Electrochemical Cross-Linking and Patterning of Nanostructured Polyelectrolyte−Carbazole Precursor Ultrathin Films

Nanostructured ultrathin films of pendant carbazole-modified polyelectrolytes were fabricated using the layer-by-layer deposition technique in order to correlate the importance of highly ordered structures and well-defined layer composition in electrochemical cross-linking and nanopatterning. Both UV−vis and surface plasmon resonance (SPR) spectroscopy studies indicated differences in the film structure and bilayer formation based on the degree of electrostatic interaction and carbazole content. Cyclic voltammetry (CV) and SPR studies confirmed the relationship between film structure and the amount of carbazole units per layer affecting the degree of electrochemical cross-linking. CV in particular was used to determine the mechanism of electron transport and electrochemical cross-linking phenomena. Nanopatterning was demonstrated using current sensing AFM (CS-AFM) in which different applied voltages, writing speeds, and composition of polyelectrolytes were studied together with the formation of a complex nanopattern.