Long Afterglow Room-Temperature Phosphorescence from Nanopebbles: A Urea Pyrolysis Product
Khemnath Patir1, Sonit Kumar Gogoi1
1Department of Chemistry, University of Gauhati, G. B. Nagar, Guwahati-, 781014, Assam, India.
Abstract:
Materials having long afterglow are highly sought after for various applications such as light-emitting diodes, security signs and bioimaging. Herein, we report a simple, low-cost synthesis of a purely organic room-temperature phosphorescent nanomaterial with a pebble-like structure by heating urea, a biocompatible and easily available precursor, at 200 °C with a high phosphorescence lifetime of 1.0365 s and a visible afterglow for up to 10 s. This urea derived phosphorescent nanocomposite (UPNC) can be mixed with commercially available acrylic paint base and common gum, which can be readily used as a phosphorescent pigment.
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