Fe-doped ZnSnO3 cubes for high-performance detection of formaldehyde

ZnSnO3 is a typical metal semiconductor oxide (MOS), which has wide-band gap, n-type transport characteristics and excellent gas sensing performance. Fe doping plays a pivotal role in enhancing the formaldehyde sensing performance of ZnSnO3. In this paper, Fe-doped ZnSnO3 cubes were prepared successfully by a simple coprecipitation method. A series of characterization results show that Fe-doped ZnSnO3 is a cubic structure with uniform size of about 1.1 mu m, and Fe doping increases the specific surface area and oxygen vacancy, which is responsible for the enhanced sensing performance. The gas-sensing tests show that Fe-doped ZnSnO3 cubes have a significant selectivity for formaldehyde gas, and the response value of Fe-doped ZnSnO3 cubes (3 mol%) to 100 ppm formaldehyde gas is about 5 times that of pure ZnSnO3 at 200 degrees C. In addition, the sensor has a fast response/ recovery time (12/12 s), good recovery and reproducibility. Its excellent sensing performance is attributed to Fe doping, which leads to more defects and active sites in Fe-doped ZnSnO3 gas sensor. This work confirms that Fedoped ZnSnO3 is a promising preparation scheme for formaldehyde sensors.

Automated summary

This paper successfully prepared Fe-doped ZnSnO3 cubes and found that Fe-doped ZnSnO3 has high selectivity and response value for formaldehyde gas, as well as fast response/recovery time and good recovery performance.