White Light Emission from Vegetable Extracts
The optimized mixture of two suitably chosen plant extracts using acidic ethanol, aided by a FRET cascade from polyphenolics to curcumin to anthocyanins, generates almost pure white light, with CIE values of (0.35, 0.33) in solution, (0.26, 0.33) in gelatin gel and (0.33, 0.25) in PVA film. The color temperature of the WLE is conveniently tunable by simply adjusting the concentrations of the component emitters. The primary emitting pigments responsible for contributing to WLE are polyphenol s and anthocyanins from pomegranate, and curcumin from turmeric. WLE from such cheap and nature-friendly resources could be important in the context of lighting and sensing application. It would be interesting to see if such a system can be used as dyes for tunable dye laser applications. Given the vast number of excellent natural fluorescent dyes obtainable from renewable biosources, approaches similar to the present could lead to a more extensive range of low-cost and efficient
Link: WLE biomaterials with ease of adjusting color temperature, which will obviate more expensive alternatives currently being pursued.
Problem Scale: Around the World
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