Bright white light emission from lanthanide oxide LaGdO 3 for LED lighting by Bi 3+ to Eu 3+ energy transfer.

Phosphors with intrinsic white light emission are of great potential in constructing high-quality white LEDs (WLEDs). In this work, we propose the use of energy transfer from Bi 3+ to Eu 3+ ions for white light emission. A unique Bi 3+ -activated phosphor LaGdO 3 (LGO):Bi 3+ was generated using the conventional high-temperature solid-state process. An energy transfer was established by introducing Eu 3+ into the phosphor composition. The emission colour of LGO:Bi 3+ ,Eu 3+ phosphors changes from cyan to white to orange-red depending on the Bi 3+ /Eu 3+ doping proportion. The energy transfer between the Bi 3+ and Eu 3+ ions results from the dipole-dipole interaction. The LGO:Bi 3+ ,Eu 3+ phosphors were combined with a near-ultraviolet chip to successfully create a single-component WLED device with a colour-rendering index of 92.4. Our work demonstrates the energy transfer as a route for single-component white light emission and makes LGO:Bi 3+ ,Eu 3+ phosphors one of the candidate materials for near-ultraviolet lighting.