Synthesis of tin oxide thin films incorporating nanostructured europium oxide via pulsed laser deposition for NO2 sensing applications

Saleh, Noor; Rzaij, Jamal M.

doi:10.37652/juaps.2025.165404.1706

	Synthesis of tin oxide thin films incorporating nanostructured europium oxide via pulsed laser deposition for NO2 sensing applications
Journal of University of Anbar for Pure Science
Volume 20, Issue 2, August 2026, Pages 295-308 PDF (2.38 M)
Document Type: Research Paper
DOI: 10.37652/juaps.2025.165404.1706
Authors
Noor Saleh; Jamal M. Rzaij^*
Department of Physics, College of Science, University Of Anbar, Ramadi, Iraq
Abstract
In this work, nanostructured tin oxide thin films (SnO2) were deposited on silicon substrates at room temperaturIn this work, nanostructured tin oxide (SnO2) thin films were deposited on silicon substrates at room temperature using pulsed laser deposition (PLD). The study focused on the effect of mixing SnO2 films with europium oxide (Eu2O3) at different weight ratios of 5, 7, and 9 wt% on the gas-sensing properties of the prepared films. X-ray diffraction (XRD) analysis revealed that the addition of Eu2O3 contributed to the formation of separate SnO, SnO2, and Eu2O3 phases, which significantly improved nitrogen dioxide (NO2) sensing performance. Surface morphology analysis showed that particle distribution varied with increasing Eu2O3 content. In particular, the sample containing 7 wt% Eu2O3 exhibited a narrower particle size distribution and more homogeneous particle growth on the sensor surface, resulting in the highest sensitivity among the prepared samples. The thickness of the deposited films increased with increasing Eu2O3 content, although a slight decrease in thickness was observed for the sample containing 5 wt% Eu2O3. Gas-sensing results against different NO2 concentrations showed that the optimum operating temperature was 200 °C. The SnO2 film mixed with 7 wt% Eu2O3 exhibited the highest sensitivity of 626% at 120 ppm NO2, with a response time of 10 s and a recovery time of 12 s. These findings indicate that Eu2O3 mixing can enhance the sensing properties of SnO2 by modifying its nanostructure and surface morphology, increasing oxygen-vacancy concentration, and improving sensitivity under different environmental conditions.e using pulsed laser deposition (PLD). The study focused on the effect of mixing SnO2 films with europium oxide (Eu2O3) at varying weight ratios (5, 7, and 9 wt%) on the gas sensing properties of the developed films. X-ray diffraction (XRD) revealed that the addition of Eu2O3 contributed to the growth of separate phases of SnO, SnO2, and Eu2O3, which significantly improved the sensitivity of nitrogen dioxide (NO2) sensing. The surface morphology of the deposited films revealed a distribution that varied with increasing Eu2O3 content. In contrast, the sample with a 7 wt% Eu2O3 content showed a narrower particle size distribution and more homogeneous particle growth on the sensor surface, which in turn demonstrated the highest sensitivity among the prepared samples. The thickness of the deposited films increased with increasing Eu2O3 mixing ratios, while a slight dip in thickness was observed for the sample combined with 5 wt% Eu2O3. Sensitivity results of the developed films against varying NO2 concentrations demonstrated that the optimum operating temperature was 200°C. The SnO2 mixed with 7 wt% Eu2O3 revealed the highest sensitivity (626%) at 120 ppm, with a response time of 10 seconds and a recovery time of 12 seconds. Eu2O3 mixing holds promise for enhancing the sensor properties of SnO2 by modifying its nanostructure and surface morphology, improving the oxygen vacancy concentrations, and increasing sensitivity under various environmental conditions.
Keywords
Gas sensing; NO2; Rare–earth elements; Structural properties; Surface morphology

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