Improved solubility and efficient optical limiting for methacrylate-co-porphyrins covalently functionalized single walled carbon nanotube nanohybrids

To improve the dispersibility of single walled carbon nanotube (SWCNT) in common organic solvents and adjust its photoelectronic performance, two methacrylate-co-porphyrins covalently functionalized SWCNT nanohybrids (SWCNT-TPP 1 and SWCNT-TPP 2) were prepared by radical polymerization. This attachment of porphyrins onto the surface of SWCNT significantly improves their solubility and dispersion stability of the SWCNT-based materials in organic solvents. The electronic interactions between porphyrins and SWCNT were investigated by the UV-vis, fluorescence and Raman spectroscopic methods. Z-scan measurements suggested that both nanohybrids exhibited increased nonlinear absorption and optical limiting performances compared to the separate SWCNT and porphyrins, which can be ascribed to the synergetic effects originating from the charge transfer effect between the two counterparts. The best optical limiting performance is observed for SWCNT-TPP 1 due to more effective charge transfer effect in comparison with those of other samples. These results suggest that the radical polymerization is a useful approach towards the rational design of solution-processible yet stable optical limiting materials, and this concept may be readily extended to other directional optoelectronic properties.