Structure and photoluminescence of α-MoO3:Eu3+ microbelts

Phosphors of alpha-MoO3 with varying concentrations of Eu activator emitting an orange-red color were synthesized using a conventional solid-state reaction. The sintered pellets consisted of microbelts with a wide size distribution. The surface morphology became rough with an increase in the sintering temperature, which was attributed to a higher proportion of large and transparent nonluminous microbelts under ultraviolet light. Photoluminescence of 1 at.% Eu-doped alpha-MoO3 pellet sintered at 710 degrees C exhibited the strongest intensity. Ultrasonic vibrations caused the disruption of interlayer bonding and fragmentation in the horizontal direction of the alpha-MoO3 crystals, resulting in smaller belts with a thickness of 10-20 nm. The finely fragmented Eu-doped alpha-MoO3 microbelts dispersed in water retained luminescent properties under ultraviolet light with a wavelength of 254 nm. The report on the fabrication of emitting alpha-MoO3 micro/nanobelts through sintering and subsequent ultrasonication is promising for developing low-cost and large-area optical devices.