硅BC8量子点太阳能电池中的多重激子效应

摘要

多重激子效应是指在纳米半导体晶体中,量子点吸收一个高能光子而产生多个电子-空穴对的过程,该效应可以提高单结太阳电池能量转换效率.利用碰撞电离机制和费米统计模型计算了工作温度300 K的单结硅BC8量子点太阳能电池在AM1.5G太阳光谱下的能量转换效率.对于波长在280～580 nm的入射光,多重激子效应可以大幅增强硅BC8量子点直径d>5.0 nm的量子点太阳电池的能量转换效率.硅纳米量子点的直径d=6.3～6.4 nm时,最大能量转换效率为51.6％.%Multiple exciton generation( MEG) is a process whereby multiple electron-hole pairs or excitons are produced upon absorption of a single photon in semiconductor quantum dots ( QDs ) . This effect represents a promising route to increase solar conversion efficiencies in single-junction photovoltaic cells. MEG in Si BC8 QDs is based on impact ionization and statistical Fermi. The power conversion efficiency for Si QDs solar cells was calculated under AM1 . 5 G solar spectrum with the cell temperature at 300 K. For the incident wavelength of 280-580 nm, the power conversion efficiency can be improved by MEG effect for d>5. 0 nm Si QDs. For Si BC8 QDs with d=6. 3-6. 4 nm, the maximum energy conversion efficiency is 51. 6％.