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ZrO2 nanotube carrier was obtained using a direct anodization method. Then SO42-/ZrO2 nanotube catalyst was developed in the sulfuric acid solution through ultrasonic dipping processing. The morphology, thermal stability and crystal forms of catalysts were analyzed, and the influence factors of catalytic activity were studied. The results presented in this work show that the catalyst activity was highest under the following conditions: the mass fraction of sulfuric acid solution was 50 %, the ultrasonic dipping time was 20 min, the suitable calcination temperature was 400 °C and the calcination time was 60 min.

Yb/Ho co-doped yttria transparent ceramics, Yb/Ho:Y 2 O 3 , were prepared by vacuum sintering with additional 0.5 wt.% tetraethyl orthosilicate (TEOS) as sintering aid from the Yb/Ho co-doped yttria nanopowders synthesized by co-precipitation method. The optical quality of transparent ceramics was improved significantly, as increasing the sintering temperature from 1800 °C to 1850 °C as well as the holding time from 20 h to 25 h, respectively. The absorption spectrum was measured to find out the advisable emission source wavelength. The 2 μm emission bands were observed under laser diode excitation at 980 nm in the co-doped sample with 5 mol% of Yb 3+ and 1 mol% of Ho 3+ , and broad emission bandwidth were obtained.