TY - JOUR
T1 - From kesterite to stannite photovoltaics
T2 - Stability and band gaps of the Cu2 (Zn, Fe) SnS4 alloy
AU - Shibuya, Taizo
AU - Goto, Yosuke
AU - Kamihara, Yoichi
AU - Matoba, Masanori
AU - Yasuoka, Kenji
AU - Burton, Lee
AU - Walsh, A
PY - 2014/1
Y1 - 2014/1
N2 - Kesterite semiconductors, particularly Cu 2ZnSnS4 (CZTS), have attracted attention for thin-film solar cells. We investigate the incorporation of Fe into CZTS to form the Cu 2(Zn,Fe)SnS4 solid-solution for tuning the lattice spacing and band gap. First-principles calculations confirm a phase transition from kesterite (Zn-rich) to stannite (Fe-rich) at Fe/Zn ∼ 0.4 . The exothermic enthalpy of mixing is consistent with the high solubility of Fe in the lattice. There is a linear band-gap bowing for each phase, which results in a blue-shift of photo-absorption for Fe-rich alloys due to the confinement of the conduction states. We propose compositions optimal for Si tandem cells.
AB - Kesterite semiconductors, particularly Cu 2ZnSnS4 (CZTS), have attracted attention for thin-film solar cells. We investigate the incorporation of Fe into CZTS to form the Cu 2(Zn,Fe)SnS4 solid-solution for tuning the lattice spacing and band gap. First-principles calculations confirm a phase transition from kesterite (Zn-rich) to stannite (Fe-rich) at Fe/Zn ∼ 0.4 . The exothermic enthalpy of mixing is consistent with the high solubility of Fe in the lattice. There is a linear band-gap bowing for each phase, which results in a blue-shift of photo-absorption for Fe-rich alloys due to the confinement of the conduction states. We propose compositions optimal for Si tandem cells.
UR - http://www.scopus.com/inward/record.url?scp=84893092433&partnerID=8YFLogxK
UR - http://dx.doi.org/10.1063/1.4862030
U2 - 10.1063/1.4862030
DO - 10.1063/1.4862030
M3 - Article
SN - 0003-6951
VL - 104
SP - 021912
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 2
M1 - 021912
ER -