Ethanol concentration sensor based on TiO2-ZnO composite film enhanced surface plasmon resonance with a molybdenum disulfide-graphene oxide hybrid nano-sheet

Abstract

A method of ethanol concentration detection based on surface plasmon resonance is proposed. Therefore, a novel prism coupling structure is designed for the ethanol concentration sensor by use of the unique feature of graphene oxide (GO) to act as a sieve for ethanol in water, and a TiO2-ZnO composite film is chosen to enhance the surface plasmon resonance with a molybdenum disulfide–graphene oxide hybrid nano-sheet. The thickness of each layer of the structure is analyzed by the finite element method to obtain the optimal value in order to improve the sensitivity greatly. The optimal thickness of each layer is given, and the sensitivity of the surface plasmon resonance ethanol concentration sensor can reach as high as 0.089°/% within the detection range of ethanol concentration (0%–80%). The relationship between the surface plasmon resonance angle and the ethanol concentration is obtained within the detection range of ethanol concentration.