Fabrication and characterization of Ag-Decorated indium–tin-oxide nanoparticle based ethanol sensors using an enhanced electrophoretic method

Abstract

Abstract In this paper different Indium Tin Oxide (ITO)-based ethanol vapor sensors (fabricated as thin films and nanoparticles) are presented, and their structural and sensing properties are investigated. An Electrophoretic Deposition (EPD)-Enhanced method is proposed for the fabrication of pure, and Ag-decorated indium tin oxide sensors. The proposed sensors are then compared to conventional indium tin oxide sensors fabricated by sputtering (thin film), and drop-casting method in terms of response, and working temperature. It is shown that the electrophoretic deposition method has decreased the final particle size of the indium tin oxide nanoparticles by limiting the agglomeration of nanoparticles, and increased the sparsity of the particles forming the sensing material. Results suggest that compared to the conventional sensors, the sensors fabricated by the proposed electrophoretic deposition method (i.e., the pure-indium tin oxide (EPD-TF), and the Ag-decorated indium tin oxide (Ag-EPD) sensors), has considerably better performance for the detection of the ethanol vapors, showing reduced working temperature (110 and 130\xa0°C, respectively), higher response, and better selectivity over CO, methane, methanol, and acetone. Moreover, the response and recovery time of the proposed sensors were found to be lower than most of the previously reported indium tin oxide-based ethanol sensors, approving the positive effect of the electrophoretic method as a simple, controllable method for sensor fabrication.