High-Efficient Eu3+ Red Emission due to Excitation Energy Transfer from Nano-Sized SnO2 Crystals

Abstract

By overcoming less excitation efficiency of rare-earth ions due to small oscillator strength (∼10-6) of f-f transition, Eu3+ ions were intentionally introduced to nano-sized semiconductor of tin oxide (SnO2) in silica (SiO2)matrix via a sol-gel route. As a consequence, the excitation energy was significantly absorbed by the nano-sized SnO2 with controlled band-gap energy owing to quantum size effect (QSE) and subsequently transferred from nano-sized SnO2 to the Eu3+ ions doped, resulting in the enhancement of Eu3+ red emission (external quantum efficiency : 75.6 %).