Efficient and Stable Fiber Dye-Sensitized Solar Cells Based on Solid-State Li-TFSI Electrolytes with 4-Oxo-TEMPO Derivatives

Pyeongje An; Jae Ho Kim; Myeonghwan Shin; Sukyeong Kim; Sungok Cho; Chaehyun Park; Geonguk Kim; Hyung Woo Lee; Jin Woo Choi; Chuljin Ahn; Myungkwan Song

doi:10.3390/nano12132309

Efficient and Stable Fiber Dye-Sensitized Solar Cells Based on Solid-State Li-TFSI Electrolytes with 4-Oxo-TEMPO Derivatives

Nanomaterials (Basel). 2022 Jul 5;12(13):2309. doi: 10.3390/nano12132309.

Authors

Pyeongje An^{1

2}, Jae Ho Kim¹, Myeonghwan Shin³, Sukyeong Kim¹, Sungok Cho¹, Chaehyun Park^{1

2}, Geonguk Kim^{1

2}, Hyung Woo Lee^{2

4}, Jin Woo Choi¹, Chuljin Ahn³, Myungkwan Song¹

Affiliations

¹ Department of Energy & Electronic Materials, Korea Institute of Materials Science (KIMS), Changwon 51508, Korea.
² Department of Nano Fusion Technology, Pusan National University, Busan 46241, Korea.
³ Department of Biology and Chemistry, Changwon National University, Changwon 51140, Korea.
⁴ Department of Nanoenergy Engineering and Research Center of Energy Convergence Technology, Pusan National University, Busan 46241, Korea.

Abstract

Fiber-shaped dye-sensitized solar cells (FDSSCs) with flexibility, weavablity, and wearability have attracted intense scientific interest and development in recent years due to their low cost, simple fabrication, and environmentally friendly operation. Since the Grätzel group used the organic radical 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as the redox system in dye-sensitized solar cells (DSSCs) in 2008, TEMPO has been utilized as an electrolyte to further improve power conversion efficiency (PCE) of solar cells. Hence, the TEMPO with high catalyst oxidant characteristics was developed as a hybrid solid-state electrolyte having high conductivity and stability structure by being integrated with a lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) film for FDSSCs. The optimized 4-Oxo TEMPO (OX) based solid-state FDSSC (SS-FDSSC) showed the PCE of up to 6%, which was improved by 34.2% compared to that of the reference device with 4.47%. The OX-enhanced SS-FDSSCs reduced a series resistance (R_s) resulting in effective electron extraction with improved short-circuit current density (J_SC), while increasing a shunt resistance (R_sh) to prevent the recombination of photo-excited electrons. The result is an improvement in a fill factor (FF) and consequently a higher value for the PCE.

Keywords: TEMPO derivatives; dye-sensitized solar cells; fiber-shaped solar cells; solid-state Li-TFSI electrolyte.

Grants and funding

This research was supported by the Fundamental Research Program (PNK 8080) of the Korea Institute of Materials Science (KIMS) and by a National Research Foundation (NRF) grant funded by the Korean government (No. 2021R1A2C2014192).