High performance isopropanol sensor based on spinel ZnMn2O4 nanoparticles

Spinel-type ZnMn2O4 nanoparticles with sizes between 40 and 90 nm were synthesized successfully via an ultrasound-assisted colloidal method using dodecylamine as a surfactant agent. The formation of spinel ZnMn2O4 was identified from structural and morphological characterizations using X-ray diffraction, Raman spectroscopy, electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The ZnMn2O4 sensor exhibited good gas sensing performance to isopropanol vapor at an operating temperature of 250 degrees C. The sensor was able to detect concentrations of isopropanol in the range of 10-100 ppm, having a gas response from 22 to 99 %, respectively. A theoretical detection limit of 666 ppb with a gas response of similar to 5.2 % was estimated. The ZnMn2O4 sensor also showed a reproducible, repeatable, and stable electrical signal. The outstanding gas sensing performance revealed that the ZnMn2O4 can be used as a new sensing material for isopropanol vapor.