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Capacitive humidity sensing properties of freestanding bendable porous SiO₂/Si thin films.

ABSTRACT: The fabrication of freestanding bendable films without polymer substrates is demonstrated as a capacitive humidity-sensing material. The bendable and porous SiO₂/Si films are simply prepared by electrochemical-assisted stripping, metal-assisted chemical etching, followed by oxidation procedures. The capacitive humidity-sensing properties of the fabricated porous SiO₂/Si film are characterized as a function of the relative humidity and frequency. The remarkable sensing performance is demonstrated in the wide RH range from 13.8 to 79.0%. The sensing behavior of the porous SiO₂/Si film is studied by electrochemical impedance spectroscopy analysis. Additionally, the reliability of the porous SiO₂/Si sensing material is confirmed by cyclic and long-term sensing tests.

SUBMITTER: Park S

PROVIDER: S-EPMC9270390 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Capacitive humidity sensing properties of freestanding bendable porous SiO2/Si thin films.

Park Soobin S Seo Jinmyeong J Park Jungjoon J Hwang Inseong I Lee Han-Seung HS Jung Hyunsung H Yoo Bongyoung B

Scientific reports 20220708 1

The fabrication of freestanding bendable films without polymer substrates is demonstrated as a capacitive humidity-sensing material. The bendable and porous SiO2/Si films are simply prepared by electrochemical-assisted stripping, metal-assisted chemical etching, followed by oxidation procedures. The capacitive humidity-sensing properties of the fabricated porous SiO2/Si film are characterized as a function of the relative humidity and frequency. The remarkable sensing perfo ...[more]

PMID: 35804095

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