Selective infrared emitters based on randomly oriented silver nanowires

We investigated randomly oriented silver nanowires films deposited onto different substrates for infrared emission reduction in the long-wavelength range, i.e. 8-12 μm. For this aim we prepared a set of films differing in both metallic nanowires' dimensions, length and diameter, as well as metal content. Several films were prepared by drop-casting from density-controlled solutions and then characterized by scanning electron micrography. Following this preliminary characterization, the metal filling factor for each film was retrieved using a software based on visual method. All samples were then placed onto a heating holder and their temperature evolution was monitored with a focal plane array (FPA) infrared camera, in order to characterize their infrared emission in the long infrared range. Experimental results show that the combination of wire diameter and metal filling factor may affect the infrared emission of the resulting mesh, making these coatings suitable for infrared signature reduction applications. ©Società Italiana di Fisica.