Synthesis of high aspect ratio silver nanowire precursor by two-step ultrasonic irradiation and its application to transparent conductive film

We investigated a silver carboxylate synthesis method that works by irradiating ethanol containing silver oxide and carboxylic acid in two steps using both low- and high-frequency ultrasonic waves. Specifically, high aspect ratio silver carboxylate samples were synthesized by irradiating ethanol containing silver oxide and carboxylic acid low-frequency ultrasonic waves for a short time and then further irradiating them with high-frequency ultrasonic waves for a longer period of time. The strong physical actions produced by the low-frequency (44 kHz) ultrasonic waves promoted fragmentation and degradation of the produced silver carboxylate particles, while the high-frequency (1.0 MHz) frequency ultrasonic waves promoted the growth of the produced silver carboxylate particles via chemical actions. Using the synthesized precursor, we then succeeded in producing silver nanowire transparent conductive films using a simple process. The film performance improved with higher aspect ratio precursors.