Arrays of CdSe sensitized ZnO/ZnSe nanocables for efficient solar cells with high open-circuit voltage
Arrays of CdSe sensitized ZnO/ZnSe nanocables for efficient solar cells with high open-circuit voltage
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DOI：
10.1039/c2jm31970e
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发表时间：
2012-06
影响因子：
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通讯作者：
Jun Xu;Xia Yang;Qingdan Yang;T. Wong;Shui-Tong Lee;Wenjun Zhang;Chun‐Sing Lee
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文献类型：
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作者：
Jun Xu;Xia Yang;Qingdan Yang;T. Wong;Shui-Tong Lee;Wenjun Zhang;Chun‐Sing Lee
以ZnO纳米线为前驱体，通过原位连续离子交换，在FTO （SnO2: F）玻璃衬底上合成了高度有序的CdSe包覆ZnO/ZnSe核壳纳米电缆阵列，无需任何有机配体。而开路电压较低(VOC)(通常低于0.72 V)是一个主要因素限制的功率转换效率(PCE)量子点敏化太阳能电池(QDSSCs),我们设计和开发的氧化锌阵列/奈米/ CdSe nanocables高效光电极的光电化学太阳能电池(压电陶瓷),达到4.54%的PCE和VOC高达0.836 V通过使用纳米忍耐力对电极下是1.5克照明强度的100 mW厘米−2。高光电电压归因于具有高导带边缘的ZnSe层，它通过钝化ZnO纳米线表面来减少载流子复合，并向上移动ZnO在异质结中的导带。使用典型的铂化FTO （Pt/FTO）反电极，可实现高达0.855 V的VOC。然而，Cu2S反电极具有更高的催化活性，有助于提高填充因子（FF）和短路电流密度（JSC），从而使PCE提高55%。
Highly ordered arrays of CdSe coated ZnO/ZnSe core–shell nanocables on FTO (SnO2 : F) glass substrates have been synthesized using ZnO nanowires as precursors via in situ successive ion exchanges without any organic ligands involved. While the low open-circuit voltage (VOC) (typically below 0.72 V) is a main factor limiting the power conversion efficiency (PCE) of quantum dot sensitized solar cells (QDSSCs), we design and exploit the arrays of ZnO/ZnSe/CdSe nanocables as efficient photoelectrodes for photoelectrochemical (PEC) solar cells, achieving a PCE of 4.54% and a VOC as high as 0.836 V by using a nanostructured Cu2S counter-electrode under AM 1.5G illumination with an intensity of 100 mW cm−2. The high photovoltage is attributed to the ZnSe layer with a high conduction band edge, which reduces carrier recombination by passivizing the surface of ZnO nanowires and upwardly shifts the conduction band of ZnO in the heterojunction. A VOC up to 0.855 V is achieved for the same cell using a typical platinized FTO (Pt/FTO) counter-electrode. However, the Cu2S counter-electrode, which is demonstrated to have higher catalytic activity, contributes to improvements in the fill factor (FF) and short-circuit current density (JSC) and consequently results in a 55% improvement in PCE.