Porphyrin sensitizers containing an auxiliary benzotriazole acceptor for dye-sensitized solar cells: Effects of steric hindrance and cosensitization was written by Song, Heli;Tang, Weiqiang;Zhao, Shuangliang;Liu, Qingyun;Xie, Yongshu. And the article was included in Dyes and Pigments in 2018.SDS of cas: 100189-84-2 This article mentions the following:
Dye-sensitized solar cells (DSSCs) have attracted intensive attention in developing photovoltaic devices for employing solar energy. For developing panchromatic and efficient porphyrin sensitizers, it has been demonstrated to be an effective approach to introduce an electron-withdrawing benzothiadiazole unit as an extra electron acceptor. In contrast, the structurally similar benzotriazole moiety remains relatively unknown in this respect. In this work, we have synthesized a novel porphyrin dye containing an extra electron acceptor of benzotriazole. Photophys. and electrochem. investigations revealed red-shifted absorption and a narrower band gap induced by the benzotriazole unit. Thus, a reasonable efficiency of 8.39% has been achieved with a Jsc of 17.00mAcm-2 and a Voc of 712mV. On this basis, to investigate the effect of the dihedral angle between the benzotriazole and the adjacent phenylene ring, one or two Me groups were attached to the ortho-positions of the phenylene ring. As a result, the enlarged torsion angles induce poor electronic coupling between the LUMO of the dyes and TiO2, resulting in lower efficiencies of 6.61% and 3.62%, resp. With the purpose to further improve the efficiencies, coadsorption and cosensitization approaches were employed. And the efficiencies have been successfully elevated to 9.32%, 8.49% and 7.34%, resp. These results demonstrate the effectiveness of incorporating an auxiliary benzotriazole acceptor into porphyrin dyes on achieving extended light-harvesting wavelength ranges and illustrate the importance of avoiding severe torsion within the acceptor part of the porphyrin dyes. In contrast to the commonly used cosensitizers with absorption peaks lying in the absorption valley between the Soret band and the Q bands of porphyrin dyes (500-600nm), the utilization of an organic dye with broad absorption in this work has been demonstrated to be effective for improving the efficiencies despite the fact that its absorption peak at 450nm largely overlaps with the Soret band of the porphyrin dyes. These results provide an alternative approach for developing cosensitizers for porphyrin dyes. In the experiment, the researchers used many compounds, for example, 2,5-Dibromo-1,3-dimethylbenzene (cas: 100189-84-2SDS of cas: 100189-84-2).
2,5-Dibromo-1,3-dimethylbenzene (cas: 100189-84-2) belongs to organobromine compounds. Most of the natural organobromine compounds are produced by marine organisms, and several brominated metabolites with antibacterial, antitumor, antiviral, and antifungal activity have been isolated from seaweed, sponges, corals, molluscs, and others. In the pharmaceutical industry organo bromine derivatives are used as sedatives, vasodilators, antiseptic agents, and anticancer agents.SDS of cas: 100189-84-2
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary