ photocatalyst, which results in the increase of NO activation molecules and the generation of pyroelectric built-in electric field in BaTiO₃. Therefore, the photogenerated carrier can be fast migrated and separated. The performance of 3 wt% SSC5/BaTiO₃ is improved by 15% compared with the original sample. More interestingly, SSC5/BaTiO₃ exhibits good stability compared with pristine BaTiO₃. To analyse the reason for the improved stability, the energy of the reaction process on the catalyst surface was also simulate by DFT calculations. The results imply that the increased stability of SSC5/BaTiO₃ may rely on the transfer of holes on the BaTiO₃ to the SSC5. This study provides some new insights to the design of efficient and stable photocatalysts for NO removal in the environment.