Nonlinear optical performances of graphene oxide ternary nanohybrids functionalized by axially coordinated gallium porphyrins

Abstract

Graphene oxide (GO) ternary nanohybrids functionalized by axially coordinated gallium porphyrins have been prepared, and characterized by various spectroscopic techniques. The Z-scan experimental results show that the GaTPP-GO-GaTTP ternary nanohybrid possesses enhanced nonlinear optical properties in comparison with GO, gallium porphyrins and two other binary nanohybrids (GaTPP-GO and GaTTP-GO) under 4 ns laser pulses, which is ascribed to a combination of mechanisms. The different types of porphyrins as a major factor have a significant effect on the photophysical and nonlinear optical (including optical limiting) performances of the as-prepared nanohybrids. By adjusting the types of porphyrins grafted onto GO, the optical nonlinearity can be precisely tuned. The role of considerable electronic interactions and charge transfer in the nonlinear optical performance of GaTPP-GO-GaTTP was clarified by using the UV/vis absorption, fluorescence, Raman, transient photocurrent and electrochemical impedance spectroscopy techniques.