Green synthesis of tin oxide based nanoparticles using Terminalia bellirica seed extract: impact of operating temperature and antimony dopant on sensitivity for carbon dioxide gas sensing application

ABSTRACT

Green synthesis of undoped tin oxide (SnO₂) and 2 wt% antimony doped tin oxide (Sb:SnO₂) for carbon dioxide (CO₂) gas sensing application is reported. The structural, morphological and optical properties of nanoparticles were investigated using XRD, SEM, EDX, HRTEM, FTIR and UV-Vis characterisation techniques. CO₂ gas sensing studies were carried out by using calibration setup on pellets of nanoparticles. From XRD, SEM and HRTEM analysis, the average size of Sb:SnO₂ nanoparticles were found decreased than the SnO₂ nanoparticles. EDX analysis indicated the presence of tin, antimony and oxygen elements in the structure of nanoparticles. The presence of functional groups responsible for the formation of nanoparticles was identified by FTIR spectra. Bandgap of SnO₂ and Sb:SnO₂ nanoparticles was found to be 3.67 eV and 3.47 eV respectively. The sensitivity of SnO₂ and Sb:SnO₂ nanoparticles at the optimized operating temperature was found as 18.32% and 35% at 1000 ppm CO₂ gas concentration.     

KEYWORDS:

• Green synthesis
• SnO₂
• Sb:SnO₂
• nanoparticles
• carbon dioxide
• sensitivity

Acknowledgments

The authors are thankful to Siddaganga Institute of Technology, Tumakuru, Karnataka, India, for providing facilities to carry out research activities and CENSE, IISc, Bangalore, for providing gas-sensing characterization facility under Indian Nano Users Program (INUP).

Disclosure statement

No potential conflict of interest was reported by the author(s).