Microflow Manipulation by Velocity Field Gradient: Spontaneous Patterning of Silver Nanowires for Tailored Flexible Transparent Conductors

Abstract

Flexible transparent conductors (TCs) are the fundamental components for emerging soft optoelectronics because of their excellent optical, electrical, and mechanical properties. These properties are attributed to reasonable alignment of conductive functional nanomaterials, especially 1D inorganic nanowires. Although various patterning technologies are proposed, patterning highly transparent conductors with satisfactory conductivity and flexibility in a facile, scalable, and versatile manner remains an open issue. Here, a directed self‐assembly strategy is presented for patterning silver nanowires (AgNWs) into flexible TCs with a cross‐linked network structure using microflow velocity‐field‐induced alignment at a liquid–solid interface. Under dual‐surface architectonics, the periodically varying internal microflow in the overcoated AgNW suspension facilitates the spontaneous alignment of the AgNWs on the designated regions in a layer‐by‐layer manner, yielding highly ordered AgNW TCs with an ultrahigh transmittance (98.2%), low sheet resistance (29.7 Ω sq−1), and prominent mechanical deformability. The proposed strategy is further applied to fabricate high‐accuracy arbitrary AgNW circuits to realize flexible transparent heaters with adjustable localized heat sources. This is a universal and customizable method for producing functional nanomaterials with hardly any scale or shape limitations in a streamlined fashion and provides great freedom for prototyping and manufacturing high‐performance soft optoelectronics.