Significant enhancement of optical absorption through nano-structuring of copper based oxide semiconductors: possible future materials for solar energy applications
Significant enhancement of optical absorption through nano-structuring of copper based oxide semiconductors: possible future materials for solar energy applications
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DOI：
10.1039/c4cp00827h
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发表时间：
2014-01-01
影响因子：
3.3
通讯作者：
Ghosh, Kartik
中科院分区：
文献类型：
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作者：
Bhaumik, Anagh;Shearin, Austin M.;Ghosh, Kartik
光吸收系数是决定太阳能电池工作效率的一个重要参数。众所周知，无机纳米晶体是太阳能电池纳米技术的基准模型，因为其光学性质的可调性和特定相的稳定性在纳米尺度上是唯一可能的。采用水热法制备纳米氧化铜，通过改变基质、反应温度、反应时间等生长参数，制备出纳米氧化铜的形状、尺寸和相。利用x射线衍射（XRD）、扫描电子显微镜（SEM）、拉曼光谱（Raman spectroscopy）、光致发光（PL）和紫外可见光谱（UV-vis spectroscopy）研究了纳米晶体的结构、相、形貌、分子振动模式和光学性质。在纳米结构铜氧化物的特定相混合物中，观察到明显的大光学吸收系数，在可见光范围内是Si的两倍。在525 nm处，铜氧化物的光学吸收系数为7.05 10(+5)cm(-1)，明显大于商业纯CuO (1.19 10（+5) cm(-1)）和Si (1.72 10（+5) cm(-1)）。本文还讨论了相混合物的可能形成机制和氧化铜的形态，为高效太阳能电池中类似形态纳米结构的合成开辟了道路。
The optical absorption coefficient is a crucial parameter in determining solar cell efficiency under operational conditions. It is well known that inorganic nanocrystals are a benchmark model for solar cell nanotechnology, given that the tunability of optical properties and stabilization of specific phases are uniquely possible at the nanoscale. A hydrothermal method was employed to fabricate nanostructured copper oxides where the shape, size and phase were tailored by altering the growth parameters, namely the base media used, the reaction temperature, and the reaction time. The nano crystalline structures, phases, morphology, molecular vibrational modes, and optical properties were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence (PL), and UV-vis spectroscopy. A significantly large optical absorption coefficient, of the order of twice that of Si in the visible range, was observed in a particular phase mixture of nanostructured copper oxides. An optical absorption coefficient of 7.05 10(+5) cm(-1) at 525 nm was observed in a particular nanostructured phase mixture of copper oxides which is appreciably larger than commercially pure CuO (1.19 10(+5) cm(-1)) and Si (1.72 10(+5) cm(-1)). A possible mechanism of formation of phase mixtures and morphology of copper oxides has also been discussed, which opens up a roadmap in synthesis of similar morphology nanostructures for efficient solar cells.