Energy Transfer Mechanisms in Tb3+ Doped Perovskite Quantum Dots Germanium Borate Glass Ceramics with Enhanced Luminescence Efficiency

Abstract

In recent years, rare earth ions doping has enhanced the luminescence performance of perovskite quantum dots (PQDs) glass, but the enhancement mechanism caused by internal energy transfer deserves further study. In this work, a series of CsPbBr3 PQDs doped with different concentrations of Tb3+ ions was prepared in germanium borate glass matrix by traditional melt quenching method and heat treatment process. The experimental results indicate that after introducing Tb3+ ions into the PQDs glass, the photoluminescence intensity has been significantly enhanced, and the photoluminescence quantum yield increased from 14.8% to 46.1%. The occurrence of this phenomenon can be attributed not only to the role of Tb3+ as a nucleating agent in PQDs glass which facilitates the formation of more small-sized CsPbBr3 but also replaces Pb2+, thereby alleviating lattice distortion and passivating defects. Moreover, the core mechanism lies in the energy transfer process between Tb3+ and CsPbBr3. It has been verified that there not only has a radiative photon reabsorption process that Tb3+ can releases photons for CsPbBr3 to absorb but also has a Förster resonance energy transfer process that Tb3+ directly transfers energy to CsPbBr3 in a non-radiative form. Finally, considering the differing thermal attenuation rates of Tb3+ and CsPbBr3 in glass, a temperature-dependent luminescence color-tuning strategy is proposed, which has potential application value in the field of temperature sensing.