Four newly designed unsymmetrical squaraine dyes bearing different functional groups for their anchoring on the surface of mesoporous TiO₂ were successfully synthesized aiming towards development of far-red sensitizers for dye-sensitized solar cells (DSSCs). The synthesized dyes were characterized by ¹H NMR, fast ion bombardment mass, and subjected to photophysical investigations by electronic absorption/fluorescence emission spectroscopy and cyclic voltammetry. These dyes exhibited excellent solubility in a number of common organic solvents. Adsorption behavior of these dyes on the thin films of mesoporous TiO₂ was investigated in detail and results indicated that rate of dye adsorption follows the order −COOH>-PO₃H₂>OH > SO₃H. At the same time, dye desorption studies demonstrated that stability of adsorbed dyes on the mesoporous TiO₂ follows the order -PO₃H₂>>OH>−COOH > –SO₃H. Further, implication of the nature of anchoring groups of dye molecules upon the energy levels of their highest occupied molecular orbital and lowest unoccupied molecular orbital was evaluated by both of the combined theoretical and experimental approaches. In spite of enhanced dye loading, very high binding strength and favorable energetic cascade, SQ-143 bearing Phosphonic acid exhibited hampered photovoltaic performance as compared to that of SQ-138 with carboxylic acid anchoring group. Amongst various sensitizers used for present investigation, SQ-138 exhibited best photovoltaic performance having short-circuit current density, open circuit voltage and fill factor of 12.49 mA/cm², 0.60 V, and 0.53, respectively, leading to power conversion efficiency of 4.07 % after simulated solar irradiation.

为了开发用于染料敏化太阳能电池（DSSC）的远红敏化剂，成功合成了四种新设计的不对称方酸菁染料，它们具有不同的官能团固定在介孔TiO ₂的表面上。合成的染料通过¹ H NMR，快速离子轰击质量进行表征，并通过电子吸收/荧光发射光谱法和循环伏安法进行光物理研究。这些染料在多种常见有机溶剂中显示出极好的溶解性。详细研究了这些染料在介孔TiO ₂薄膜上的吸附行为，结果表明染料的吸附速率遵循-COOH> -PO ₃ H ₂的顺序。> OH> SO ₃ H.与此同时，解吸染料的研究表明，吸附染料的对中孔二氧化钛稳定性₂如下顺序-PO ₃ ħ ₂ >> OH> -COOH> -SO ₃H.此外，通过结合的理论和实验方法，都评估了染料分子锚定基团的性质对其最高占据分子轨道和最低未占据分子轨道的能级的影响。尽管增加了染料负载量，非常高的结合强度和良好的能量级联，但与带有羧酸锚定基团的SQ-138相比，带有膦酸的SQ-143仍显示出受阻的光伏性能。之中用于本研究的各种敏化剂，SQ-138显示出具有短路电流密度，开路电压和填充因子12.49毫安/厘米的最好光伏性能²分别，0.60 V，和0.53，，导致4.07的功率转换效率模拟太阳辐射后的百分比。