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Characterization of Porous CuO Films for H₂S Gas Sensors.

ABSTRACT: Using a thermal evaporator, various porous Cu films were deposited according to the deposition pressure. CuO films were formed by post heat treatment in the air. Changes in morphological and structural characteristics of films were analyzed using field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Relative density and porosity were quantitatively calculated. CuO films with various pores ranging from 39.4 to 95.2% were successfully manufactured and were applied as gas sensors for H₂S detection on interdigitated electrode (IDE) substrate. Resistance change was monitored at 325 °C and an increase in porosity of the film improved the sensor performance. The CuO-10 gas sensor with a high porosity of 95.2% showed a relatively high response (2.7) and a fast recovery time (514 s) for H₂S 1.5 ppm. It is confirmed that the porosity of the CuO detection layer had a significant effect on response and recovery time.

SUBMITTER: Jung D

PROVIDER: S-EPMC9610780 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Characterization of Porous CuO Films for H2S Gas Sensors.

Jung Dawoon D Hwang Sehoon S Kim Hyun-Jong HJ Han Jae-Hee JH Lee Ho-Nyun HN

Materials (Basel, Switzerland) 20221018 20

Using a thermal evaporator, various porous Cu films were deposited according to the deposition pressure. CuO films were formed by post heat treatment in the air. Changes in morphological and structural characteristics of films were analyzed using field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Relative density and porosity were quantitatively calculated. CuO films with various pores ranging from 39.4 to 95.2% were successfully manufactured and were applied as ga ...[more]

PMID: 36295331

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