Abstract: Ho3 +/Yb3 + co-doped yttria-stabilized zirconia ( 8YSZ ) nano powders were prepared by chemical coprecipitation .The effect of calcination temperatures on the fluorescence spectra and up-conversion luminescence properties of the Ho 3+/Yb3+co-doped nano 8YSZ was investigated .The results show that the Ho 3+/Yb3 +co-doped 8YSZ nano powders have a green emission peak at 549 nm under excitation of the 448 nm wavelength excitation light .The luorescence intensity of the Ho 3+/Yb3+ co-doped 8 YSZ nanopowders increases first , and then decreases with increasing the calcination temperatures.Under excitation of the 980 nm wavelength laser , the Ho3+/Yb3+ co-doped 8YSZ nanopowders have a green emission peak at a central wavelength of 539 nm and a red emission peak at a central wavelength of 650 nm in the range of 450-750 nm.With increasing the calcination temperatures , the particle sizes of the nano powders increase and the upper conversion luminescence intensity also gradually increases .

Key words: Ho3 +/Yb3 + co-doped yttria-stabilized zirconia ( 8YSZ ) nano powders were prepared by chemical coprecipitation .The effect of calcination temperatures on the fluorescence spectra and up-conversion luminescence properties of the Ho 3+/Yb3+co-doped nano 8YSZ was investigated .The results show that the Ho 3+/Yb3 +co-doped 8YSZ nano powders have a green emission peak at 549 nm under excitation of the 448 nm wavelength excitation light .The luorescence intensity of the Ho 3+/Yb3+ co-doped 8 YSZ nanopowders increases first , and then decreases with increasing the calcination temperatures.Under excitation of the 980 nm wavelength laser , the Ho3+/Yb3+ co-doped 8YSZ nanopowders have a green emission peak at a central wavelength of 539 nm and a red emission peak at a central wavelength of 650 nm in the range of 450-750 nm.With increasing the calcination temperatures , the particle sizes of the nano powders increase and the upper conversion luminescence intensity also gradually increases .