Tunç Gülenay, Zambrano-Angulo Michael, Arslan Barış Seçkin, Güzel Emre, Nebioğlu Mehmet, Ahsen Vefa, Şişman İlkay, Cárdenas-Jirón Gloria, Gürek Ayşe Gül
Department of Chemistry, Gebze Technical University, Kocaeli, Turkey.
Laboratory of Theoretical Chemistry, Faculty of Chemistry and Biology, University of Santiago de Chile (USACH), Santiago, Chile.
Dalton Trans. 2021 Mar 2;50(8):2981-2996. doi: 10.1039/d0dt03696j.
Push-pull zinc phthalocyanine dyes bearing hexylsulfanyl moieties as electron donors and carboxyethynyl as mono- or di-anchoring groups have been designed, synthesized and tested as sensitizers in dye-sensitized solar cells (DSSCs). The effects of the anchoring groups on the optical, electrochemical and photovoltaic properties were investigated. The incorporation of a carboxyethynyl group in GT23 has a considerable effect on preventing dye aggregation due to its relatively non-planar structure. The mono-anchoring dye bearing a phenyl carboxyethynyl group, GT5, has a higher molar extinction coefficient and sufficient charge injection into the TiO2 conduction band. Therefore, GT5 achieved at least 90% higher power conversion efficiency than the di-anchoring dyes (GT31 and GT32). Time-dependent density functional theory (PBE0/6-31G(d,p)) was also used to calculate the electronic absorption spectra, which predicted very well the measured UV-Vis with an error of up to 0.11 eV for the Q bands and 0.3 eV for the B bands. The longest charge transfer bands are obtained in the visible light region and they correspond to a transfer phthalocyanine core → substituent with a carboxyethynyl group where the absorptions of GT32 (465 nm) and GT31 (461 nm) are red-shifted compared to GT23 (429 nm) and GT5 (441 nm). The interaction energy between the phthalocyanine and a cluster of anatase-TiO2 (H4Ti40O82) was calculated using density functional theory. For all phthalocyanines, the interaction favored is monodentate and corresponds to -O(OH)Ti(TiO2), where the stronger interaction occurs for GT32 (-2.11 eV) and GT31 (-2.25 eV). This study presents the molecular combination of the anchoring groups in zinc phthalocyanine sensitizers, which is one of the effective strategies for improving the performance of DSSCs.
设计、合成并测试了以己基硫烷基团作为电子供体且以羧基乙炔基作为单锚定或双锚定基团的推拉型锌酞菁染料，将其作为染料敏化太阳能电池（DSSC）中的敏化剂。研究了锚定基团对光学、电化学和光伏性能的影响。GT23中羧基乙炔基的引入因其相对非平面的结构，对防止染料聚集有相当大的影响。带有苯基羧基乙炔基的单锚定染料GT5具有更高的摩尔消光系数，并且能向TiO₂导带充分注入电荷。因此，GT5的功率转换效率比双锚定染料（GT31和GT32）至少高90%。还使用含时密度泛函理论（PBE0/6 - 31G(d,p)）来计算电子吸收光谱，该理论对测得的紫外 - 可见光谱预测得很好，Q带误差高达0.11 eV，B带误差为0.3 eV。最长的电荷转移带出现在可见光区域，它们对应于酞菁核心→带有羧基乙炔基取代基的转移，其中GT32（465 nm）和GT31（461 nm）的吸收相对于GT23（429 nm）和GT5（441 nm）发生了红移。使用密度泛函理论计算了酞菁与锐钛矿 - TiO₂簇（H4Ti40O82）之间的相互作用能。对于所有酞菁，有利的相互作用是单齿的，对应于 -O(OH)Ti(TiO2)，其中GT32（-2.11 eV）和GT31（-2.25 eV）的相互作用更强。本研究展示了锌酞菁敏化剂中锚定基团的分子组合，这是提高DSSC性能的有效策略之一。
