Liquid Assembly of Floating Nanomaterial Sheets for Transparent Electronics

Jürgen Brugger, Zongming Su, Shao-Chi Yu, Xiao Sheng Zhang
2019
Article

Résumé

A novel pattern strategy of a nanomaterial network that can self‐assemble onto prepatterned soft substrate to realize ultra‐transparent electronics is presented. The approach detailed is based on the combination of nanomaterials' self‐assembly at the water–air interface to form nanomaterial networks and the breakage phenomenon of water–nanomaterial membranes to form designed patterns. With the comprehensive investigation of this phenomenon, nanomaterial networks are manipulated to attach to prepatterned sidewalls. This leads to a remarkable transparency improvement without conductive property decline. Three 1D nanomaterials with various geometries are demonstrated to verify the universal feature of this pattern strategy, including silver nanowire (AgNW), carbon nanotube, and zinc oxide nanowire. Furthermore, sequential layer‐by‐layer deposition of several 1D nanomaterials has also been demonstrated by using the proposed approach, revealing an attractive potential of multiple‐junction transparent electronics. The fabricated micro‐grid structure of AgNWs with a line width of 5 µm and pitch of 150 µm has a sheet resistance of 37.88 Ω sq−1 and an optical transmittance of 86.06%. This fabrication strategy opens up opportunities for different nanomaterials in many transparent and wearable applications.

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https://infoscience.epfl.ch/record/269299?ln=fr

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