Zhang Zhipan, Zakeeruddin Shaik M, O'Regan Brian C, Humphry-Baker Robin, Grätzel Michael
Laboratory for Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland.
J Phys Chem B. 2005 Nov 24;109(46):21818-24. doi: 10.1021/jp054305h.
Dye-sensitized solar cells based on nanocrystalline TiO(2) have been fabricated with an amphiphilic ruthenium sensitizer [Ru (4,4'-dicarboxylic acid-2,2'-bipyridine) (4,4'-bis(p-hexyloxystyryl)-2,2'-bipyridine)(NCS)(2)], coded as K-19, and 4-guanidinobutyric acid (GBA) as coadsorbent. The cells showed a approximately 50 mV increase in open-circuit voltage and a similar current in comparison with cells without GBA cografting. The performance of both types of devices was evaluated on the basis of their photocurrent-voltage characteristics, dark current measurements, cyclic voltammetry, electrochemical impedance spectroscopy, and phototransient decay methods. The results indicate that GBA shifted the conduction band of TiO(2) toward a more negative potential and reduced the interfacial charge-transfer reaction from conduction band electrons to triiodide in the electrolyte (also known as the back reaction). In addition, the devices with GBA cografting showed an excellent stability with a power conversion efficiency of approximately 8% under simulated full sunlight (air mass 1.5, 100 mW cm(-2)) during visible light soaking at 60 degrees C.
基于纳米晶TiO₂的染料敏化太阳能电池已采用两亲性钌敏化剂[Ru (4,4'-二羧酸-2,2'-联吡啶)(4,4'-双(对己氧基苯乙烯基)-2,2'-联吡啶)(NCS)₂]（编码为K-19）和4-胍基丁酸（GBA）作为共吸附剂制备而成。与未共接枝GBA的电池相比，这些电池的开路电压提高了约50 mV，电流相似。基于光电流-电压特性、暗电流测量、循环伏安法、电化学阻抗谱和光瞬态衰减方法对这两种器件的性能进行了评估。结果表明，GBA使TiO₂的导带向更负的电位移动，并减少了电解质中从导带电子到三碘化物的界面电荷转移反应（也称为背反应）。此外，共接枝GBA的器件表现出优异的稳定性，在60℃可见光浸泡期间，在模拟全阳光（空气质量1.5，100 mW cm⁻²）下功率转换效率约为8%。
