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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.


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

Show Author's information Mengmeng ZhangChanghua Wang( )Yueyun WangSongmei LiXintong Zhang( )Yichun Liu
Key Laboratory of Ultraviolet (UV)-Emitting Materials and Technology of Chinese Ministry of Education, Northeast Normal University, Changchun 130024, China

Abstract

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.

Keywords: CO2 reduction, bismuth, photothermal catalytic, high selectivity, NaTaO3

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Publication history

Received: 25 June 2022
Revised: 19 August 2022
Accepted: 23 August 2022
Published: 07 October 2022
Issue date: February 2023

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© Tsinghua University Press 2022

Acknowledgements

Acknowledgements

This work was supported by the Natural Science Foundation of China (Nos. 91833303, 52273236, and 51872044), the 111 Project (No. B13013), and Jilin Province Science and Technology Development Project (No. 20220201073GX).

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