Tuning the upconversion light emission by bandgap engineering in bismuth oxide-based upconverting nanoparticles

In the field of novel applications involving upconverting processes, the determination of new strategies for realizing emission-tunable nanomaterials is a challenge. In this work the design of Y3+ and Er3+ codoped bismuth oxide-based upconverting nanoparticles is presented, evidencing how the active role of the matrix allows for the emission selectivity with chromaticity control. The bandgap of the bismuth oxide-based host can be manipulate in a range of 0.65 eV, consequently leading to an upconversion color emission tunability from red to yellow-greenish. The resulting fine control of the nanoparticle chromaticity through accurate host bandgap engineering determines a novel concept for the development of a new generation of upconverting nanophosphors.