Light-Induced Nanowetting: Erasable and Rewritable Polymer Nanoarrays via Solid-to-Liquid Transitions.

Template wetting methods have been widely applied in the preparation of one-dimensional (1D) polymer nanomaterials. The pattern control using the template wetting methods, however, still remains a great challenge, mainly due to the nonselectivity of the polymers toward the environmental triggering. In this work, we present a facile light-induced nanowetting (LIN) method to fabricate patterned nanoarrays using anodic aluminum oxide (AAO) templates. Photoresponsive azobenzene-containing polymers (azopolymers) that exhibit light-induced reversible solid-to-liquid transitions are used. Upon exposure to ultraviolet lights, the azopolymer chains can wet the nanopores of the AAO templates in a liquid state via capillary force. The azopolymer chains are then solidified by illuminating them with visible lights, resulting in the formation of azopolymer nanoarrays. Notably, using designed photomasks, the patterns of the nanoarrays can be ingeniously controlled with the characteristic of erasable and rewritable nanostructures.