Chinese Journal of Magnetic Resonance >

2021 , Vol. 38 >Issue 3: 403 - 413

DOI: https://doi.org/10.11938/cjmr20202815

Articles

A Quantitative Study of Photocatalytic Reduction of Cr(Ⅵ) by Operando Low-Field NMR Relaxometry

  • Xing-xing NIU ,
  • Zhi-jie BAI ,
  • Yi YANG ,
  • Yang-wen GAO ,
  • Xue-lu WANG ,
  • Ye-feng YAO
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  • 1. Shanghai Key Laboratory of Magnetic Resonance, College of Physics and Electronic Science, East China Normal University, Shanghai 200062, China
    2. Shanghai Niumag Electronic Technology Co., Ltd., Shanghai 200333, China

Received date: 2020-03-09

  Online published: 2020-05-06

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Abstract

In this work, operando low-field nuclear magnetic resonance (LF-NMR) technology was used to quantitatively study the photocatalytic reduction of Cr(Ⅵ) in a real solid-liquid reaction environment. The performance of Ag/g-C3N4 photocatalysts with different loadings of Ag for the photocatalytic reduction of aqueous Cr(Ⅵ) to Cr(Ⅲ) under visible-light irradiation was systematically investigated. The results showed that the addition of Ag cocatalysts (Ag loading amount: 1 wt.%, 2 wt.%, 5 wt.%, and 10 wt.%) significantly enhanced the photocatalytic performance of g-C3N4 photocatalysts, while the optimal content of Ag loading was 5 wt.%, which was greater than that of pristine g-C3N4 by a factor of 4.0. Furthermore, we carried out a quantitative analysis on the concentration of paramagnetic Cr(Ⅲ) ions in solution by using the transverse relaxation time (T2) values, and proved the viability of employing operando LF-NMR relaxometry for monitoring the photocatalytic Cr(Ⅵ) reduction performance.

Key words： operando LF-NMR; g-C3N4; Ag loading; photocatalytic; Cr(Ⅵ) reduction; transverse relaxation time (T2)

Cite this article

Xing-xing NIU , Zhi-jie BAI , Yi YANG , Yang-wen GAO , Xue-lu WANG , Ye-feng YAO . A Quantitative Study of Photocatalytic Reduction of Cr(Ⅵ) by Operando Low-Field NMR Relaxometry[J]. Chinese Journal of Magnetic Resonance, 2021 , 38(3) : 403 -413 . DOI: 10.11938/cjmr20202815

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