https://www.jpcomplex.ir/Content/media/image/2013/08/772_orig.pdf

Electrochemical technologies in wastewater treatment

The paper critically reviews the state of the art in the field of experimental techniques possible to be applied to the study of conductometric gas sensors based on semiconducting metal oxides. The used assessment criteria are subordinated to the proposed R&D approach, which focuses on the study, and subsequent modelling, of sensors’ performance in realistic operation conditions by means of a combination of phenomenological and spectroscopic techniques. With this viewpoint, the paper presents both the to-date achievements and shortcomings of different experimental techniques, describes – by using selected examples – how the proposed approach can be used and proposes a set of objectives for the near future.

Metal oxide-based gas sensor research: How to?

SnO2: A comprehensive review on structures and gas sensors

Transparent conducting ZnO:Al, In and Sn thin films deposited by the sol–gel method

Discovery-based design of transparent conducting oxide films

Electrical and Optical-Properties of Sb-SnO2 Thin-Films Obtained by the Sol-Gel Method

Sb-doped SnO2 transparent conducting oxide from the sol-gel dip-coating technique

Morphology of SnO2 thin films obtaibed by the sol-gel technique

The antimony doping in SnO2 thin films prepared by the sol-gel dip-coating method has been studied using two characterization techniques. In order to determine the actual doping level directly in the deposited layers, X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS) have been used. We found that this doping level is systematically lower than expected from the starting solutions composition, and that two oxidation states are present: Sb3+ and Sb5+. As the antimony content increases, there is a competition between Sb5+ and Sb3+ species. The SnO2: Sb thin films have also been observed by transmission electron microscopy (TEM), showing that the measured mean size of crystallites decreases as the Sb content increases in the oxide. No precipitates of either Sn or Sb oxides (other than SnO2) could be detected.

Analysis of Antimony Doping in Tin Oxide Thin Films Obtained by the Sol-Gel Method

When prepared by the sol-gel dip-coating technique, doped tin oxide films need several superimposed layers to reach the expected low sheet resistance. In this paper we show that successive depositions increase the uniformity and homogeneity of multi-layered sol-gel tin oxide films. The final thickness is always found to be lower than a multiple of the initial first layer thickness, indicating that densification occurs. A strong improvement of physical properties is jointly observed in this multilayered configuration. All parameters (atomic density, refractive index, electrical resistivity, optical transmission and reflectivity) evolve towards bulk material values. This is explained by the fact that the sol, in which is dipped the substrate, fills in the pores or cracks remaining in the previously deposited layers. The quality of the sol-gel tin oxide stacked deposits obtained in such a way is evidenced by the M-line spectroscopy experiments presented in this paper. It is shown that multilayered coatings are able to guide light over some millimetres.

https://iopscience.iop.org/article/10.1088/0268-1242/14/7/310/pdf

J.P. Chatelon

Papers

Electrical and Optical-Properties of Sb-SnO2 Thin-Films Obtained by the Sol-Gel Method

Sb-doped SnO2 transparent conducting oxide from the sol-gel dip-coating technique

Morphology of SnO2 thin films obtaibed by the sol-gel technique

Analysis of Antimony Doping in Tin Oxide Thin Films Obtained by the Sol-Gel Method

Electrical and optical property enhancement in multilayered sol-gel-deposited SnO2 films