Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Development of Electret to Improve Output and Stability of Triboelectric Nanogenerator

마찰대전 나노발전기의 출력 및 안정성 향상을 위한 일렉트렛 개발

  • Kam, Dongik (Department of Mechanical Engineering, Kyung Hee University) ;
  • Jang, Sunmin (Department of Mechanical Engineering, Kyung Hee University) ;
  • Yun, Yeongcheol (Department of Mechanical Engineering, Kyung Hee University) ;
  • Bae, Hongeun (Department of Mechanical Engineering, Kyung Hee University) ;
  • Lee, Youngjin (Department of Mechanical Engineering, Kyung Hee University) ;
  • Ra, Yoonsang (Department of Mechanical Engineering, Kyung Hee University) ;
  • Cho, Sumin (Department of Mechanical Engineering, Kyung Hee University) ;
  • Seo, Kyoung Duck (Department of Mechanical Engineering, Wonkwang University) ;
  • Cha, Kyoung Je (Smart Manufacturing Technology R&D Group, KITECH) ;
  • Choi, Dongwhi (Department of Mechanical Engineering, Kyung Hee University)
  • 감동익 (경희대학교 기계공학과) ;
  • 장순민 (경희대학교 기계공학과) ;
  • 윤영철 (경희대학교 기계공학과) ;
  • 배홍은 (경희대학교 기계공학과) ;
  • 이영진 (경희대학교 기계공학과) ;
  • 라윤상 (경희대학교 기계공학과) ;
  • 조수민 (경희대학교 기계공학과) ;
  • 서경덕 (원광대학교 기계공학과) ;
  • 차경제 (한국생산기술연구원 스마트제조기술연구그룹) ;
  • 최동휘 (경희대학교 기계공학과)
  • Received : 2021.09.07
  • Accepted : 2021.10.01
  • Published : 2022.02.01
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Abstract

With the rapid development of ultra-small and wearable device technology, continuous electricity supply without spatiotemporal limitations for driving electronic devices is required. Accordingly, Triboelectric nanogenerator (TENG), which utilizes static electricity generated by the contact and separation of two different materials, is being used as a means of effectively harvesting various types of energy dispersed without complex processes and designs due to its simple principle. However, to apply the TENG to real life, it is necessary to increase the electrical output. In addition, stable generation of electrical output, as well as increase in electrical output, is a task to be solved for the commercialization of TENG. In this study, we proposed a method to not only improve the output of TENG but also to stably represent the improved output. This was solved by using the contact layer, which is one of the components of TENG, as an electret for improved output and stability. The utilized electret was manufactured by sequentially performing corona charging-thermal annealing-corona charging on the Fluorinated ethylene propylene (FEP) film. Electric charges artificially injected due to corona charging enter a deep trap through the thermal annealing, so an electret that minimizes charge escape was fabricated and used in TENG. The output performance of the manufactured electret was verified by measuring the voltage output of the TENG in vertical contact separation mode, and the electret treated to the corona charging showed an output voltage 12 times higher than that of the pristine FEP film. The time and humidity stability of the electret was confirmed by measuring the output voltage of the TENG after exposing the electret to a general external environment and extreme humidity environment. In addition, it was shown that it can be applied to real-life by operating the LED by applying an electret to the clap-TENG with the motif of clap.

초소형, 웨어러블 기기 기술의 빠른 발전에 따라, 전자기기 구동을 위한 시공간적인 제한이 없는 지속적인 전기 공급을 필요로 한다. 이에 따라, 두 가지 다른 재료의 접촉과 분리로 만들어지는 정전기를 활용하는 마찰대전 나노발전기(Triboelectric nanogenerator, TENG)는 간단한 원리 덕분에, 복잡한 과정 및 설계 없이도 자연에서 버려지는 다양한 형태의 에너지들을 효과적으로 수확하는 수단으로 활용되고 있다. 하지만, TENG의 실생활의 적용을 위해서는 전기적 출력의 증가가 필요하다. 또한, 전기적 출력의 증가뿐만 아니라 전기적 출력의 안정적인 발생은 TENG의 상용화를 위해서 해결해야 될 과제이다. 본 연구에서는 TENG의 출력을 향상시킬 뿐만 아니라, 향상된 출력을 안정적으로 나타낼 수 있는 방법을 제안하였다. 출력의 향상 및 안정성을 위해서 TENG 구성 요소 중 하나인 접촉층을 일렉트렛으로 사용하였다. 활용된 일렉트렛은 Fluorinated ethylene propylene (FEP) 필름에 코로나 차징과 열처리 과정을 순차적으로 진행함으로써 제작되었다. 코로나 차징으로 인해 인위적으로 주입된 전하가 열처리 과정에 의해서 깊은 트랩으로 들어가게 되어 전하의 이탈 현상이 최소화된 일렉트렛을 제작하고 이를 TENG 제작에 활용하였다. 제작된 일렉트렛의 출력 성능은 수직 접촉 분리 모드 TENG의 전압 출력을 측정함으로써 검증되었고, 코로나 차징 과정을 거친 일렉트렛은 어떠한 처리도 되지 않은 FEP 필름에 대비 12배 높은 출력 전압을 나타냈다. 일렉트렛의 시간 및 습도 안정성은 일반 외부 환경 및 극한의 습도 환경에 일렉트렛을 노출시킨 후, TENG의 출력 전압을 측정함으로써 확인되었다. 또한, 박수를 모티브로 한 Clap-TENG에 일렉트렛을 적용하여 LED를 작동시킴으로써 실생활에 적용할 수 있음을 보여주었다.

Keywords

Acknowledgement

본 연구는 산업통상자원부와 한국산업기술진흥원의 "지역특화산업육성사업"(과제번호 S2913296)으로 수행된 연구결과 입니다.

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