以分析纯氯氧化锆、钨酸铵、氨水和浓硝酸为原材料,采用溶胶-凝胶法合成前驱体,通过后热处理生成α-ZrW2O8.所合成的前驱体为无定形,其在650℃晶型转变完全,但是其转变产物不是ZrW2O8,而是单斜的WO3和ZrO2以及WO3·0.5H2O和W2O6(H2O).温度和时间参数对所合成的前驱体转变过程影响较大.实验结果表明:低于600℃的热处理温度前驱体无法转变成ZrW2O8粉末.前驱体在600℃保温10～18h,随着保温时间的延长,其转变成ZrW2O8的量也相应增加.但在600℃保温时间超过18h,或者热处理温度高于600℃,都使生成的ZrW2O8粉末发生分解.溶胶-凝胶法合成的ZrW2O8粉末颗粒经SEM分析发现,平均粒径在0.1～0.2μm.
参考文献
| [1] | Tao JZ.;Sleight AW. .The role of rigid unit modes in negative thermal expansion[J].International Journal of Quantum Chemistry,2003(2):442-448. |
| [2] | MARY T A;EVANS J S O;VOGT T et al.Negative thermal expansion from 0.3 to 1050 K in ZrW2O8[J].Science,1996,272:90-92. |
| [3] | Evans JSO;Jorgensen JD;Short S .Compressibility, Phase Transitions, and Oxygen Migration in Zirconium Tungstate, ZrW2O8[J].Science,1997(5296):61-65. |
| [4] | C.A. Perottoni;J.A. H. da Jornada .Pressure-Induced Amorphization and Negative Thermal Expansion in ZrW_2O_8[J].Science,1998(5365):886-889. |
| [5] | 程晓农,张美芬,严学华.负热膨胀化合物材料ZrW2O8的机理与制备技术[J].江苏大学学报(自然科学版),2004(03):243-246. |
| [6] | Yuko MORITO;Shaorong WANG;Yoshikazu OHSHIMA .Preparation of Dense Negative-Thermal-Expansion Oxide by Rapid Quenching of ZrW_2O_8 Melt[J].日本セラミックス协会学术论文志,2002(1282):544-548. |
| [7] | MORITO YUKO;TAKAHASHI KOHJI;WANG Shao-rong et al.Press-free preparation method of dense negative thermal expansion oxide,Zr1-x YxW2 O8-δ (x = 0.00-0.02) ceramic using reactive sintering[J].Journal of the Ceramic Society of Japan,2002,110(09):807-812. |
| [8] | KESSLER V G;PANOV A N;BORISSEVITCH A Y U.Molecular precursor role in the synthesis of ZrM2ⅥO8,MⅥ=Mo,W:Isolation and Properties of Zr3 Mo8O24 (Oi Pr) 12 (iPrOH) 4[J].Journal of Sol-Gel Science and Technology,1998(12):81-85. |
| [9] | U. Kameswari;A. W. Sleight;J. S. O. Evans .Rapid synthesis of ZrW_2O_8 and related phases, and structure refinement of ZrWMoO_8[J].International journal of inorganic materials,2000(4):333-337. |
| [10] | CHANG L L Y;SCROGER M G;PHILLIPS B .Condensed phase relations in the systems ZrO2-WO2-WO3 and HfO2-WO2-WO3[J].Journal of the American Ceramic Society,1967,50:211-215. |
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%