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. Photophysical and electrochemical 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 J_sc of 17.00 mA cm⁻² and a V_oc of 712 mV. On this basis, to investigate the effect of the dihedral angle between the benzotriazole and the adjacent phenylene ring, one or two methyl 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%, respectively. 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%, respectively. 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 (500–600 nm), 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 450 nm largely overlaps with the Soret band of the porphyrin dyes. These results provide an alternative approach for developing cosensitizers for porphyrin dyes.

染料敏化太阳能电池（DSSC）在开发用于利用太阳能的光伏设备中引起了广泛的关注。对于开发全色和有效的卟啉敏化剂，已证明是引入吸电子苯并噻二唑单元作为额外电子受体的有效方法。相反，在这方面，结构相似的苯并三唑部分仍然相对未知。在这项工作中，我们合成了一种新型的卟啉染料，其中含有一个额外的苯并三唑电子受体。光物理和电化学研究表明，苯并三唑单元会引起红移吸收和较窄的带隙。因此，J _sc为17.00 mA cm ^-2时，已达到8.39％的合理效率。和V _OC 712毫伏。在此基础上，为了研究苯并三唑与相邻的亚苯基环之间的二面角的影响，将一个或两个甲基连接至亚苯基环的邻位。结果，增大的扭转角在染料的LUMO和TiO ₂之间引起不良的电子耦合。，导致效率分别降低了6.61％和3.62％。为了进一步提高效率，采用了共吸附和共敏化方法。效率已分别成功提升至9.32％，8.49％和7.34％。这些结果证明了将辅助的苯并三唑受体结合到卟啉染料中对于实现扩展的光收集波长范围的有效性，并且说明了避免卟啉染料的受体部分内的严重扭转的重要性。与通常使用的增敏剂的吸收峰位于卟啉染料的Soret带和Q带之间（500-600 nm）之间的吸收峰相反，尽管在450nm处的吸收峰与卟啉染料的Soret带大大重叠，但事实证明，在这项工作中利用具有广泛吸收率的有机染料可有效提高效率。这些结果为开发用于卟啉染料的增敏剂提供了另一种方法。