Networks of metallic nanowires are promising candidates for transparent and flexible electrodes, as alternatives to metal oxide based electrodes such as indium tin oxide (ITO). Such nanowire electrodes can have excellent performance, however, the mechanical and chemical stability of the electrodes are usually week. Here, we report a simple method for fabricating transparent and flexible gold electrodes that have excellent mechanical and chemical stability. Gold nanoparticles were synthesized and subsequently aggregated by adding sodium hydroxide into the solution. The aggregated nanoparticles were deposited on a polycarbonate (PC) filter membrane followed by flash light sintering (FLS). By using this method, transparent and flexible gold electrodes were produced, with electric properties found to be stable under mechanical treatment such as folding, peeling and rubbing and under chemical treatment such as water, ethanol, nitric acid and sodium hydroxide. A nanosecond pulsed (7-9 ns), solid state laser (SSL) at 355 nm coupled to a galvo-scanning mirror system was used for laser assisted processing (patterning and ablation) of the gold nanoparticle thin films to further increase the transparency. By careful evaluation of laser (pulse energy, repetition rate etc.) and scanning parameters (speed, pitch etc.) a resolution better than 10 um could be realized by this laser scanning system, which are used to optimize the transmission and conductivity of the FLS gold nanoparticle layer. It is found that this method have potential to produce mechanically and chemically stable electrodes with transmittance over 90% and sheet resistance less than 100 Ohm/sq.
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