The Influence of Microstructures of Ceramics on the Monitoring of Environmental Humidity

Abstract:

The sensing elements for humidity has been vastly researched to be applied in several areas, since automotive and food industries up to automation in the agricultural production and in the environmental monitoring. In this work, ceramic material are focused, owing to their unique structure, consisting of grains, grain boundaries, surfaces and pores, the control of which allow to obtain suitable microstructure to be used as humidity sensors. In this work, the influence of the relative humidity on the electrical conductivity of the ceramic sensing elements of ZrO₂ and of TiO₂, under specific climatic conditions, is investigated. In this sense, the ceramics used as humidity sensing elements were manufactured through conventional ceramic processing. The sintered ceramics were characterized through X-ray diffractometry techniques, scanning electron microscopy, apparent density by the Archimedes principle and linear retraction. The results showed the development of a solid solution of ZrO₂-TiO₂. The microstructures presented a homogeneous distribution of pores. The ceramic tablets, sintered at 1100 °C, evidenced a linear behaviour in the curves capacitance versus environment humidity.

• Periodical: Materials Science Forum (Volumes 798-799)
• Pages: 713-718
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.798-799.713
• Online since: June 2014
• Authors: Rodrigo de Matos Oliveira*, Maria do Carmo de Andrade Nono, Fernanda Cristina Reis
• Keywords: Environmental Monitoring, Porous Ceramics, Relative Humidity, Sensor Elements

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