High open-circuit voltage in single-crystalline n-type SnS/MoO3 photovoltaics
Issei Suzuki,
Zexin Lin,
Taichi Nogami,
Sakiko Kawanishi,
Binxiang Huang,
Andreas Klein,
Takahisa Omata
Affiliations
Issei Suzuki
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Zexin Lin
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Taichi Nogami
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Sakiko Kawanishi
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Binxiang Huang
Department of Materials and Earth Science, Electronic Structure of Materials, Technical University of Darmstadt, Otto-Berndt-Str. 3, 64287 Darmstadt, Germany
Andreas Klein
Department of Materials and Earth Science, Electronic Structure of Materials, Technical University of Darmstadt, Otto-Berndt-Str. 3, 64287 Darmstadt, Germany
Takahisa Omata
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
It has been recently reported that n-type single crystalline SnS exhibits a large band bending (∼1 eV) at the interface with MoO3, which is a large work function material. In this study, we applied this interface to solar cells for the first time and evaluated its photovoltaic properties. The highest VOC achieved was 437 mV. Although this value is the highest ever recorded for SnS solar cells, it was lower than the expected value of 700–800 mV. The highest power conversion efficiency (PCE) was 4.4%. Based on an analysis of the device parameters, we propose methods for improving the device performance, including VOC, the short-circuit current, and PCE. The carrier-collection length of the n-type SnS single crystals was estimated to be ∼200 nm based on the external quantum efficiency measurements. Therefore, this study demonstrates that the VOC of SnS solar cells can be improved by fabricating a junction with MoO3 thin films.
