Revealing the Role of Potassium Treatment in CZTSSe Thin Film Solar Cells

Li, Wenjie1; Su, Zhenghua3; Tan, Joel Ming Rui1,2; Chiam, Sing Yang4; Seng, Hwee Leng4; Magdassi, Shlomo5; Wong, Lydia Helena1,2

2017-05-23

10.1021/acs.chemmater.7b00418

CHEMISTRY OF MATERIALS   影响因子和分区

0897-4756

1520-5002

Potassium (K) post-treatment on CIGSSe has been shown to yield the highest efficiency reported to date. However, very little is known on the effect of K doping in CZTSSe and the mechanism behind the efficiency improvement. Here we reveal the mechanism by which K enhances the charge separation in CZTSSe. We show that K accumulates at the CdS/CZTSSe, passivating the recombination at the front interface and improving carrier collection. K is also found to accumulate at the CZTSSe/Mo interface and facilitates the diffusion of Cd into the absorber which affects the morphology and grain growth of CZTSSe. As revealed by the C-V, external quantum efficiency, and color J-V test, K doping significantly increases the carrier density, improves carrier collection, and passivates the front interface and grain boundaries, leading to the enhancement of V-oc and J(sc). The average power conversion efficiency has been promoted from 5% to above 7%, and the best 7.78% efficiency has been achieved for the 1.5 mol % K-doped CZTSSe device. This work offers some new insights into the K doping effects on CZTSSe via solution-based approach and demonstrates the potential of facile control of K doping for further improvement of CZTSSe thin film solar cells.

SCI ; EI

英语

其他

Prime Minister's Office, Brunei Darussalam[] ; National Research Foundation[]

Chemistry ; Materials Science

Chemistry, Physical ; Materials Science, Multidisciplinary

WOS:000402498000016

AMER CHEMICAL SOC

20172203709748

Cadmium sulfide ; Efficiency ; Grain boundaries ; Grain growth ; II-VI semiconductors ; Potassium ; Semiconductor doping ; Solar cells ; Thin films

Alkali Metals:549.1 ; Solar Cells:702.3 ; Semiconducting Materials:712.1 ; Chemical Products Generally:804 ; Production Engineering:913.1 ; Crystal Growth:933.1.2

MATERIALS SCIENCE

Web of Science

1.Nanyang Technol Univ, Energy Res Inst NTU ERI N, Campus Res Excellence & Technol Enterprise, Singapore 637553, Singapore
2.Nanyang Technol Univ, Sch Mat Sci & Engn, Singapore 639798, Singapore
3.South Univ Sci & Technol China, Phys Dept, Shenzhen 518055, Peoples R China
4.ASTAR, Inst Mat Res & Engn, 2 Fusionopolis Way, Innovis 138634, Singapore
5.Hebrew Univ Jerusalem, Ctr Nanosci & Nanotechnol, Edmond J Safra Campus, IL-91904 Jerusalem, Israel

Li, Wenjie,Su, Zhenghua,Tan, Joel Ming Rui,et al. Revealing the Role of Potassium Treatment in CZTSSe Thin Film Solar Cells[J]. CHEMISTRY OF MATERIALS,2017,29(10):4273-4281.

Li, Wenjie.,Su, Zhenghua.,Tan, Joel Ming Rui.,Chiam, Sing Yang.,Seng, Hwee Leng.,...&Wong, Lydia Helena.(2017).Revealing the Role of Potassium Treatment in CZTSSe Thin Film Solar Cells.CHEMISTRY OF MATERIALS,29(10),4273-4281.

Li, Wenjie,et al."Revealing the Role of Potassium Treatment in CZTSSe Thin Film Solar Cells".CHEMISTRY OF MATERIALS 29.10(2017):4273-4281.