Abstract:
As one of the quasi-zero-dimensional materials, 60fullerene (C
60) and its organic/polymeric derivatives exhibit great application potential in many high-technology fields due to their outstanding optical, electronic, optoelectronic and magnetic properties. A new triphenylamine-fluorene copolymer-60fullerene covalently bridged triad (C
60-PTF-C
60) was synthesized by the 1,3-dipole addition reaction of C
60, sarcosine and PTF terminated with two aldehyde groups (CHO-PTF-CHO). This material, which was highly soluble in some common organic solvents, was embedded into an optically nonactive transparent poly(methylmethlacrylate) (PMMA) matrix to produce the PMMA-based C
60-PTF-C
60 film for nonlinear optics. The nonlinear optical (NLO) and optical limiting (OL) properties of C
60-PTF-C
60 were investigated through an open-aperture Z-scan setup at 532 nm.The C
60-PTF-C
60/PMMA film exhibited more excellent NLO and OL responses when compared to the C
60/PMMA film under the same experimental conditions due to photo-induced electron transfer between C
60 and PTF in the copolymer structure. The achieved nonlinear coefficient (
βeff), imaginary third-order susceptibility (Imχ
(3)), and OL threshold were 437.75 cm/GW, 1.87×10
−10 esu, and 0.34 GW/cm
2, respectively. For comparison purpose, the corresponding
βeff, Imχ
(3), and limiting threshold of the C
60/PMMA film were 188.87 cm/GW, 0.81×10
−10 esu, and 0.53 GW/cm
2, respectively.