Enhancement of the performance of dye-sensitized solar cell by formation of shallow transport levels under visible light illumination
Enhancement of the performance of dye-sensitized solar cell by formation of shallow transport levels under visible light illumination
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DOI：
10.1021/jp800426y
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发表时间：
2008-04
影响因子：
3.7
通讯作者：
Qing Wang;Zhipan Zhang;S. Zakeeruddin;M. Graetzel
中科院分区：
文献类型：
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作者：
Qing Wang;Zhipan Zhang;S. Zakeeruddin;M. Graetzel
通过阻抗谱和光电压瞬态衰减测量研究了可见光浸泡下无锂和含锂电解质中染料敏化太阳能电池（DSC）的性能增强。发现这种改善是由于形成了接近导带的电子传输能级，这很可能是由于光诱导质子嵌入TiO2纳米颗粒所致。这些浅陷阱态加速了纳米晶薄膜内的电荷载流子输运，而不会劣化开路光电压。使电池在黑暗中经受正向偏压产生类似的效果，而在电解质中引入锂离子抑制了由于普遍的锂离子嵌入而引起的现象。局域态在二氧化钛的带隙和由此产生的导带边缘移动的重新分配似乎发挥了显着的作用，在DSC的性能。
The performance enhancement of dye-sensitized solar cells (DSCs) in lithium-free and lithium-containing electrolytes under visible light-soaking was examined by impedance spectroscopy and photovoltage transient decay measurements. The improvement was found to arise from the formation of electronic transport levels close to the conduction band, resulting most likely from photoinduced proton intercalation in the TiO2 nanoparticles. These shallow trapping states accelerate the charge carrier transport within the nanocrystalline films without deteriorating the open circuit photovoltage. Subjecting the cells to forward bias in the dark produces a similar effect, whereas the introduction of lithium ions in the electrolyte suppresses the phenomena due to prevailing lithium ion intercalation. The redistribution of localized states in the band gap of TiO2 and the resulting conduction band edge movement appears to play a significant role in the performance of the DSC.