SYNTHESIS AND STUDY OF GAS-SENSITIVE NANOSTRUCTURES OF THE Zn-Sn-O SYSTEM

Наностержни оксида цинка синтезированы гидротермальным методом. Проведена обработка полученных образцов в водно-спиртовом растворе станната калия и мочевины при 170°С в течение 30 и 60 минут. В результате получены наноструктуры Zn - Sn - O. Химический состав поверхности образцов ZnO и Zn - Sn - O исследован с помощью рентгеновской фотоэлектронной спектроскопии. Проанализирована их чувствительность к парам изопропилового спирта (1000 мд) при температурах 120 °С, 180°С, 250 °С. Показано перераспределение электронной плотности при формировании композитных наноструктур Zn - Sn - O, проявляющееся в химическом сдвиге пиков O1s и Zn2p. Это свидетельствует о перестроении химических связей при замещении атомов цинка оловом. Обнаружено, что чувствительность композитных структур к парам изопропилового спирта значительно превышает чувствительность ZnO во всем исследуемом температурном диапазоне. Улучшение газочувствительных свойств связано с наличием в образцах системы Zn - Sn - O поверхностных центров различного типа, принимающих участие в адсорбции и окислении изопропилового спирта. Zinc oxide nanorods were synthesized by the hydrothermal method. The obtained samples were processed in an aqueous-alcohol solution of potassium stannate and urea at 170 °C during different times. As a result, Zn - Sn - O nanostructures were obtained. The surface chemical composition of ZnO and Zn - Sn - O was studied using the X-ray photoelectron spectroscopy. Its sensitivity to vapors of isopropyl alcohol (1000 ppm) at 120 °C, 180 °C, 250 °C was analyzed. The electron density redistribution during the Zn - Sn - O composite nanostructures formation manifests itself in the chemical shift of the O1s and Zn2p peaks. It confirm the rearrangement of chemical bonds when zinc atoms are replaced by tin ones. It was found that the sensitivity of composite structures to isopropyl alcohol vapors significantly exceeds that of ZnO in the entire temperature range under study. The improvement of gas-sensitive properties is associated with the presence of various types of surface centers in the Zn - Sn - O samples that participate in the adsorption and oxidation of isopropyl alcohol.

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Influence of silver electrochemically deposited onto zinc oxide seed nanoparticles on the photoelectrochemical performance of zinc oxide nanorod films

Nanomaterials and Nanotechnology ◽

10.1177/1847980419844363 ◽

2019 ◽

Vol 9 ◽

pp. 184798041984436 ◽

Cited By ~ 2

Author(s):

Alejandro Aranda ◽

Richard Landers ◽

Patricio Carnelli ◽

Roberto Candal ◽

Hugo Alarcón ◽

...

Keyword(s):

Zinc Oxide ◽

Silver Nanoparticle ◽

Photoelectron Spectroscopy ◽

Zinc Oxide Nanorods ◽

Oxide Glass ◽

Photoelectrochemical Performance ◽

X Ray ◽

Heat Treated ◽

Oxide Nanorods ◽

Electrochemically Deposited

The present article examines the synthesis and characterization of zinc oxide nanorods grown on zinc oxide and silver nanoparticle seeds. Zinc oxide seeds were electrodeposited on a support of fluorine-doped tin oxide glass and heat-treated at 380°C. Silver nanoparticles were then deposited on this substrate, which was heat-treated at 160°C. Their presence was confirmed using ultraviolet–visible spectroscopy, by observing an absorption peak around 400 nm, corresponding to surface plasmon resonance. Growth of zinc oxide nanorods was achieved in a chemical bath at 90°C. The obtained films were analyzed by cyclic voltammetry, X-ray diffraction, and scanning electron microscopy. They consisted of zinc oxide with a Wurtzite-type crystal structure, arranged as nanorods of 50 nm. X-ray photoelectron spectroscopy exhibits peaks attributed to silver (0) and to the formation of silver oxide on the silver nanoparticle surface. In addition, two types of oxygen (O 1 s) were observed: oxygen from the crystalline network (O–2) and chemisorbed oxygen (–OH), for the seed and the nanorod films, respectively. The nanorods grown on zinc oxide seeds with silver deposits had a round shape and greater photoactivity than those grown without silver. This difference is attributed to the additional reflection that silver provides to the light reaching the film, thereby increasing the photogeneration from the charge carriers.

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Исследование формирования слоев станната цинка методом рентгеновской фотоэлектронной спектроскопии

Журнал технической физики ◽

10.21883/jtf.2020.07.49447.276-19 ◽

2020 ◽

Vol 90 (7) ◽

pp. 1132 ◽

Cited By ~ 1

Author(s):

С.С. Налимова ◽

З.В. Шомахов ◽

В.А. Мошников ◽

А.А. Бобков ◽

А.А. Рябко ◽

...

Keyword(s):

Zinc Oxide ◽

Hydrothermal Method ◽

Gas Sensors ◽

Photoelectron Spectroscopy ◽

Zinc Oxide Nanorods ◽

Transparent Electronics ◽

Synthesis Time ◽

Zinc Stannate ◽

X Ray ◽

Oxide Nanorods

The features of the formation of zinc stannate nanostructures are considered that are of interest for gas sensors, solar energy and conducting transparent electronics. The samples were obtained by hydrothermal method using zinc oxide nanorods as a template with the variation of synthesis time and investigated by X-ray photoelectron spectroscopy. It is shown that this method can be used to analyze the formation of zinc stannate.

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X-ray Photoelectron Spectroscopy of Surface Layers of Faceted Zinc Oxide Nanorods

Proceedings of Universities ELECTRONICS ◽

10.24151/1561-5405-2021-26-6-481-490 ◽

2021 ◽

Vol 26 (6) ◽

pp. 481-490

Author(s):

Z.V. Shomakhov ◽

◽

S.S. Nalimova ◽

A.A. Bobkov ◽

V.A. Moshnikov ◽

...

Keyword(s):

Zinc Oxide ◽

Binding Energy ◽

Photoelectron Spectroscopy ◽

Photoelectron Spectra ◽

Zinc Oxide Nanorods ◽

Hydroxyl Groups ◽

Surface Layers ◽

Defective Structure ◽

X Ray ◽

Oxide Nanorods

The control of the nanomaterials surface’s hydrophilic properties is of interest for various applications, including optics, photocatalysis, and spintronics. In this work, techniques for designing the defective structure of the surface layers of faceted zinc oxide nanorods during sacrificial doping with iodine by hydrothermal synthesis were considered. The features of the chemical composition of the surface of the obtained layers were studied using X-ray photoelectron spectroscopy (XPS). It was found that peaks corresponding to the binding energy of iodine were not observed in the X-ray photoelectron spectra. An additional peak with a binding energy of 531.8 eV, corresponding to the oxygen of OH groups, was observed in the O 1s level spectrum for zinc oxide nanorods doped with iodine. During the heat treatment of the synthesized layers, iodine evaporates, which leads to a change in the surface composition and an increase in the oxygen content of the surface hydroxyl groups. A model has been proposed to explain the experimental results. It has been established that XPS techniques are effective for analyzing the defective surface structure of functional layers based on faceted zinc oxide nanorods.

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