Plasmon-induced photonic and energy-transfer enhancement of solar water splitting by a hematite nanorod array
Plasmon-induced photonic and energy-transfer enhancement of solar water splitting by a hematite nanorod array
复制标题
DOI：
10.1038/ncomms3651
复制
发表时间：
2013-10-01
影响因子：
16.6
通讯作者：
Wu, Nianqiang
中科院分区：
文献类型：
--
作者：
Li, Jiangtian;Cushing, Scott K.;Wu, Nianqiang
等离子体金属纳米结构为提高半导体的太阳能转换效率提供了一条有前途的途径。在这里，我们表明，将赤铁矿纳米棒阵列并入等离子体金纳米孔阵列图案中显著提高了光电化学水裂解性能，导致在模拟太阳辐射下，在0.23V的偏压下相对于Ag垂直条AgCl的光电流增加约10倍。等离子体激元诱导的共振能量转移负责在带边以下的能量处的增强，而在赤铁矿的吸收带边以上，表面等离子体激元极化激元在纳米棒内发射导波模式，其中纳米棒充当微型光纤，增强光吸收。此外，强的局部等离子体激元场可以抑制光电化学电池中的赤铁矿纳米棒光阳极中的电荷复合。我们的研究结果可以提供一种通用的方法来克服薄半导体纳米结构的低光吸收和光谱利用率，同时进一步减少电荷复合损耗。
Plasmonic metal nanostructures offer a promising route to improve the solar energy conversion efficiency of semiconductors. Here we show that incorporation of a hematite nanorod array into a plasmonic gold nanohole array pattern significantly improves the photoelectrochemical water splitting performance, leading to an approximately tenfold increase in the photocurrent at a bias of 0.23V versus Ag vertical bar AgCl under simulated solar radiation. Plasmon-induced resonant energy transfer is responsible for enhancement at the energies below the band edge, whereas above the absorption band edge of hematite, the surface plasmon polariton launches a guided wave mode inside the nanorods, with the nanorods acting as miniature optic fibres, enhancing the light absorption. In addition, the intense local plasmonic field can suppress the charge recombination in the hematite nanorod photoanode in a photoelectrochemical cell. Our results may provide a general approach to overcome the low optical absorption and spectral utilization of thin semiconductor nanostructures, while further reducing charge recombination losses.