In:
Advanced Materials, Wiley, Vol. 32, No. 52 ( 2020-12)
Abstract:
Kesterite‐based Cu 2 ZnSn(S,Se) 4 semiconductors are emerging as promising materials for low‐cost, environment‐benign, and high‐efficiency thin‐film photovoltaics. However, the current state‐of‐the‐art Cu 2 ZnSn(S,Se) 4 devices suffer from cation‐disordering defects and defect clusters, which generally result in severe potential fluctuation, low minority carrier lifetime, and ultimately unsatisfactory performance. Herein, critical growth conditions are reported for obtaining high‐quality Cu 2 ZnSnSe 4 absorber layers with the formation of detrimental intrinsic defects largely suppressed. By controlling the oxidation states of cations and modifying the local chemical composition, the local chemical environment is essentially modified during the synthesis of kesterite phase, thereby effectively suppressing detrimental intrinsic defects and activating desirable shallow acceptor Cu vacancies. Consequently, a confirmed 12.5% efficiency is demonstrated with a high V OC of 491 mV, which is the new record efficiency of pure‐selenide Cu 2 ZnSnSe 4 cells with lowest V OC deficit in the kesterite family by E g / q ‐ V oc. These encouraging results demonstrate an essential route to overcome the long‐standing challenge of defect control in kesterite semiconductors, which may also be generally applicable to other multinary compound semiconductors.
Type of Medium:
Online Resource
ISSN:
0935-9648
,
1521-4095
DOI:
10.1002/adma.202005268
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
1474949-X