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A ZnO/porous GaN heterojunction and its application as a humidity sensor.

ABSTRACT: A heterojunction of ZnO/porous GaN (ZnO/PGAN) was fabricated and directly applied to a diode-type humidity sensor. ZnO disks were loaded onto PGAN using a spraying process. The structure and surface morphology of the ZnO/PGAN were characterized using X-ray diffraction and scanning electron microscopy. The heterojunction displayed an excellent diode nature, which was investigated using photoluminescence spectra and I-V characteristics. The excellent transport capability of ZnO/PGAN contributes to enhanced electron transfer, and hence results in high sensitivity and quick response/recovery properties under different relative humidity (RH) levels. In the range of 12-96% RH, a fast sensing response time as low as 7 s and a recovery time of 13 s can be achieved. The simple design of a ZnO/PGAN based humidity sensor highlights its potential in various applications.

SUBMITTER: Wang C

PROVIDER: S-EPMC9473300 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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A ZnO/porous GaN heterojunction and its application as a humidity sensor.

Wang Chao C Huang Hui H Zhang Miao-Rong MR Song Wei-Xing WX Zhang Long L Xi Rui R Wang Lu-Jia LJ Pan Ge-Bo GB

Nanoscale advances 20181221 3

A heterojunction of ZnO/porous GaN (ZnO/PGAN) was fabricated and directly applied to a diode-type humidity sensor. ZnO disks were loaded onto PGAN using a spraying process. The structure and surface morphology of the ZnO/PGAN were characterized using X-ray diffraction and scanning electron microscopy. The heterojunction displayed an excellent diode nature, which was investigated using photoluminescence spectra and <i>I</i>-<i>V</i> characteristics. The excellent transport capability of ZnO/PGAN ...[more]

PMID: 36133180

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