摘要
运用密度泛函理论中的杂化泛函B3LYP研究了高效太阳能电池新型染料敏化剂JK16和JK17的几何结构、电子结构、极化率和超极化率,并用含时密度泛函理论(TDDFT)研究了电子吸收谱.基于含时密度泛函理论计算结果和实验结果的定性符合,指认了在可见和近紫外区的吸收属于π→π*跃迁.计算结果还表明JK16和JK17激发能最低的三个跃迁都与光诱导电荷转移过程有关,而且二-二甲基芴氨基苯并噻吩基团对光电转换过程的敏化起主要作用,发生于染料敏化剂JK16、JK17和TiO2界面之间的电荷转移是由染料分子激发态向半导体导带的电子注入过程.此外,通过对JK16和JK17的比较,分析了亚乙烯基对几何结构、电子结构和谱学特性的影响.
The geometries, electronic structures, polarizabilities, and hyperpolarizabilities of novel organic dye sensitizers JK16 and JK17 were studied by density functional theory （DPT） using the hybrid functional B3LYP. Ultraviolet-visible （UV-Vis） spectra were investigated by time dependent DFT （TDDPT）. Features of the electronic absorption spectra in the visible and near-UV regions were assigned based on a qualitative agreement between TDDFF calculations and experiments. The absorption bands are assigned to π→π^＊ transitions. Calculated results suggest that the three excited states with the lowest excited energies in JK16 and JK17 are due to photoinduced electron transfer processes. The dimethylfluorenyl amino benzo [b] thiophene groups are the main chromophores that contribute toward the sensitization of photo-to-current conversion processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizers JK16 and JK17 is due to an electron injection process from excited dyes to the semiconductor＇s conduction band. The role of vinylene in geometries, electronic structures, and spectral properties were analyzed in a comparative study ofJK16 and JK17.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2009年第1期53-60,共8页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(10647006)
兰州理工大学优秀青年基金(Q200704)
兰州理工大学科研发展基金资助项目
关键词
染料敏化剂
电子结构
密度泛函理论
吸收谱
Dye sensitizer
Electronic structure
Density functional theory
Absorption spectrum
