Tunable bismuth doping/loading endows NaTaO₃ nanosheet highly selective photothermal reduction of CO₂

Photothermal CO₂ reduction with H₂O, integrating advantages of photocatalysis driven H₂O splitting and thermal catalysis promoted CO₂ reduction, has drawn sharply increasing attention in artificial synthesis of solar fuels. The photothermal effect of metal nanoparticles facilities CO₂ hydrogenation and activation of lattice oxygen in oxide photocatalyst promotes H₂O oxidation, which is essentially considered for highly efficient photothermal catalysis. However, the large thermal conductivity of most metal nanoparticles induces inevitable heat dissipation, restricting the increase of catalyst temperature. In this work, to minimize the heat dissipation, we employ bismuth nanoparticles as photothermal unit, which is of the lowest thermal conductivity in the metal family. Meanwhile, we adopt bismuth doped NaTaO₃ as photocatalytic unit because of the bismuth doping induced activation of lattice oxygen. The bismuth nanoparticles are assembled with bismuth doped NaTaO₃ through one-step tunable transformation from Bi₄TaO₈Cl. Benefiting from the photothermal effect, thermal insulation caused by bismuth metal, and lattice oxygen activation by bismuth doping, the NaTaO₃:Bi hybrid exhibits high photothermal catalytic performance. The yield of CO over NaTaO₃:Bi hybrid at 413 K via photothermal catalysis is 141 times higher than that room temperature photocatalysis. Further, ultraviolet (UV) light irradiation leads to 89.2% selectivity of CO and visible light irradiation leads to 97.5% selectivity of CH₄. This work may broaden the photocatalytic application of ABO₃ perovskite and provides a novel strategy for the development of photothermal catalysts for artificial photosynthesis.