Preparation of ZnO semiconductor formaldehyde gas sensor

Aimed at the current interior decoration formaldehyde pollution problems, through the analysis of the metal oxide semiconductor gas sensor characteristics and sensing mechanism, this paper combined with the influence of nanotechnology on sensor performance and designed semiconductor-type ZnO formaldehyde gas sensor. Prepared nano-ZnO using the sol-gel, doped H₂PtCl₆, La₂O₃ according to a certain proportion, sintered at 500°C for 3 hours and inorganic semiconductor sensitive material was compounded. By scanning electron microscopy (SEM) and differential thermal analyzer (DTA) the test results showed that the powder prepared was the nano-particle, the small particle size, and dispersion; sintering temperature was above 445°C. The sensor performance was test, the results showed that: the optimum operating voltage of the sensor was 4.8V, sensitivity was 5ppm, response time was 6s, detection range was 5-155ppm, and selectivity to alcohol, gasoline, carbon monoxide and other gases was high.