α-TeO2: Ho3+ ,Yb3+ ,α-TeO2: Tm3+ ,Yb3+ and α-TeO2: Tm3+ ,Ho3+ ,Yb3+ nanoparticles were prepared via a hydrothermal process. Under 980 nm excitation, α-TeO2- Ho3+ , Yb3+ nanoparticles showed green (545 nm) and red (651 nm) emission, which were attributed to the sS2→ 5I8 and 5F5→ 5I8 transitions, respectively. The up-conversion emission color changed markedly from yellow to green when the mole fraction of Yb3+ ions changed from 5% to 15% due to the green emission at 545 nm increased. The a-TeO2: Tm3+ , Yb3+ sample showed blue emission at 476 nm, which was attributed to the 1G4→3H6 transition, and two weak red (651, 675 nm) emissions, which were attributed to the 1G4→3F4 and 3F2→3H6 transitions, respectively. The relative intensity ratio of the blue emission to the red emissions increased gradually with increasing Yb3+ concentration. Based on the generation of blue, green and red emissions, the α-TeO2: Tm3+ ,Ho3+ ,Yb3+ nanoparticles could compose different color, including white, by controlling the doping concentration of rare earths in the α-TeO2 nanoparticles.u0000ng Yb3+ co%利用简单的水热合成法成功制备出α-TeO2∶Ho3+,Yb3+、α-TeO2∶Tm3+,Yb3+和α-TeO2∶Tm3+,Ho3+,Yb3+纳米材料,用980 nm的近红外光作为激发光源测定了样品的室温上转换发射光谱.结果表明:样品α-TeO2∶Ho3+,Yb3+分别发射绿光(545 nm)和红光(651 nm),分别对应于Ho3+离子的5S2→5I8和5F5→5I8能级跃迁.随着Yb3+的摩尔分数从5％增加到15％,样品在545 nm处的绿光强度明显变大,发光颜色由黄光向绿光转变.样品α-TeO2∶Tm3+,Yb3+在476 nm处发射出蓝光,对应于Tm3+离子的1G4→3H6能级跃迁,两个弱红光峰(651,675 nm)分别对应于Tm3+离子的1G4→3F4和3F2→3H6能级跃迁.随着Yb3+离子浓度的提高,蓝光与红光的相对强度也在显著提高.基于可调控性蓝光、绿光和红光的产生,α-TeO2∶Tm3+,Ho3+,Yb3+纳米材料能产生不同颜色的光,包括白光.
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