Disolution Of Copper Phthalocyanine And Fabrication Of Its Nano-Structure Films

The mono-protonated [CuPc·H]+ and di-protonated [CuPc·H2]2+ forms of copper phthalocyanine( CuPc) were obtained by increasing concentrations of trifluoroacetic acid (TFA) solution to a fixed concentration of CuPc solutions. UV-Vis specrum shows that the Q bands of these two derivatives split and shift to the red, which means successive protonation happened and caused the two derivatives to lose their symmetry. The protonation of CuPc is reversible which has requirement to the protonic acid concentration. The concentration of protonic acid which needed to effect protonation increased linearly with solvent basicity. The less basic solvents encourage protonation more than the more basic solvents. After the protonation step, the solubility of protonated CuPc in nitromethane increases 60 times. The CuPc film was fabricated by the electrophoretic deposition (EPD) method from the protonated CuPc dissolved in nitromethane containing TFA with ITO glass and platinum plate working as cathode and anode electrodes respectively. Several CuPc films with different structure and size were fabricated by changing the applied voltage, deposition time, concentration and temperature of CuPc solution which were detected by Scanning electron microscope (SEM), UV-Vis specrum shows that CuPc films fabricated with more applied voltage, deposition time and concentration of CuPc solution had stronger UV absorption, while CuPc film fabricated with higher temperature of CuPc solution had lower absorption. Futhermore, the CuPc film fabricated with untreated ITO glass is inαphase, the 2θpeak is at 6.819°, corresponding to the interplanar space (d) of 12.950A , stacking direction (b-axis) was parallel to the substrate, which were detected by X-ray diffraction, however when the ITO substrate dipped in coupling agents, the CuPc films fabricated on the treated ITO substrates were inβphase and the structure were changed.