Dynamic Agitation-Induced Centrifugal Purification of Nanowires Enabling Transparent Electrodes with 99.2% Transmittance

To promote silver nanowire (AgNW) as a viable commercial alternative for transparent electrodes, it is necessary to further develop industrially scalable, high-performance yielding and cost-efficient methods of purifying large quantities of as-prepared AgNW suspensions. In this work, a facile, effective, and mass scalable purification method that employs a novel dynamic agitation-induced centrifugal filtration concept to obtain highly purified and printable AgNW solutions. This unique dynamic filtration system, which amalgamates the advantages of membrane filtration, centrifugal filtration and cross-flow filtration, is effective at (1) removing nanoparticles, short nanorods and organic additives from as-prepared AgNW suspensions without producing aggregation; (2) concentrating purified AgNW suspensions to a desirable concentration; and (3) formulating printable AgNW suspensions with suitable solvents. The resulting purified, polyol-method synthesized AgNW with a modest aspect ratio of approximate to 1000 and narrowed length distribution, can be coated into flexible transparent electrodes to yield a transmittance of 99.2% and 95.2% at 230 and 29.6 ohm sq(-1) respectively. These performance metrics are comparable or exceed that of most transparent electrodes made from AgNW with larger aspect ratio (>2000) but purified through conventional purification methods. To maximize the dynamic purification efficiency, a model is also developed to describe and predict this dynamic filtration process.