Infrared, transient thermal, and electrical properties of silver nanowire thin films for transparent heaters and energy-efficient coatings

n this study, we investigate the infrared and electrical propertiesas well as the thermal response of transparent silvernanowire (AgNW) based thin-film heaters, when subjected toJoule heating. Controlling the number of layers and hence thedeposition time, our spray-coating technique allows to modulatethe thermal and electrical properties of the thin films in a precisemanner. In addition, this technique enables the fabrication ofhomogeneous and large-area heaters, which, in terms of theirelectro-optical properties, nicely compare to the performances ofstate-of-the-art AgNW transparent electrodes. The thermal response and the electrical properties are accurately reproducedby a purposely developed physical model, which shows that thetemperature dependence of the AgNW film resistance is loweredby a factor of 2 compared to bulk silver, independently of thenumber of deposited layers. Compared to uncoated glass,the emissivity decreases by 58% at a coverage rate of 58%. At thesame time, the AgNW film can sustain a transparency as high as81.3%. Therefore, AgNW-based thin films can be used as a low-emissivity coating, for e.g., energy-efficient window glazingapplications. Finally, we accurately determine the fragmentationtemperature of AgNWs, which sets the ultimate limitation of usefor heating applications.