Abstract
A nanoscale Co3O4–WO3 p–n junction sensor was established here. Via a two-step procedure (hydrothermal reaction/calcination), p-type Co3O4 nanoparticles were decorated on the surface of n-type WO3 nanorods (NRs). Characterization by SEM, TEM and XRD showed they contact intimately with each other. Via gas sensing test, the Co3O4–WO3 sensor displayed two times of response (Ra/Rg) than that of pure WO3 NRs sensor (toward 100 ppm acetone, 280 °C). Moreover, it also had a better selectivity towards acetone than that of pure WO3 NRs sensor. The mechanism analysis showed that its enhanced sensing performance was due to the extension of depletion layer in the p–n junction.









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The authors are grateful for financial support from the National Natural Science Foundation of China (Grant Nos. 51172157, 51202159).
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Zhao, X., Ji, H., Jia, Q. et al. A nanoscale Co3O4–WO3 p–n junction sensor with enhanced acetone responsivity. J Mater Sci: Mater Electron 26, 8217–8223 (2015). https://doi.org/10.1007/s10854-015-3484-3
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DOI: https://doi.org/10.1007/s10854-015-3484-3