Spray Deposition of Silver Nanowires on Large Area Substrates for Transparent Electrodes

The most promising materials to replace indium tin oxide (ITO) in transparent electrodes could be silver nanowires. One of the challenges is, however, the large-scale deposition of silver nanowires. This study provides a solution to deposit silver nanowires on large substrate area by spray deposition. The new concept is to spray on a heated glass substrate in vertical position with a flat spray beam instead of the basic conic beam. After optimization of the spray parameters such as the substrate cleaning, the droplets size, the pressure, and the spray distance, a surface of 100 cm2 was fully covered with a very good homogeneity, and it was demonstrated that the concept can be extended on a much higher substrate area. The electrical and the optical properties of such a large sample were investigated by sheet resistance, transmittance, and haze factor measurements. A silver nanowire network with a sheet resistance of 9 Ω/sq, a visible transmittance of 91.7%, and a haze factor of 3.7% was deposited for a spray time of only 3 min for the 100 cm2 area. The trade-off sheet resistance/haze factor showed similar and even better results than the ones published in the literature for smaller substrate area coverage by using other methods of deposition.