CdO-based nanostructures as novel CO₂gas sensors

Abstract

Crystalline Cd(OH) 2 /CdCO 3 nanowires, having lengths in the range from 0.3 up to several microns and 5-30 nm in diameter, were synthesized by a microwave-assisted wet chemical route and used as a precursor to obtain CdO nanostructures after a suitable thermal treatment in air. The morphology and microstructure of the as-synthesized and annealed materials have been investigated by scanning electron microscopy, transmission electron microscopy, x-ray diffraction and thermogravimetry-differential scanning calorimetry. The change in morphology and electrical properties with temperature has revealed a wire-to-rod transformation along with a decreases of electrical resistance.Annealed samples were printed on a ceramic substrate with interdigitated contacts to fabricate resistive solid state sensors. Gas sensing properties were explored by monitoring CO 2 in synthetic air in the concentration range 0.2-5 v/v% (2000-50 000 ppm). The effect of annealing temperature, working temperature and CO 2 concentration on sensing properties (sensitivity, response/recovery time and stability) were investigated. The results obtained demonstrate that CdO-based thick films have good potential as novel CO 2 sensors for practical applications.

Microwave irradiated Sn-substituted CdO nanostructures for enhanced CO2 sensing

“…From the earlier report, undoped CdO prepared by microwave irradiation method, has been proposed as sensing layer for resistive CO 2 sensor [23]. The reported results indicate that the undoped CdO shows promising characteristics of for CO 2 sensing.…”

Effect of annealing and chemical treatment on structural and optical properties of CuPcTs/PEDOT:PSS (BHJ Blend) thin films

“…where λ, Ө and n represent X-ray wavelength from Cu target (1.5406 Å), diffraction angle and diffraction order respectively. The X-ray diffraction peaks full width at half maximum (FWHM) used to determine the crystalline size as shown in Scherrer formula [15].…”

Structural and Optoelectronic Characterization of CdO/Si Solar Cell Prepared by DC Magnetron Sputtering

“…Cadmium oxide (CdO) is n-type semiconductor with direct energy gap (2.2 -2.5 ) eV [1].CdO thin films deposited by different techniques such asspray pyrolysis [2],DC sputtering [3],Sol-Gel [4] and Chemical bath methods [5] etc.…”