AN IMPROVED PROCESS FOR THE PREPARATION OF SURFACE MODIFIED ZINC OXIDE SENSOR MATERIAL USEFUL FOR SENSING AMMONIA GAS

摘要

A process for the preparation of surface modified zinc oxide sensor material useful for sensing ammonia gas, which comprises of thoroughly mixing zinc oxide with a binder such as herein described, in presence of solvent such as herein described, drying the resultant mixture for 1-2 hours, compacting the dried powder under pressure of 5 to 10 tons, to obtain zinc oxide pellets, calcining the pellets so obtained at a temperature ranging between 500°C to 1QOO°C for a period of 5 to 16 hours, gradually reducing the temperature at the rate of l°C/min. to 3°C/min. to room temperature, immersing the pellets in a dilute solutions of a ruthenium such as herein described, for a period[ranging between 10 minutes and 15 hours, drying the pellets to incorporate 0.1-3 them heating the resultant pellets at a temperature ranging between 200 and 500 C for a period of 0.5 to 16 hours, to obtain the surface modified zine oxide