Highly sensitive and ultra-fast gas sensor based on CeO2-loaded In2O3 hollow spheres for ppb-level hydrogen detection

• Published in: Sensors and actuators. B, Chemical Vol. 257; pp. 124 - 135
• Main Authors: Hu, Jie, Sun, Yongjiao, Xue, Yan, Zhang, Meng, Li, Pengwei, Lian, Kun, Zhuiykov, Serge, Zhang, Wendong, Chen, Yong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2018
• Subjects: CeO2-loaded In2O3; H2 gas sensor; Heterojunction; Hollow spheres; Hydrothermal method; Hollow spheres; Hydrothermal method; H2 gas sensor; CeO2-loaded In2O3; Heterojunction
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.10.139

The obtained CeO2-loaded In2O3 gas sensors exhibit enhanced gas sensing properties for hydrogen detection.
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•The different contents of CeO2-loaded In2O3 hollow spheres were synthesized by hydrothermal method.•The CeO2-loaded In2O3 gas sensors exhibit enhanced gas sensing properties comparing to the pristine one at 160°C.•The 2 at% CeO2-loaded In2O3 gas sensor shows highest response, fast response/recovery time and low detection limit toward H2 detection.•The enhanced gas sensing performance of CeO2-loaded In2O3 hollow spheres can be attributed to the heterostructures and transition of Ce ions.
H2 detection sensors based on pure and different contents of CeO2 (0.5 at%, 1 at%, 2 at%, 4 at%, 6 at%) loaded In2O3 hollow spheres were successfully fabricated. The crystal phase, morphology and chemical composition of the obtained CeO2-loaded In2O3 samples were analyzed by characteristic techniques. The gas sensing results showed that the CeO2-loaded In2O3 gas sensors exhibit enhanced H2 sensing performances compared with pure In2O3 at optimum working temperature (160°C). Especially, the gas sensor based on 2 at% CeO2-loaded In2O3 hollow spheres showed most improved properties: highly response (20.7–50ppm) at 160°C, which was about 3 times higher than that of pure In2O3 sensor (6.9); excellent response and recovery time of 1s and 9s; ultra-low detection of limit of 10 ppb; good repeatability and long-term stability. Finally, the enhanced gas sensing mechanism of CeO2-loaded In2O3 gas sensor towards H2 was also discussed.