Humidity-independent electronic nose of α-Fe2O3/ZnFe2O4 heterojunctions for trace detection of N-butanol exhalation in lung cancer screening

• Published in: Sensors and actuators. B, Chemical Vol. 384; p. 133577
• Main Authors: Yan, Wenqian, Liu, Wei, Zhao, Zhiyang, Wang, Jinghan, Nam, Gi Baek, Cui, Sheng, Shen, Xiaodong, Jang, Ho Won
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2023
• Subjects: Electronic nose; Humidity independence; Lung cancer screening; N-butanol detection; N-n heterojunctions; N-n heterojunctions; N-butanol detection; Humidity independence; Lung cancer screening; Electronic nose
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2023.133577

Magnetic metal oxide semiconductors (MOSs) are emerging gas-sensing materials. Most researches were devoted to monitoring large-scale gases in industrial emissions, but the trace detection of electronic noses applied in health diagnosis was always ignored. Herein, the humidity-independent α-Fe2O3/ZnFe2O4 (FZFO) heterojunctions with strong magnetism for N-butanol gas detection were prepared. They may potentially act as electronic noses in early lung cancer screening. This magnetism can endow FZFO to capture more oxygen for redox, and the n-n heterojunctions generated can significantly enhance gas sensitivity, improving the response even under 0.1 ppm at 160 ℃. Furthermore, the limit of detection of the FZFO-4 sample can reach 1 ppb, completely meeting the accuracy requirements. Notably, the humidity independence of FZFO-2 and FZFO-4 samples could maintain at relative humidity 91%, so they will hardly be influenced by water vapor exhaled from patients' mouths. This work first proposed the electronic nose of FZFO heterojunctions in lung cancer screening, which may initiate a wave of non-invasive diagnosis. •N-butanol detection at low concentrations in lung cancer screening was first proposed.•The interactional crystal sizes were influenced by their dispersed phase particles and volume fraction.•The LOD of FZFO-4 can reach 1 ppb at 160 ℃ and 47% humidity.•The magnetism can help sensors capture more oxygen.•The humidity independence endowed FZFO-2 and FZFO-4 with more practicability.