Flexible Multi-Color Electroluminescent Devices on a Cellulose Nanocrystal Platform

• Author / Creator

  Amir Masoud Badkoobehhezaveh

• Cellulose nanocrystals (CNCs) are recognized as special nanomaterials extracted from the most plentiful and almost unlimited natural polymer, cellulose. This nanomaterial is inherently renewable, biodegradable, sustainable, nontoxic, and earth abundant. CNCs recently have received significant interest due to their mechanical, optical, chemical, and rheological properties. CNC as an organic compound is extremely versatile, being used as a reinforcing agent or can be chemically or physically modified for different applications. Additionally, CNCs have been realized as a cost-effective nanomaterial in an industrial-scale production.
  This thesis is focused on making the intrinsically insulating CNCs, highly conductive to be used in electroluminescent applications. In this work, flexible electroluminescent devices (FELDs) are demonstrated using environmentally-friendly cellulose nanocrystals substrates having a silver nanowire conductive network. The CNC sheets, with drop-casted silver nanowires (Ag NWs), act as highly transparent conductive electrodes for an electroluminescent layer (a phosphorescent ink containing Cu/Br-doped ZnS microparticles). This phosphorescent device requires operating voltages as low as 7 V and achieves a high luminance of up to 43 Cd/m2 (at 50 V). Furthermore, through impregnating the CNC host material with Rhodamine 6G or Thiazol Yellow G, blue, turquoise, green and purple light emission having a broad (400 nm to 650 nm) luminescence spectrum were obtained. We envision this device, which employs earth abundant, cost-effective, and recyclable materials, will lead to advancements in the areas of electronics and lighting technology.
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  To the best of our knowledge, this work is among the very few pioneering studies that explore the potential of CNC sheets drop-casted by Ag NWs as highly conductive and flexible transparent substrates for electroluminescent device applications. This thesis presents details for fabricating flexible and transparent CNC sheets from CNC powders and the synthesis of long Ag NWs for FELDs.

• Subjects / Keywords

  • Electroluminescent device
  • Flexible electronics
  • Cellulose nano-crystals
  • Silver nanowires
  • light emitting device

• Graduation date

  Fall 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-wvxa-cb93

• License

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