1D, 2D, and 3D Micropatterning of ZnO Nanoparticles and Nanorods by Two‐Photon Polymerization and Surface Functionalization

Abstract In this paper, a novel method is proposed for selective deposition of ZnO nanoparticles (NPs) and growth of ZnO Nanorods (NRs) on multi‐dimensional patterned polymer surfaces. The method involves microfabrication of functionalized 1D, 2D, and 3D polymer structures by two‐photon polymerization (TPP) followed by selective assembly of ZnO NPs acting as seeds before growing ZnO NRs by chemical bath deposition (CBD) technique at low temperature. The immobilization of the ZnO NPs seed layer is done by electrostatic interaction between the positively charged polymer surface functionalized by amine groups and the negatively charged ZnO NPs functionalized by citrate molecules. The influence of citrate molecules on the stability of the ZnO NPs dispersions and their immobilization on the polymer surface is demonstrated. Spatially controlled and selective growth of ZnO NRs is shown at low temperatures on multi‐dimensional structures up to 9 mm ² and having different shapes, including 1D polymer lines, 2D microplates, and 3D arrays of cones. The diameter of NRs and their orientation can be controlled through the size of ZnO NPs and the shape of the polymer structure respectively.