Systematic stacking of PbS/CdS/CdSe multi-layered quantum dots for the enhancement of solar cell efficiency by harvesting wide solar spectrum
Systematic stacking of PbS/CdS/CdSe multi-layered quantum dots for the enhancement of solar cell efficiency by harvesting wide solar spectrum
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DOI：
10.1016/j.electacta.2018.03.193
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发表时间：
2018-05
影响因子：
6.6
通讯作者：
A. Manjceevan;J. Bandara
中科院分区：
文献类型：
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作者：
A. Manjceevan;J. Bandara
多层量子点敏化太阳能电池，特别是含有两层以上q点作为光收集材料的q点太阳能电池，由于外层q点对内部优化q点层的不利影响，是一个很大的挑战。在这项工作中，将PbS（带隙1.16 eV）、CdS（带隙2.01 eV）和CdSe（带隙1.76 eV）的多个带隙q点以不同的组合方式堆叠在介孔tio2层上，以增强光捕获能力。研究了在介孔tio2层上多层q点的叠加问题。将不同堆叠结构的多带q点太阳能电池的光电性能与多带隙量子点的光电性能进行了比较。优化后的三层PbS/CdS/CdSe制备的q点太阳能电池效率为6.2%，而PbS/CdS和CdS/CdSe制备的两层q点太阳能电池效率分别为5.8%和4.2%。发现三层PbS/CdS/CdSe q点太阳能电池性能的增强主要是由于三个q点层在光阳极上适当的级联堆叠，从而增强了电荷输运和光收获。
Fabrication of multi-layered quantum dot sensitized solar cells, especially q-dot solar cells that contain more than two layers of q-dots as light harvesting materials is a great challenge due to adverse effects exert by the q-dots in the outer-layers on the inner optimized q-dot layer. In this work, multi-bandgap q-dots of PbS (bandgap 1.16 eV), CdS (bandgap 2.01 eV) and CdSe (bandgap1.76 eV) are stacked in different combinations on the mesoporous TiO2layer to enhance the light harvesting ability. The problems associated with stacking of multi-layers of q-dots on the mesoporous TiO2layer were also investigated. The observed photovoltaic properties of multiband q-dot solar cells with different stacking configurations are then compared with the optical and electrical properties of multi-band gap quantum dots. The optimized three-layer PbS/CdS/CdSe q-dot solar cell showed a solar cell efficiency of 6.2% while two-layer q-dot solar cells fabricated with PbS/CdS and CdS/CdSe showed solar cell efficiencies of 5.8 and 4.2% respectively. The enhanced solar cell performance of three-layer PbS/CdS/CdSe q-dot solar cell is found to be mainly due to proper cascade stacking of three q-dot layers in photoanode that ensuing in enhanced charge transport as well as higher light harvesting.