Seyednoruziyan Bahareh, Zamanloo Mohammad R, Nasser Shamkhali Amir, Alizadeh Taher, Noruzi Shima, Aslani Shaghayegh
Department of Applied Chemistry, Faculty of Basic Science, University of Mohaghegh Ardabili, Ardabil, Iran.
Department of Applied Chemistry, Faculty of Basic Science, University of Mohaghegh Ardabili, Ardabil, Iran.
Spectrochim Acta A Mol Biomol Spectrosc. 2021 Feb 15;247:119143. doi: 10.1016/j.saa.2020.119143. Epub 2020 Nov 4.
A series of novel azo dyes possessing varying conjugation lengths and different donor moieties, based on 5-amino isophthalic acid were designed and synthesized. Azobenzene unites were utilized as the π-spacer part to extend the conjugation range and connect the donor to acceptor unit. When the dialkylamino substituent was changed from dimethyl to diethanol, a red shift in the absorption spectra and λ was observed. The photophysical and electrochemical properties of the straightforward-synthesized dyes were investigated in solution and on photoanode surface which promised the suitability of the dyes as photosensitizers for dye sensitized solar cells (DSSCs). Increased dye adsorption strength on the TiO surface as well as light harvesting capability was expected due to bearing two anchoring-electron accepting groups which could lead to enhanced electron transfer (ET). The ATR absorption spectra clearly showed that these dyes were adsorbed on the TiO surface. It was realized that increasing π-conjugation length as well as hydroxyl containing donor group gave rise to improved photovoltaic performance of DSSCs. Reduced band gap along with suppressed electron recombination and amended dye regeneration were recognized to play an important role in enhancing performance parameters. DSSCs based on these dyes exhibited higher solar conversion efficiency in comparison with efficiency of other meta azo dyes that were previously synthesized. Theoretical calculations (DFT/TDDFT) expressed that among the dyes, members 3a and 3b possessed localized and non-continuous electron distribution in their frontier orbitals as well as maximum amount of oscillator strength.
设计并合成了一系列基于5-氨基间苯二甲酸、具有不同共轭长度和不同供体部分的新型偶氮染料。利用偶氮苯单元作为π-间隔部分来扩展共轭范围并连接供体和受体单元。当二烷基氨基取代基从二甲基变为二乙醇时，观察到吸收光谱和λ发生红移。对直接合成的染料在溶液中和光阳极表面的光物理和电化学性质进行了研究，这表明这些染料适合用作染料敏化太阳能电池（DSSC）的光敏剂。由于带有两个锚定电子接受基团，预计染料在TiO表面的吸附强度以及光捕获能力会增加，这可能导致电子转移（ET）增强。ATR吸收光谱清楚地表明这些染料吸附在TiO表面。人们认识到，增加π-共轭长度以及含羟基的供体基团会提高DSSC的光伏性能。带隙减小以及电子复合受到抑制和染料再生得到改善被认为在提高性能参数方面起着重要作用。与先前合成的其他间位偶氮染料的效率相比，基于这些染料的DSSC表现出更高的太阳能转换效率。理论计算（DFT/TDDFT）表明，在这些染料中，成员3a和3b在其前沿轨道中具有局域化和非连续的电子分布以及最大量的振子强度。
