Interface engineering for highly efficient graphene-on-silicon Schottky junction solar cells by introducing a hexagonal boron nitride interlayer
Interface engineering for highly efficient graphene-on-silicon Schottky junction solar cells by introducing a hexagonal boron nitride interlayer
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DOI：
10.1016/j.nanoen.2016.08.028
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发表时间：
2016-10
期刊：
影响因子：
17.6
通讯作者：
J. Meng;Xin Liu;Xingwang Zhang;Yue Zhang;Haolin Wang;Z. Yin;Zhang Yongzhe;Heng Liu;J. You-J.
中科院分区：
文献类型：
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作者：
J. Meng;Xin Liu;Xingwang Zhang;Yue Zhang;Haolin Wang;Z. Yin;Zhang Yongzhe;Heng Liu;J. You-J.
硅上石墨烯（Gr/Si）肖特基结太阳能电池作为低成本光伏应用的有前途的候选者最近吸引了相当大的兴趣。但Gr/Si电池的效率仍远低于晶体Si太阳电池，这主要归因于Gr/Si肖特基势垒较低导致的载流子界面复合。本文中，引入少层六方氮化硼（h-BN）来设计Gr/Si界面以改善器件性能。由于h-BN的独特性质和与Si适当的能带排列，h-BN可以作为有效的电子阻挡/空穴传输层，从而抑制了界面复合，并显著提高了开路电压。另一方面，太阳能电池的串联电阻由于h-BN上石墨烯的导电性的改善而降低，导致短路电流密度的增加。此外，通过使用直接生长的Gr/h-BN异质结构，可以消除由逐层转移过程引起的界面缺陷和污染。结果表明，采用h-BN中间层和石墨烯与Au纳米颗粒和HNO3共掺杂的方法制备的Gr/h-BN/Si太阳能电池的最大转换效率为10.93%，显示了新型Gr/h-BN/Si太阳能电池的巨大潜力。
Graphene-on-silicon (Gr/Si) Schottky junction solar cells have recently attracted considerable interest as promising candidates for low-cost photovoltaic applications. However, the efficiency of Gr/Si cells is still much lower than that of crystalline Si solar cells, which is mainly attributed to the interface recombination of carriers due to the low Gr/Si Schottky barrier. Herein, a few-layer hexagonal boron nitride (h-BN) is introduced to engineer the Gr/Si interface for improving device performance. The h-BN can act as an effective electron-blocking/hole-transporting layer due to its unique properties and appropriate band alignment with Si, and thus the interface recombination was suppressed and the open circuit voltage was remarkably increased. On the other hand, the series resistance of solar cells decreases due to an improving conductivity of graphene on h-BN, leading to an increased short circuit current density. Furthermore, the interface defects and contamination arising from the layer-by-layer transfer process can be eliminated by using a directly grown Gr/h-BN heterostructure. As a result, a maximum efficiency of 10.93% was achieved by combining h-BN interlayer and co-doping of graphene with Au nanoparticles and HNO3, which shows the great potential of the novel Gr/h-BN/Si solar cells.