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 A.
AU - Walsh, Aron
PY - 2014/1/13
Y1 - 2014/1/13
N2 - Kesterite semiconductors, particularly Cu2ZnSnS4 (CZTS), have attracted attention for thin-film solar cells. We investigate the incorporation of Fe into CZTS to form the Cu2(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 Cu2ZnSnS4 (CZTS), have attracted attention for thin-film solar cells. We investigate the incorporation of Fe into CZTS to form the Cu2(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.
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U2 - 10.1063/1.4862030
DO - 10.1063/1.4862030
M3 - Article
AN - SCOPUS:84893092433
SN - 0003-6951
VL - 104
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 2
M1 - 021912
ER -