Sodium-assisted passivation of grain boundaries and defects in Cu2ZnSnSe4 thin films
- 주제(기타) Chemistry, Physical
- 주제(기타) Physics, Atomic, Molecular & Chemical
- 설명문(일반) [Kim, Juran; Kim, Gee Yeong; Trang, Thi Thu Nguyen; Yoon, Seokhyun; Jo, William] Ewha Womans Univ, Dept Phys, Seoul 03760, South Korea; [Kim, Juran; Kim, Gee Yeong; Trang, Thi Thu Nguyen; Yoon, Seokhyun; Jo, William] Ewha Womans Univ, New & Renewable Energy Res Ctr NREC, Seoul 03760, South Korea; [Kim, Yoon-Koo; Lee, Seung-Yong; Kim, Miyoung] Seoul Natl Univ, Dept Mat Sci & Engn, Seoul 08826, South Korea; [Cho, Dae-Hyung; Chung, Yong-Duck] Elect & Telecommun Res Inst ETRI, ICT Mat Res Grp, Daejeon 34129, South Korea; [Lee, Je-Ho; Seong, Maeng-Je] Chung Ang Univ, Dept Phys, Seoul 06974, South Korea
- 등재 SCIE, SCOPUS
- 발행기관 ROYAL SOC CHEMISTRY
- 발행년도 2020
- 총서유형 Journal
- URI http://www.dcollection.net/handler/ewha/000000168722
- 본문언어 영어
- Published As https://dx.doi.org/10.1039/c9cp06537g
- PubMed https://pubmed.ncbi.nlm.nih.gov/32226986
초록/요약
The long stagnation of the photo-conversion efficiency of kesterites below 13% is a source of frustration in the scientific community. In this study, we investigated the effects of sodium on the passivation of grain boundaries and defects in Cu2ZnSnSe4 (CZTSe) grown on a soda-lime glass (SLG) and borosilicate (BS) glass. Because BS glass does not inherently contain sodium, we placed a thin layer of NaF between CZTSe and Mo. The composition of the samples is Cu-poor and Zn-rich. The distribution of sodium and its contributions to phase formation and defects were examined by cross-sectional energy-dispersive X-ray profiling, Raman scattering spectroscopy and imaging, surface potential and photoluminescence. From the experimental results, it can be strongly claimed that sodium ions segregate predominantly near the grain boundaries and reduce Cu-Zn-related defects. These local surface imaging analyses provided the exact locations of the secondary phases. In particular, the photo-assisted scanning probe method enabled us to observe the changes in the optoelectrical properties of the thin films and the carrier behavior within the materials. Further studies with distinct alkali ions and optimal processing conditions will pave a way to improve the performance of kesterite solar cells.
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