Superomniphobic, Flexible Polymer with High Transparency and Ultrahigh Haze
Flexible optoelectronics are emerging as an exciting new technology for use in flexible versions of traditional rigid displays, such as smartphones, tablets, and e-paper, as well as new wearables, RFID tags, artificial skin, and the Internet of Things. The optical properties of the protective coverings for these new optoelectronics are critical, as light needs to be coupled into or out of the active region of the device through a transparent material; plastic is a popular choice and polyethylene terephthalate (PET), in particular, is often selected for its tolerance to temperature variance and resistance to solvents in addition to its high optical transmittance. For optoelectronic applications such as organic-light emitting diodes (OLEDs) and solar cells, it is desirable to have a covering with both high transmittance as well as high haze, which increases light scattering and leads to increased photon out-coupling or in-coupling efficiency. Thus far, the options that fit these conditions involve various lithographic steps or nanomaterials that increase cost and production complexity, or tradeoff high haze for lower transmission. A sought-after combination of both transmission and haze over 90% has yet to be demonstrated in flexible PET materials.
Description
Researchers have developed a superomniphobic PET with both high transparency and high haze, with values at the 550 nm wavelength of 86.0% and 98.5%, respectively. The omniphobicity repels both water and oil-based fluids, lending it a self-cleaning capability and preventing contamination of photovoltaic systems in various environments. The high transparency eliminates reflection losses, improving performance, while the high haze enhances the capability to capture incident photons. This superomniphobic, high transparency, ultrahigh haze PET will lead to exciting new developments in solar cell systems, camera lenses, eyeglasses, windows, smartphones, wearables, and so much more.Applications
· Flexible versions of traditionally rigid displays, such as smartphones and tablets· New wearables
· RFID tags
· Artificial skin
· Solar cells
· Camera lenses
· Eyeglasses
· Internet of Things
Advantages
· High transparency without structuring haze, and vice versa· Superomniphobic surface repels water- and oil-based liquids
· Self-cleaning
· Eliminates reflection losses, improving performance
· Increases photon capture rate, improving efficiency