Unveiling the potential of a self-activated BCNO afterglow phosphor for superior visibility in extremely low-light environments.

The development of versatile luminescent materials with afterglow properties is one of the ways to meet the increasing demands for energy saving. Attempts were being made to develop even self-activated afterglow phosphors by introducing defects in the host lattice, but the number of such phosphors known is limited. Herein, a self-activated rare-earth-free blue-emitting boron carbon oxynitride (BCNO) afterglow phosphor is developed by the sol-gel auto-combustion method at low temperatures (∼700 °C). The formation of BCNO phosphor and its crystal structure are confirmed by XRD and supported by FTIR and XPS analysis. The developed BCNO phosphor features rod-like morphology with high-intensity luminescence properties. Optical and luminescence studies provide insight into the visible light-induced afterglow property of this phosphor. Time-resolved photoluminescence studies showcase that the phosphor has an afterglow duration of around 30 minutes with optimal intensity. Thermoluminescence studies revealed the trap depth of the defects responsible for the afterglow properties and provided an insight into the afterglow mechanism of the phosphor. The BCNO phosphor, when applied over the white-based paint on a vitrified tile, can easily be seen in extremely dark conditions. The visible light-induced afterglow property of the BCNO phosphor has rendered it a prominent material in low-light environments.