Open AccessDesign of μc-Si:H/a-Si:H coaxial tandem single-nanowire solar cells considering photocurrent matching
Author(s) -
Guoyang Cao,
Xiao Feng Li,
Yaohui Zhan,
Shaolong Wu,
Aixue Shang,
Cheng Zhang,
Zhenhai Yang,
Xiongfei Zhai
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.0a1761
Subject(s) - photocurrent , tandem , radius , nanowire , materials science , coaxial , energy conversion efficiency , open circuit voltage , solar cell , core (optical fiber) , optoelectronics , optics , voltage , physics , telecommunications , computer security , quantum mechanics , computer science , composite material
The single nanowire solar cells (SNSCs) with radial junctions are expected to show the superiority in efficient carrier collection benefited from the largely shortened junction length. Considering that the conversion efficiency of the existing SNSCs is still limited due to the low operation voltage, we design μc-Si:H(core)/a-Si:H(shell) radial tandem SNSCs, giving much attention to the intrinsic optical and electrical properties. The core and shell cells are carefully engineered in order to realize the photocurrent matching. It is found that under matching condition the radius of the entire cell (R) shows linear dependence on the radius of the core cell (r), i.e., R ~1.2r. Under an optimal design of the tandem cell, the open-circuit voltage (photoconversion efficiency) is increased by 160% (34% relative) compared to the equivalent-size μc-Si:H SNSCs.