We present an investigation of the effects of a change in the protonation state of the phosphonic acid anchoring ligand in the dye [Cu(H₄1)(2)][PF₆] (H₄1 = ((6,6′-dimethyl-[2,2′-bipyridine]-4,4′-diyl)bis(4,1-phenylene))bis(phosphonic acid), 2 = 4,4′-bis(4-bromophenyl)-6,6′-dimethyl-2,2′-bipyridine) on the performance of n-type dye-sensitized solar cells (DSCs). FTO/TiO₂ electrodes were immersed in solutions of H₄1 in the presence of base (0–4 equivalents). TiO₂-anchored heteroleptic copper(I) sensitizers were subsequently formed by ligand exchange between the homoleptic complex [Cu(2)₂][PF₆] and the anchored ligand [H_4−n1]ⁿ⁻. The results demonstrate that the addition of one equivalent of base during the initial surface functionalization can afford up to a 26% increase in DSC efficiency, while the addition of ≥3 equivalents of base significantly hinders DSC performance. Deprotonation of H₄1 has been investigated using ¹H and ³¹P NMR spectroscopic titrations. Further insight into DSC performance has been gained by using electrochemical impedance spectroscopy, and a comparison is made between DSCs in which the working electrodes are either pre-treated with a base, or exposed to a base post heteroleptic copper(I) dye-assembly.

中文翻译：

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膦酸质子化状态对双（二亚胺）铜（i）染料敏化太阳能电池效率的影响†

我们目前对染料[Cu（H ₄ 1）（2）] [PF ₆ ]（H ₄ 1 =（（6,6'-二甲基-[2,2'-联吡啶] -4,4'-二基）双（4,1-亚苯基））双（膦酸），2 = 4,4'-双（4-溴苯基）-6,6 ′-二甲基-2,2′-联吡啶）对n型染料敏化太阳能电池（DSCs）性能的影响。将FTO / TiO ₂电极浸入H ₄ 1在碱（0–4当量）存在的溶液中。的TiO ₂锚定杂铜（我）敏化剂随后通过均配型络合物[Cu（上之间的配体交换形成2）₂ ] [PF ₆ ]和锚定的配体[H _{4- Ñ} 1 ] ^{ñ -} 。结果表明，在初始表面功能化过程中添加一当量的碱可以使DSC效率提高多达26％，而≥3当量的碱的添加则显着阻碍DSC性能。使用¹ H和³¹研究了H ₄ 1的去质子化1 H NMR光谱滴定。通过使用电化学阻抗谱对DSC的性能有了进一步的了解，并且在DSC之间进行了比较，在DSC中，工作电极要么经过碱预处理，要么暴露于杂铜（I）染料组装后暴露于碱中。