GaAs nanowire array solar cells with axial p-i-n junctions

Maoqing Yao, Ningfeng Huang, Sen Cong, Chun Yung Chi, M. Ashkan Seyedi, Yen Ting Lin, Yu Cao, Michelle L. Povinelli, P. Daniel Dapkus, Chongwu Zhou

Research output: Contribution to journalArticle

115 Scopus citations


Because of unique structural, optical, and electrical properties, solar cells based on semiconductor nanowires are a rapidly evolving scientific enterprise. Various approaches employing III-V nanowires have emerged, among which GaAs, especially, is under intense research and development. Most reported GaAs nanowire solar cells form p-n junctions in the radial direction; however, nanowires using axial junction may enable the attainment of high open circuit voltage (Voc) and integration into multijunction solar cells. Here, we report GaAs nanowire solar cells with axial p-i-n junctions that achieve 7.58% efficiency. Simulations show that axial junctions are more tolerant to doping variation than radial junctions and lead to higher Voc under certain conditions. We further study the effect of wire diameter and junction depth using electrical characterization and cathodoluminescence. The results show that large diameter and shallow junctions are essential for a high extraction efficiency. Our approach opens up great opportunity for future low-cost, high-efficiency photovoltaics.

Original languageEnglish (US)
Pages (from-to)3293-3303
Number of pages11
JournalNano Letters
Issue number6
StatePublished - Jun 11 2014
Externally publishedYes



  • Nanowires
  • axial junction
  • gallium arsenide
  • solar cells

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Cite this

Yao, M., Huang, N., Cong, S., Chi, C. Y., Seyedi, M. A., Lin, Y. T., Cao, Y., Povinelli, M. L., Dapkus, P. D., & Zhou, C. (2014). GaAs nanowire array solar cells with axial p-i-n junctions. Nano Letters, 14(6), 3293-3303.