四溴-2,3-萘酞菁铅的合成及性质研究

Synthesis and Properties of Tetrabromo-2,3-naphthalocyanine Lead(Ⅱ)

以 1 ,8 -二氮杂双环 [5 .4 .0 ]+ -碳烯 -7(DBU)为催化剂合成了中心原子为重原子铅、环取代基为重原子溴的萘酞菁配合物四溴 -2 ,3-萘酞菁铅 [Pb Nc Br4],并研究了该配合物的电子吸收光谱、热稳定性、光限幅特性及重原子对其光限幅特性的影响及其机理 .该配合物在近红外区 (795～ 82 5 nm)有强吸收 (Q带 ) ,溴取代可使配合物 Q带略微蓝移 ,溶剂的极性对配合物的电子吸收光谱有较大影响 .该配合物具有较高的热稳定性 ,气氛对其热稳定性有明显影响 ,其在 N2 气氛中的热稳定性明显比在 O2 气氛中的高 ;在 O2 气氛中为一步分解 ,在 N2 气氛中为多步分解 .标题配合物具有优异的非线性光限幅特性 ,在高线性透射率 88%时的限幅阈值为 1 4 8m J/ cm2 ,限幅幅值为 332 m J/ cm2 ,损伤阈值约为 3J/ cm2 ,其光限幅特性明显优于光限幅新材料 C60 (透射率 70 %时 ,限幅阈值大于 2 4 0 m J/ cm2 ) .重原子铅和溴可显著优化材料的非线性光限幅特性 .

Tetrabromo-2,3-naphthalocyanine lead(PbNcBr 4) was synthesized in the presence of 1, 8-diazabicycloundec-7-ene(DBU) and its electronic absorption spectra, thermal stability, optical limiting property and the effect of bromine substituent on the above properties were investigated. There is one strong Q-absorption band in nearinfrared region. Bromine substituent attached to outer Nc ring results in the Q-band of PbNcBr 4 shifting to the blue compared to the complex unsubstituted. The polarity of solvents have influences on the electronic absorption spectra greatly. The complex shows high thermal stabilities and appears to be more stable in N 2(the onset temperature 504.6 ℃) than in O 2(the onset temperature 326.8 ℃). The thermal stabilities decrease on account of bromine substituent attached to outer Nc ring and declining extent changes with the varieties of atmosphere(decreased by 175 ℃ in N 2, 25 ℃ in O 2). Decomposition mechanisms differ according to the varieties of atmosphere with one step in O 2 and multi steps in N 2. At a relatively high linear transmittance of 88%, the limiting threshold is 148 mJ/cm 2, the clamped fluence is 332 mJ/cm 2, and the damage fluence is about 3 J/cm 2. The optical limiting behavior of PbNcBr 4 is better than that of C 60 whose limiting threshold is above 240 mJ/cm 2 with a linear transmittance of 70%. It can be regarded as a new kind of materials which has a better optical limiting property.