化学学报 ›› 2014, Vol. 72 ›› Issue (5): 624-629.DOI: 10.6023/A13121232 上一篇    

研究论文

不同结构的氧化钛纳米金复合薄膜的光伏特性

苑琪, 陈雪景, 王京涛, 翟锦   

  1. 北京航空航天大学化学与环境学院 仿生智能科学与技术教育部重点实验室 北京 100191
  • 投稿日期:2013-12-10 发布日期:2014-03-20
  • 通讯作者: 翟锦 E-mail:zhaijin@buaa.edu.cn
  • 基金资助:

    项目受国家自然科学基金(No. 21073009)、国家教育部博士点基金(No. 30400002011127001)和国家重点基础研究发展计划(973)(No. 2011CB935704,2012CB720904)资助.

Photovoltaic Performance of Plasmonic Thin Films with Different Structure of Au and TiO2

Yuan Qi, Chen Xuejing, Wang Jingtao, Zhai Jin   

  1. School of Chemistry and Environment, Beihang University, Xueyuan Road, Haidian District, Beijing 100191
  • Received:2013-12-10 Published:2014-03-20
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21073009), Ph. D. Programs Foundation of Ministry of Education of China (No. 30400002011127001) and National Basic Research Program (Nos. 2011CB935704, 2012CB720904).

具有表面等离子体共振效应的金属和氧化物复合纳米结构被应用在染料敏化太阳能电池(DSSC)中以提高电池的光电转换效率,金属纳米粒子和氧化物薄膜的复合结构对于等离子体共振器件在电池上的效果有巨大的影响. 我们研究了不同氧化钛薄膜和纳米金复合体系(纳米金分别修饰在氧化钛薄膜的表面和下表面)的光电转换效果,其中当纳米金修饰在氧化钛薄膜表面时薄膜的紫外可见吸收增加最大. 然而,经过染料敏化之后,该体系的光电转换效率比未修饰的薄膜有所降低,而纳米金修饰在氧化钛薄膜下表面时,光电转换效率比未修饰时提高了37%,同时入射单色光子-电子转化效率(IPCE)也有相应提高. 为了进一步研究纳米金在复合薄膜中的作用,我们引入了TiO2-Au-TiO2的三明治体系,该体系的光电转换效率比未修饰的参比氧化钛薄膜仍有所提高. 上述研究结果表明等离子体共振器件的结构设计对于染料敏化太阳能电池的改善具有重要意义. 同时,我们对于纳米金的等离子体共振效应做了离散偶极子近似(Dipole Discrete Approximation)模拟计算,其结果支持了实验数据. 该研究对于未来太阳能电池中表面等离子体共振器件的设计具有一定指导意义.

关键词: 等离子体薄膜, 纳米金, 染料敏化太阳能电池, 光电转换效率

Metal-oxide nanostructures with Surface Plasmon Resonance (SPR) have been introduced to improve the light absorption ability of dye sensitized solar cells (DSSCs) so that the energy conversion efficiency can be enhanced. It should be noted that the structure of metal nanoparticles and the oxide substrate greatly influence the performance of the solar cells, both to utilize SPR to the fullest and to overcome the drawbacks such as charge recombination involved with metal nanoparticles. We studied the morphology of spin-coated thin films with different structures of Au and TiO2, FTO/TiO2/Au NPs, FTO/Au NPs/TiO2 and FTO/TiO2/Au/TiO2 and examined the surface plasmon resonance effect on the light absorption ability and energy conversion behavior of dye sensitized solar cells with the as fabricated thin films as photo anodes. Electrode with Au NPs loaded on the top of TiO2 thin film showed improved optical absorption in the visible region compared to the control sample of TiO2 due to the surface plasmon resonance of Au NPs. However, the dye sensitized TiO2-Au NPs films showed decreased photocurrent under illumination due to the charge recombination caused by bare Au NPs. On the other hand, when Au NPS were loaded beneath the TiO2 film, the plasmonic electrode exhibited a 37% enhancement and increased incident photon-to-photocurrent efficiency (IPCE) in consistent with the improvement in absorption spectrum. To further confirm the role of Au NPs in the plasmonic films, the sandwich-like structure of TiO2-Au-TiO2 was introduced, behaving improved photovoltaic performance compared to the control TiO2 electrode. Such results reveal that the design of structure can be of great importance to identify the favorably enhanced direction of plasmonic structure resulting from plasmonic scattering to trap light which confines light within the active TiO2 layer to promote DSSCs. Dipole Discrete Approximation (DDA) simulation feedback supported the experimental results. This concept is applicable to potential plasmonic devices for DSSCs.

Key words: plasmonic thin film, metal nanostructure, DSSC, photovoltaic performance