标题: 钌金属染料奈米管染料敏化太阳能电池之制作与鉴识
Fabrication and Characterization of Titanium Oxide Nanotube-based Dye Sensitized Solar Cells
作者: 吴柏霆
Wu, Po-Ting
刁维光
Diau, Wei-Guang
应用化学系硕博士班
关键字: 染料敏化太阳能电池;钌金属错合物;DSSC;Ruthenium Complex
公开日期: 2012
摘要: 二氧化钛奈米管薄膜由于具有一维传导特性,使得一维方向的电子传导速率较快、电子电洞分离率也较高,电子-电洞再结合率也因此下降,因此,相当适合应用于染料敏化太阳能电池(Dye-sensitized solar cell)之光阳极,并可应用于气体感应器、光催化,锂电池等其他领域。本论文即是以阳极处理方法制备一维二氧化钛奈米管(TiO2 nanotube, TNT)光阳极结构结合本实验室开发之新颖钌金属染料RD16-RD18,制备高效能之TNT-DSSC元件,并量测其光电转换效率、入射光子-光电流转换效率、瞬态衰减光谱来探讨染料分子结构对于染料敏化太阳能电池(DSSC)元件之电子传递及电荷重组过程所造成的影响。
由所制备之奈米管元件,RD16导入苯并咪唑以及带有阴电性的氟,并在联吡啶上加入噻吩官能基团,有效提升了元件的短路电流,让电池元件的效率达到7.18%。修饰RD16结构中接上长碳链基团的RD17与具有双噻吩及长碳链基团的RD18染料,则因有明显的团聚现象而造成染料吸附量的低下与电流下降,尤其以RD18团聚现象最为严重。配合瞬态衰减光谱与电荷萃取技术的分析,得知二氧化钛在RD系统中导带位置为:RD16 < RD17 < RD18;电子生命期(□R)之趋势为:RD17 □ RD16 > RD18。将RD系列染料搭配上DINHOP以及CDCA共吸附剂,经过元件效率最佳化,在35μm的奈米管元件中,RD16染料搭配上适当比例之CDCA共吸附剂,可得到14.983 mAcm-2的光电流,VOC = 0.714V,FF = 67.05,效率也高达7.18%。
Self-organized 1-D titania nanotube (TNT) arrays have a great potential as materials for photocatalysis, self-cleaning, gas sensing, lithium batteries and dye-sensitized solar cells (DSSC) due to their excellent charge collection efficiency and slow charge recombination. In this work we fabricated highly efficient TiO2 nanotubes-based dye-sensitized solar cells sensitized by novel heteroleptic ruthenium dyes, RD16-RD18, and studied electron transport and charge recombination kinetics of the relative devices using transient photocurrent/photovoltage decay and charge extraction techniques.
A series of heteroleptic ruthenium complexes RD16-RD18 containing fluoro- substituted and thiophene-based benzimidazole ligands were developed by Professor Diau’s group. The RD16-sensitized TNT-DSSC reveals an enhanced short-circuit current density (JSC) and efficiency (□) of power conversion compared to N719 due to the increasing light-harvesting and the broadened spectral features with thiophene-based ligands. However, the devices made of RD17 and RD18 were confronted by the poor adsorption of dyes on TNT surface resulting in a decreased short-circuit current density especially in RD18. Instead of retarding charge recombination, the substitution of thiophene and long alkyl chain in RD17 and RD18 caused an aggregation of sensitizers. Investigating using the photovoltage decay and charge extraction measurements, we found that the TiO2 potential shift downward in a systematic trend of Ecb : RD16 < RD17 < RD18 and the electron lifetimes show the order of RD17 □ RD16 > RD18. In order to preventing the aggregation, co-absorber, DINHOP and CDCA, were introduced in RD sensitizers. Upon optimization, the device made of RD16 yielded JSC/mA cm-2 = 14.98, VOC/mV = 714, FF = 0.67 and the efficiency reaches 7.18 %.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT079925555
http://hdl.handle.net/11536/49889
显示于类别:Thesis