摘要
通过电场诱导表面光电压谱确定外围缩合4个1,10-啡啉单元的氮杂酞菁为p型有机半导体,并对各个谱带进行合理的归属.结果发现,Soret带长波侧光电压曲线在电场作用下轻微蓝移,根据电场对高极化度n轨道基态的影响,将其归属为n-π*跃迁.这一结果表明,光电属性与材料的分子结构和电子结构密切相关,为设计有机半导体模型提供了进一步的实验数据.
In this paper an aza H_2Pc containing four 1,10-phenanthroline subunits was presented and its photoluminescence and photovoltage properties were investigated. For the same kind of electronic transition(π-π~* transition), the photoluminescence and photovoltage exhibit competitive mechanism. Interestingly, the Soret-band SPV response is stronger than that of Q-band due to the four peripheral subunits. Based on the electric-field-induced surface photovoltage spectroscopy, the conduction type of the expanded aza H_2Pc was judged to be p-type. This contribution from the peripheral electron-withdrawing subunits comes with decreasing the electron-filling energy and facilitating the molecular oxidation. From the similar behavior, the Q-band and short wavelength side of Soret-band were assigned to π-π~* transition. Another intriguing aspect is that the long wavelength side of Soret-band exhibits a slight blue shift in the external electric field. According to the influence of electric field on the ground state of n-orbital with a high polarizability, it was assigned to n-π~* transition. The results indicate that the optoelectronic properties closely related to the molecular structure and the electronic structure, which provide further experimental data for developing an organic semiconductor model.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第7期1294-1297,M006,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:60307002)资助
