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Enhanced NO₂ Sensing Performance of ZnO-SnO₂ Heterojunction Derived from Metal-Organic Frameworks.

ABSTRACT: Nitrogen dioxide (NO₂) is the major reason for acid rain and respiratory illness in humans. Therefore, rapid, portable, and effective detection of NO₂ is essential. Herein, a novel and simple method to construct a ZnO-SnO₂ heterojunction is fabricated by pyrolysis of bimetallic metal organic frameworks. The sensitivity of ZnO-SnO₂ heterojunction towards 0.2 ppm NO₂ under 180 °C is 37, which is 3 times that of pure ZnO and SnO₂. The construction of heterojunction speeds up the response-recovery process, and this kind of material exhibits lower detection limit. The construction of heterojunction can significantly improve the NO₂ sensitivity. The selectivity, stability, and moisture resistance of ZnO-SnO₂ heterojunction are carried out. This could enable the realization of highly selective and sensitive portable detection of NO₂.

SUBMITTER: Ren X

PROVIDER: S-EPMC9658193 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Enhanced NO2 Sensing Performance of ZnO-SnO2 Heterojunction Derived from Metal-Organic Frameworks.

Ren Xiaowei X Xu Ze Z Zhang Zhongtai Z Tang Zilong Z

Nanomaterials (Basel, Switzerland) 20221023 21

Nitrogen dioxide (NO2) is the major reason for acid rain and respiratory illness in humans. Therefore, rapid, portable, and effective detection of NO2 is essential. Herein, a novel and simple method to construct a ZnO-SnO2 heterojunction is fabricated by pyrolysis of bimetallic metal organic frameworks. The sensitivity of ZnO-SnO2 heterojunction towards 0.2 ppm NO2 under 180 °C is 37, which is 3 times that of pure ZnO and SnO2. Th ...[more]

PMID: 36364502

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