Mechanism of drifts in H2S sensing properties of SnO2:CuO composite thin film sensors prepared by thermal evaporation

Characterization of CuO phase in SnO2–CuO prepared by the modified Pechini method

“…For samples without template, the CuO peak was not as intense but still detectable for CuO loadings of as little as 1% as evidenced from the peak areas plotted in Fig. 2.This is contrary to the published work of several authors who could not detect the CuO phase in the XRD of SnO 2 :CuO samples [11,18,19,27,28]. The peak intensity was stronger with increasing Cu loading suggesting that at a low Cu content, CuO was present in the form of nanoparticles while at a high Cu content, bulk CuO agglomerated particles were present.…”

“…In earlier reports, most of the studies on SnO 2 :CuO have been carried out on thick films prepared by an impregnation technique where CuO is dispersed on prepared SnO 2 particles and thereby CuO and SnO 2 particles remain separate [11]. This results in slower response times.…”

“…Thin film-based sensors are expected to have faster response times. In the case of thin films, the microstructure is expected to be different and may depend on preparation technique as the possibility of interaction between SnO 2 and CuO leading to homogeneous phase distribution exists and one may not expect CuO to be dispersed around SnO 2 grains [8,11,12].…”

“…Recently, we reported detailed investigations on the application of the Pechini method for the preparation of SrFeO X perovskite [16,17]. In this investigation we have used this method for the synthesis of SnO 2 :CuO hybrid for eventual sensor applications in the detection of H 2 S. The aim of this study was to characterize the CuO phase in SnO 2 :CuO, in view of the reported difficulty to detect CuO in the presence of SnO 2 at concentrations B5% [8,11,18,19]. The sample characterization was carried out by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), infrared spectroscopy (IR) and nitrogen adsorption isotherms (BET).…”

Investigations on humidity sensing of nanostructured tin oxide synthesisedviamechanochemical method

“…Sensors in the form of thin or thick films are very attractive because they have many advantages such as simple construction, low cost and miniature weight. They can be prepared by several techniques such as chemical vapour deposition, evaporation and sputtering [6][7][8][9]. Thick-film deposition of metal oxide materials is an advance technology that offers low cost and considerable versatility towards different applications.…”