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2025 Vol.45, Issue 6 Preview Page

Research Article

Fluorine-Free Transparent Backsheets for Low-Carbon Footprint Photovoltaic Modules

저탄소 태양광 모듈을 위한 비불소계 투명 백시트

Da Young Kwon1
,
Yerang Park1
,
Jae-Ik Han1
,
Nochang Park2
,
Soohyun Bae3
,
Kyung-Soo Kim4
,
Young-Joo Eo4
,
Gi-Hwan Kang4
,
Yonghwan Lee5*
권 다영1
,
박 예랑1
,
한 재익1
,
박 노창2
,
배 수현3
,
김 경수4
,
어 영주4
,
강 기환4
,
이 용환5*
1Researcher, Advanced Batteries Research Center, Korea Electronics Technology Institute
2Chief Researcher, Advanced Batteries Research Center, Korea Electronics Technology Institute
3Senior Researcher, Photovoltaic Research Department, Korea Institute of Energy Research
4Principal Researcher, Photovoltaic Research Department, Korea Institute of Energy Research
5Principal Researcher, Advanced Batteries Research Center, Korea Electronics Technology Institute
1한국전자기술연구원 차세대전지연구센터, 연구원
2한국전자기술연구원 차세대전지연구센터, 수석연구원
3한국에너지기술연구원 태양광연구단, 선임연구원
4한국에너지기술연구원 태양광연구단, 책임연구원
5한국전자기술연구원 차세대전지연구센터, 책임연구원
*Corresponding Author
30 December 2025. pp. 71-79
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Abstract

Fluorine-free transparent photovoltaic backsheets were developed via dip-coating polyethylene terephthalate (PET) films with perhydropolysilazane (PHPS), which were subsequently converted to a SiOxNy-based inorganic coating layer on the PET surface. Fourier-transform infrared (FT-IR) spectroscopy confirmed the formation of Si–O, Si–N, and Si–OH bonds, effectively converting the PHPS precursor into a robust SiOxNy network. UV–Vis measurements revealed that the optical transmittance of the coated films was high (>88%), ensuring optical suitability for photovoltaic transparent backsheet applications. The water vapor transmission rate (WVTR) measurements demonstrated that the moisture permeability (<2 g/m2·day) was lower than that of the untreated PET films, whereas the adhesion tests confirmed strong interfacial bonding between the SiOxNy-coated PET film and the encapsulant. Furthermore, the films retained high transparency and strong moisture barrier performance after accelerated aging under pressure-cooker test (PCT) conditions and UV irradiation, confirming their high durability and environmental stability. Overall, SiOxNy-coated PET films are a sustainable, transparent, and high-performance alternative to conventional fluorine-based backsheets for low-carbon photovoltaic modules.

Keywords
low-carbon material
photovoltaic module
fluorine-free
transparent backsheet
키워드
저탄소 소재
태양광 모듈
비불소계
투명 백시트
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Information
  • Publisher :Korean Solar Energy Society
  • Publisher(Ko) :한국태양에너지학회
  • Journal Title :Journal of the Korean Solar Energy Society
  • Journal Title(Ko) :한국태양에너지학회 논문집
  • Volume : 45
  • No :6
  • Pages :71-79
  • Received Date : 2025-10-22
  • Revised Date : 2025-11-27
  • Accepted Date : 2025-11-28
  • DOI :https://doi.org/10.7836/kses.2025.45.6.071
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