Temperature Optimized Ammonia and Ethanol Sensing Using Ce Doped Tin Oxide Thin Films in a Novel Flow Metric Gas Sensing Chamber

Abstract

A simple process of gas sensing is represented here using Ce doped tin oxide nanomaterial based thin film sensor. A novel flow metric gas chamber has been designed and utilized for gas sensing. Doping plays a vital role in enhancing the sensing properties of nanomaterials. Ce doped tin oxide was prepared by hydrothermal method and the same has been used to fabricate a thin film for sensing. The microstructure and morphology of the prepared materials were analysed by SEM, XRD, and FTIR analysis. The SEM images clearly show that doping can clamp down the growth of the large crystallites and can lead to large agglomeration spheres. Thin film gas sensors were formed from undoped pure SnO2and Ce doped SnO2. The sensors were exposed to ammonia and ethanol gases. The responses of the sensors to different concentrations (50–500 ppm) of ammonia and ethanol at different operating temperatures (225°C–500°C) were studied. Results show that a good sensitivity towards ammonia was obtained with Ce doped SnO2thin film sensor at an optimal operating temperature of 325°C. The Ce doped sensor also showed good selectivity towards ammonia when compared with ethanol. Pure SnO2showed good sensitivity with ethanol when compared with Ce doped SnO2thin film sensor. Response time of the sensor and its stability were also studied.

Low-cost ultra-sensitive SnO2-based ammonia sensor synthesized by hydrothermal method

“…FTIR spectroscopy analysis of Ce-doped SnO 2 revealed that the absorption band at 3411.55 cm −1 accorded with the Sn-OH group. An important peak appeared near 667.49 cm −1 is owing to the antisymmetric stretching mode of Sn-O-Sn of the surface bridging oxide created attributable to the condensation of near to the surface vibrations of the -OH group [35]. This peak validates the successful formation of the SnO 2 nanoparticle.…”

Industrial measurement system with LoRa interface

“…This facility can save time and installation costs. Such units, being portable, can be connected at any suitable measurement point on a shop floor to measure certain parameters such as water flow, gas flow, 4 displacement, air pressure, and so on.…”