Hierarchical multicolor nano-pixel matrices formed by coordinating luminescent metal ions to a conjugated poly(4'-octyl-2',6'-bispyrazoyl pyridine) film via contact printing

We introduce a cost-effective, yet feasible reactive printing approach namely, "coordination chemistry at the conjugated ligand polymer surface". By using a contact printing technique we selectively fabricated high resolution nano-pixel configurations consisting of red, blue and green (R,G,B) colors arranged in a hierarchical three-dimensional fashion. For this, we have synthesized a novel blue emitting conjugated ligand polymer, [poly(4'-octyl-2',6'-bispyrazoyl pyridine)] (∼ 7-8 KDa) having a tridentate ligand in its repeating unit which forms a thin film prone of binding metal ions. On top of this ligand polymer film, a layer of high-resolution cross-stripes (width ca. 800 nm) was printed comprised of Eu and Tb ions over a large area ∼ 100 × 100 μm². The final woodpile-like assembly produced a new pixel group consisting of B; BG; BR; and BGR (White) colors. The area of the white emitting square is ca. 0.64 μm². The patterned layers that make up the pixels are very thin and thus this new technique might find applications in flexible light emitting devices.