Análisis de factibilidad de la fabricación de sensores mediante nanotubos de carbono sintetizados por CVD

Abstract

This research project arose from the need to propose alternatives to the conventional materials with which the indispensable sensors for small and large-scale industries are manufactured. Due to the increasing demands on precision and reliability and the inherent cost of high-quality materials, we sought to test the feasibility of carbon nanotubes synthesized based on commercial materials and easy access to register changes in flexibility, presence of gas, and temperature. The main objective was to synthesize carbon nanotubes by chemical vapor deposition using acetylene as precursor gas and copper and nickel oxide as catalysts and analyze the product to determine whether or not its use in the manufacture of said sensors is feasible. Considering the relevance of precision, the number of layers, purity, morphology, and distribution that the synthesized carbon nanotubes must have were determined to be able to perform the sensors' calibration. To determine these properties, the product of the experiments carried out with the different proposed configurations was characterized using Raman spectroscopy and scanning electron microscope (SEM) techniques. The methodology allowed us to determine how the condition of the catalysts affects the type, morphology, and purity of the carbon nanotubes produced in the synthesis. The analyses indicated that multilayer carbon nanotubes with forest-type morphology were synthesized using commercial nickel foil treated with chemical agents through sonication. It was concluded that this type of morphology and carbon nanotube, according to its layers, is unsuitable for sensing changes in temperature, flexibility, or the presence of gases. Still, it is an appropriate material for manufacturing the sensor structure by applying it to a polymeric matrix.