Simple, universally adaptable techniques for fabricating nanostructured films are required to translate lab scale innovations into low-cost solutions for the developing world. Silver nanowires have emerged as an attractive building block for fabricating a wide range of sensors and devices. Herein, we report the in situ formation of conductive silver-nanowire networks on paper, thereby, eliminating the need for either cost-intensive ink formulation or substrate preparation or complex post-deposition sintering steps. Reminiscent of the photographic process of ‘salt printing’, a desktop office printer was used to deposit desired patterns of silver bromide on paper/plastic substrates, which were subsequently overexposed to light from a halogen lamp and then immersed in a photographic developer. Percolating networks of silver nanowires (30-100 nm dia. and 1-2 µm length) that conformally coated the substrate were formed. Thus, films of silver nanowires can be fabricated over large areas at a low-cost by combining two widely used processes—inkjet printing and photographic development. These films show excellent performance characteristics as strain gauges and as SERS (Surface Enhanced Raman Spectroscopy) substrates.
