ZnO nanostructures as efficient antireflection layers in solar cells
ZnO nanostructures as efficient antireflection layers in solar cells
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DOI：
10.1021/nl080659j
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发表时间：
2008-05-01
期刊：
影响因子：
10.8
通讯作者：
Hsu, Julia W. P.
中科院分区：
文献类型：
--
作者：
Lee, Yun-Ju;Ruby, Douglas S.;Hsu, Julia W. P.
有效的抗反射涂层（ARC）可以通过增加光耦合来增强太阳能电池性能。在这里，我们研究溶液生长的ZnO纳米结构作为ARC的硅太阳能电池，并将其与传统的单层ARC进行比较。我们发现，纳米形态，通过合成化学控制，宏观ARC性能有很大的影响。与氮化硅（SiN）单层ARC相比，ZnO纳米棒阵列显示出从400到1200 nm的宽带反射抑制。对于平均尖端直径为10 nm的锥形纳米棒阵列，我们实现了6.6%的加权全局反射率，这上级优化的SiN单层ARC。使用严格的耦合波分析的计算表明，锥形纳米棒阵列表现得像改性的单层ARC，其中锥形导致Si和空气之间的阻抗匹配，通过逐渐降低远离表面的有效折射率，导致低反射，特别是在较长的波长，并通过粗糙化的空气-ZnO界面消除干涉条纹。根据计算，我们可以通过调整底部熔融ZnO层的厚度和通过更好地控制尖端锥形来进一步改善ARC性能。
An efficient antireflection coating (ARC) can enhance solar cell performance through increased light coupling. Here, we investigate solution-grown ZnO nanostructures as ARCs for Si solar cells and compare them to conventional single layer ARCs. We find that nanoscale morphology, controlled through synthetic chemistry, has a great effect on the macroscopic ARC performance. Compared with a silicon nitride (SiN) single layer ARC, ZnO nanorod arrays display a broadband reflection suppression from 400 to 1200 nm. For a tapered nanorod array with average tip diameter of 10 nm, we achieve a weighted global reflectance of 6.6%, which is superior to an optimized SiN single layer ARC. Calculations using rigorous coupled wave analysis suggest that the tapered nanorod arrays behave like modified single layer ARCs, where the tapering leads to impedance matching between Si and air through a gradual reduction of the effective refractive index away from the surface, resulting in low reflection particularly at longer wavelengths and eliminating interference fringes through roughening of the air-ZnO interface. According to the calculations, we may further improve ARC performance by tailoring the thickness of the bottom fused ZnO layer and through better control of tip tapering.