Evaluation of Indium Tin Oxide for Gas Sensing Applications: Adsorption/Desorption and Electrical Conductivity Studies on Powders and Thick Films

Abstract

By combining results of adsorption/desorption measurements on powders and electrical conductivity studies on thick and thin films, the interaction of indium tin oxide with various ambient gas species and carbon monoxide as potential target gas was studied between room temperature and 700 °C. The results show that the indium tin oxide surfaces exhibit a significant coverage of water-related and carbonaceous adsorbates even at temperatures as high as 600 °C. Specifically carbonaceous species, which are also produced under carbon monoxide exposure, show a detrimental effect on oxygen adsorption and may impair the film’s sensitivity to a variety of target gases if the material is used in gas sensing applications. Consequently, the operating temperature of an ITO based chemoresistive carbon monoxide sensor should be selected within a range where the decomposition and desorption of these species proceeds rapidly, while the surface oxygen coverage is still high enough to provide ample species for target gas interaction.

Instrumentação para medidas de mobilidade eletrônica e concentração de portadores em amostras semicondutoras, pelo método de van der Pauw

“…Além disso, os dados são salvos em arquivos de dados, para análise posterior. Nesse trabalho apresentaremos os resultados para a medida de uma amostra Indium tin oxide (ITO) (Dietrich et. al.…”

Compact and efficient lossy mode resonant refractive index sensor for aqueous environment

“…Transparent conducting oxide thin films and particularly indium-tin-oxide (ITO) films find their applications in integrated touch sensors for flexible OLED displays, photovoltaic cells, LCDs, optical fiber sensor, gas sensing, analysis of ionized media and opto-electrochemical label free biosensors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. ITO films are transparent, conducting and chemically stable and can be used for integrated-optic sensing applications.…”

Structural, Optical, and Sensing Properties of Nb-Doped ITO Thin Films Deposited by the Sol–Gel Method

“…Consequently, CO detection is necessary because of its odorless and colorless properties [ 52 , 53 ]. Over time, researchers have studied metal-oxides based systems, such as SnO 2 , In 2 O 3 , ZnO [ 8 , 54 ], and indium-tin oxide (ITO) [ 55 , 56 ], with the aim to develop CO sensors. According to scientific reports, the properties of ITO thin films can be tailored by doping with various metals: Ag [ 57 ], Ga [ 58 ], Cr [ 59 ], Zn [ 30 , 60 ], Ti [ 61 ], Nb [ 62 ], and so on.…”