采用固相化学反应的方法,成功合成了立方结构的Zr1-xHfxW2O8(x=0,0 3, 0 5, 0 7, 1 0)系列材料.X射线衍射结果表明,Hf4+能替代Zr4+形成二元固溶体,固溶体的晶胞参数与体积随着Hf4+含量x的增加而降低.采用高、低温X射线衍射的方法测定晶胞参数和体积随温度的变化关系,结果表明:Zr1-xHfxW2O8化合物在实验温度范围具有强烈的负热膨胀效应,但其负热膨胀系数不随Hf4+含量x变化.在298～973K,Zr1-xHfxW2O8线膨胀系数α1约为-6×10-6 K-1;在83～298K,Zr 0.5Hf0.5W2O8的α1-9.6×10-6 K-1.变温XRD研究还表明Zr1-xHfxW2O8化合物从α-ZrW2O8相向β-ZrW2O8相的转变温度随Hf4+含量x的增加而略有升高,热重分析(TGA)研究结果表明,Zr1-xHfxW2O8在室温大气条件下不吸水.
参考文献
| [1] | GrahamJ;Wadsley A D;Weymouth J H et al.A new ternary oxide, ZrW2O8[J].Journal of the American Ceramic Society,1959,42(11):570. |
| [2] | Martinek C;Hummel F A .Linear thermal expansion of three tungstates[J].Journal of the American Ceramic Society,1968,51(04):227. |
| [3] | Mary T A;Evans J S O;Vogt T .Negative thermal expansion from 0 3 to 1050 Kelvin in ZrW2O8[J].Science,1996,272(05):90. |
| [4] | Evans JSO;Jorgensen JD;Short S .Compressibility, Phase Transitions, and Oxygen Migration in Zirconium Tungstate, ZrW2O8[J].Science,1997(5296):61-65. |
| [5] | Perottoni C A;Jornada J A H .Pressure induced amorphization an negative thermal expansion in ZrW2O8[J].Science,1998,280(08):886. |
| [6] | Ernst G;Broholm C;Kowach G R et al.Phone density of statesand negative thermal expansion in ZrW2O8[J].Nature,1998,396(12):147. |
| [7] | Ravindran TR.;Mary TA.;Arora AK. .High pressure behavior of ZrW2O8: Gruneisen parameter and thermal properties[J].Physical review letters,2000(17):3879-3882. |
| [8] | Evans J S O;Mary T A;Vogt T et al.Negative thermal expansion in ZrW2O8 and HfW2O8[J].Chemistry of Materials,1996,8:2809. |
| [9] | Evans J S O .Negative thermal expansion materials[J].Journal of the Chemical Society,1999,19:3317. |
| [10] | Yamamura Y.;Tsuji T.;Nakajima N. .Heat capacity anomaly due to the alpha-to-beta structural phase transition in ZrW2O8[J].Solid State Communications,2000(9):453-455. |
| [11] | Hashimoto T.;Morito Y.;Katsube T. .Observation of two kinds of phase transitions of ZrW2O8 by power-compensated differential scanning calorimetry and high-temperature X-ray diffraction[J].Solid State Communications,2000(3):129-132. |
| [12] | Jose Manuel Gallardo-Amores;Ulises Amador;Emilio Moran;Miguel Angel Alario-Franco .XRD study of ZrW_2O_8 versus temperature and pressure[J].International journal of inorganic materials,2000(1):123-129. |
| [13] | Jorgensen JD.;Short S.;Sleight AW.;Evans JSO.;Hu Z. .Pressure-induced cubic-to-orthorhombic phase transformation in the negative thermal expansion material HfW2O8[J].Journal of Applied Physics,2001(6):3184-3188. |
| [14] | CHEN B;Muthu D V S;Liu Z X et al.High pressure Raman and infrared study of HfW2O8[J].Physical Review B,2001,64(21):214111. |
| [15] | Dong C .PowderX: Windows 95 based program for powder X ray diffraction data procession[J].Journal of Applied Crystallography,1999,32:838. |
| [16] | 梁敬魁.相图与相结构[M].北京:科学出版社,1993:407. |
| [17] | Duan N;Kameswari U;Sleight A W .Further contraction of ZrW2O8[J].Journal of the American Chemical Society,1999(121):10432. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%