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使用密度泛函理论(DFT)和含时密度泛函理论(TDDFT)以及自然键轨道(NBO)分析,设计比有机染料D5更优秀的用于染料敏化太阳能电池(DSSC)的D5同类物分子.在D5骨架的给电子基团上对称地引入给电子基(—OH,—NH2,—OCH3),既可以使分子的最低未占据分子轨道(LUMO)能级提高,又可以使吸收光谱红移,从而既提高染料分子捕获太阳辐射光子的能力,又提高由染料分子的激发态向TiO2电极注入电子的驱动力.在D5分子的骨架上,对称地引入受电子基(—CF3,—F,—CN),可以使染料分子的吸收光谱强烈地红移,从而更有效地利用太阳能.由LUMO能级的提高和吸收光谱的红移来考虑,所设计的D516,D536,D537分子是比D5优秀的同类物分子,其中D516是最好的.单从吸收光谱红移来考虑,所设计的D565,D567,D568分子是比D5优秀的同类物分子,其中D565的吸收光谱有望与太阳辐射光谱更好地匹配.挑选出来的这6种D5同类物分子都是D-π-A(电子给体-共轭π桥-电子受体)结构.这几种分子的光激发引起的最高占据分子轨道(HOMOs)到LUMOs的跃迁是π-π*跃迁,是分子内电荷转移,吸收光谱是电子吸收光谱,位于近紫外-可见光区.D516和D565有望成为比D5更优秀的用于DSSC的非金属有机染料分子.
D5 congener molecules for dye-sensitized solar cells (DSSCs) that are superior to organic dye D5 are designed using density functional theory (DFT) and time-dependent density functional theory (TDDFT) and natural bond orbital (NBO) The introduction of electron donating groups (-OH, -NH2, -OCH3) symmetrically on the electron donating groups of the D5 backbone not only increases the lowest unoccupied molecular orbital (LUMO) energy level of the molecule but also enhances the absorption spectra of red So as to increase the ability of the dye molecules to capture solar radiation photons and increase the driving force of injecting electrons from the excited state of the dye molecules into the TiO2 electrode. In the framework of the D5 molecule, electron acceptor groups (-CF3, -F , -CN), the absorption spectrum of dye molecules can be strongly redshifted so that the solar energy can be utilized more effectively.D516, D536 and D537 molecules are designed with the increase of LUMO energy level and the red shift of the absorption spectrum D5 excellent congener molecules, of which D516 is the best.On the red shift from the absorption spectrum to consider, the design of the D565, D567, D568 molecule is D5 excellent congener molecules, of which the D565 absorption spectrum is expected with the solar radiation The spectrum is better matched. The six D5s are picked out The species molecules are D-π-A (electron donor-conjugated π-bridge - electron acceptor) structures. The transition from the highest occupied molecular orbital (HOMOs) to the LUMOs due to photoexcitation of these molecules is π-π * Transitions are intramolecular charge transfer, absorption spectra are electron absorption spectra in the near UV-Visible region, and D516 and D565 are expected to be better non-metal organic dye molecules for DSSC than D5.