Improving the electrical and thermal properties of silver nanowire transparent heater via the sputter coating of indium tin oxide

Abstract Transparent heaters (THs) based on silver nanowires (AgNWs) often encounter issues related to the high resistance at the junctions between the wires, resulting in localised high Joule-heating temperatures that can lead to the breakdown of the AgNWs. In this work, an indium tin oxide (ITO) layer was sputter coated onto AgNWs to enhance their electrical and thermal properties. The bare AgNW network exhibited a high sheet resistance of approximately 205.43 Ω/□. After ITO sputtering, the sheet resistance decreased sharply from 205.43 Ω/□ to 30.17 Ω/□, and the transmittance at a wavelength of 550 nm slightly decreased from 93.01% to 84.21%. The optimal performance of the TH based on ITO-coated AgNWs (AgNWs/ITO) was observed at 10 sputtering minutes, showing a sheet resistance of 30.17 Ω/□, a transmittance of 84.21% and a figure of merit of 69.63. The AgNW/ITO TH reached a maximum Joule-heating temperature of 250.9 °C at 11 V, which was 157 °C higher than that of the bare AgNW TH, and exhibited a more uniform heat distribution. During hot plate testing, the thermal stability of the AgNW/ITO TH improved by 140 °C compared with that of the bare AgNW TH. These results demonstrate that AgNWs/ITO have excellent potential for TH applications.