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Elucidating protonation pathways in CO₂ photoreduction using the kinetic isotope effect.

ABSTRACT: The surge in anthropogenic CO₂ emissions from fossil fuel dependence demands innovative solutions, such as artificial photosynthesis, to convert CO₂ into value-added products. Unraveling the CO₂ photoreduction mechanism at the molecular level is vital for developing high-performance photocatalysts. Here we show kinetic isotope effect evidence for the contested protonation pathway for CO₂ photoreduction on TiO₂ nanoparticles, which challenges the long-held assumption of electron-initiated activation. Employing isotopically labeled H₂O/D₂O and in-situ diffuse reflectance infrared Fourier transform spectroscopy, we observe H⁺/D⁺-protonated intermediates on TiO₂ nanoparticles and capture their inverse decay kinetic isotope effect. Our findings significantly broaden our understanding of the CO₂ uptake mechanism in semiconductor photocatalysts.

SUBMITTER: Yin S

PROVIDER: S-EPMC10781958 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Elucidating protonation pathways in CO2 photoreduction using the kinetic isotope effect.

Yin Shikang S Zhou Yiying Y Liu Zhonghuan Z Wang Huijie H Zhao Xiaoxue X Zhu Zhi Z Yan Yan Y Huo Pengwei P

Nature communications 20240110 1

The surge in anthropogenic CO2 emissions from fossil fuel dependence demands innovative solutions, such as artificial photosynthesis, to convert CO2 into value-added products. Unraveling the CO2 photoreduction mechanism at the molecular level is vital for developing high-performance photocatalysts. Here we show kinetic isotope effect evidence for the contested protonation pathway for CO2 photoreduction on TiO2 nanoparticles, which challenges ...[more]

PMID: 38200030

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