2D layered insulator hexagonal boron nitride enabled surface passivation in dye sensitized solar cells.
2D layered insulator hexagonal boron nitride enabled surface passivation in dye sensitized solar cells.
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DOI：
10.1039/c3nr03767c
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发表时间：
2013-10
期刊：
影响因子：
6.7
通讯作者：
M. Shanmugam;R. Jacobs-Gedrim;C. Durcan;Bin Yu
中科院分区：
文献类型：
--
作者：
M. Shanmugam;R. Jacobs-Gedrim;C. Durcan;Bin Yu
提出了一种用于染料敏化太阳能电池的新型表面钝化材料--六方氮化硼(h-BN)，以减少界面载流子复合。我们观察到，与没有表面钝化的器件相比，使用h-BN涂层的半导体TiO2光转换效率提高了约57%。用拉曼光谱对h-BN包覆的二氧化钛进行了表征，证实了二氧化钛表面存在高度晶化的混合单层/少层h-BN纳米薄片。钝化有助于减少二氧化钛/染料/电解液界面上的电子-空穴复合。H-BN钝化处理后的DSSC在低正向偏置区表现出较低的暗饱和电流，在高正向偏置区表现出较高的饱和电流，这表明在不阻碍材料界面载流子输运的情况下，界面质量得到了很大的改善。实验结果表明，与高k薄膜介质相比，这种新型的2D层状绝缘体具有结晶度高、无自终止/无悬键原子面等材料特性，可用于太阳能电池的有效表面钝化。
A two-dimensional layered insulator, hexagonal boron nitride (h-BN), is demonstrated as a new class of surface passivation materials in dye-sensitized solar cells (DSSCs) to reduce interfacial carrier recombination. We observe ~57% enhancement in the photo-conversion efficiency of the DSSC utilizing h-BN coated semiconductor TiO2 as compared with the device without surface passivation. The h-BN coated TiO2 is characterized by Raman spectroscopy to confirm the presence of highly crystalline, mixed monolayer/few-layer h-BN nanoflakes on the surface of TiO2. The passivation helps to minimize electron-hole recombination at the TiO2/dye/electrolyte interfaces. The DSSC with h-BN passivation exhibits significantly lower dark saturation current in the low forward bias region and higher saturation in the high forward bias region, respectively, suggesting that the interface quality is largely improved without impeding carrier transport at the material interface. The experimental results reveal that the emerging 2D layered insulator could be used for effective surface passivation in solar cell applications attributed to desirable material features such as high crystallinity and self-terminated/dangling-bond-free atomic planes as compared with high-k thin-film dielectrics.