Synthesis and tuning orange to green up-conversion color in Y6WO12:Er/Yb phosphor

•Yb3+, Er3+ co-doped Y6WO12 phosphors are prepared by the co-precipitation method successfully.•The phosphors presented uniform spheres at a wide range of annealing temperature.•The luminescent colors of the samples could be modulated by changing the annealing temperatures.•The colors tunable of this phosphor make it an attractive material.•The relative mechanism was given and analyzed.

Spherical Yb3+, Er3+ co-doped Y6WO12 upconversion luminescence (UC) phosphors are prepared by the co-precipitation method. It is found that the phosphors presented uniform spheres at a wide range of annealing the precursors from 600 °C to 900 °C. With increasing the temperature, the particle size has no significant change, but the surface changed from smooth to rough. Further, under 980 nm near infrared (NIR) excitation, the upconversion intensity enhanced with increasing heating temperature, attributing to the more Er3+ incorporated into the Y6WO12 host. Notably, the luminescent colors of the samples could be modulated by changing the annealing temperatures. On the process of increasing heat-treatment temperature from 600 °C to 900 °C, the upconversion emission was tunable from orange to green, which provides a new channel to achieve materials emitting different colors. At last, the possible mechanisms involved were discussed.