In this work, SnO2 hollow microspheres functionalized with different incorporated amounts of Pt@Co3O4 complex catalyst were innovatively designed by using an MOF template. The results show that sensor based on the optimal incorporated amount of Pt@Co3O4 not only greatly enhances the response value of SnO2 to formaldehyde (Rair/Rformaldehyde = 4240 toward 100 ppm) but also decreases the low detection limit (50 ppb), which is quite outstanding compared with other SnO2-based formaldehyde sensors. Further analysis proves that the content of oxygen vacancy and chemisorbed oxygen and the catalytic effect of ultra-small Pt play the key roles in improving the formaldehyde sensing performance. Meanwhile, this present work demonstrates that oxide semiconductors functionalized with the derivatives of MOF templated catalysts may lead to the discovery of new material systems with outstanding sensing performance.
Keywords: Pt@Co3O4; SnO2 hollow microspheres; formaldehyde; oxygen deficient.