Gas-solid interfacial charge transfer in volatile organic compound detection by CuCrO2nanoparticles

Sifan Xu; Tingting Zhao; Lingwei Kong; Wenhuan Zhu; Maolin Bo; Yizhong Huang; Hai Liu

doi:10.1088/1361-6528/abfa55

Gas-solid interfacial charge transfer in volatile organic compound detection by CuCrO₂nanoparticles

Nanotechnology. 2021 May 10;32(31). doi: 10.1088/1361-6528/abfa55.

Authors

Sifan Xu¹, Tingting Zhao¹, Lingwei Kong², Wenhuan Zhu², Maolin Bo³, Yizhong Huang⁴, Hai Liu¹

Affiliations

¹ Key Laboratory of Advanced Display and System Applications of Ministry of Education, Shanghai University, 149 Yanchang Road, Shanghai, 200072, People's Republic of China.
² Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
³ Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology (EBEAM) of Chongqing, Yangtze Normal University, Chongqing 408100, People's Republic of China.
⁴ School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore.

PMID: 33882474
DOI: 10.1088/1361-6528/abfa55

Abstract

Nanostructured metal oxide semiconductors have received great attention used as the chemiresistive layer of gas sensor to detect the volatile organic compound recently. As indispensable complementary parts for dominative n-type semiconductors, the p-type metal oxides based gas sensors fail to be studied sufficiently, which hampers their practical applications. In this work, the p-type delafossite CuCrO₂nanoparticles were synthesized, characterized, and tested for gas sensing, followed by the first principles calculations to simulate the generation of chemiresistive signal. The hydrothermal synthesis time of CuCrO₂nanoparticles is optimized as 24 h with a higher proportion of oxygen vacancies but a smaller size, which is confirmed by the microscopy and spectrum characterization and allows for a prevailing gas sensitivity. Meanwhile, this CuCrO₂gas sensor is proven to perform a higher selectivity to n-propanol and a low detection limit of 1 ppm. The adsorption sites and charge variations of dehydrogenation at the gas-solid interface predicted by the theoretical analysis are claimed to be crucial to such selectivity. It is an innovative approach to understand the chemiresistive gas sensing by evaluating the preference of charge transfer between the sensor and target gaseous molecule, which provides a new route to precisely design and develop the advanced sensing devices for the diverse applications.

Keywords: CuCrO2; gas sensor; metal oxide semiconductor; volatile organic compound.