微纳米水合盐相变材料Na_2CO_3·7H_2O的仿生合成及热学性质研究

Biomimetic synthesis and thermal property of Na_2CO_3·7H_2O as phase change materials with micro-and nanostructures

以定量滤纸为生物模板制备了具有定量滤纸形貌的Na2CO3晶体,经过低温下的吸水和结晶过程合成了相变材料Na2CO3·7H2O。并借助扫描电子显微镜(SEM)、X-射线粉末衍射仪(XRD)和差示扫描量热仪(DSC)对产物的形貌、晶型以及热学性质进行了表征。同时,考察了掺杂NaCl对合成的相变材料Na2CO3·7H2O的热学性能的影响。结果表明:产物纯度高,且很好地遗传了模板(滤纸)的形貌;Na2CO3.7H2O表现出了良好的储能效果,相变热可达216.8J/g;掺杂NaCl(20mol%)可使Na2CO3.7H2O的相变温度降低5.5℃,而相变热仍然高达177.9J/g。

The biomorphic NazCOa using filter paper as biotemplate was prepared, and it was transformed into Na2CO3·7H20 during the process both drinking and crystallization under low temperature. The samples were character- ized by scanning electron microscopy （SEM）, powder X-ray diffraction （XRD） and differential scanning calorimetry （DSC）. Meanwhile, the effect of doping of NaC1 on the thermal property Na2 CO3·7H20 was studied. The results showed that products had high purity and faithfully duplicated the morphologies of the biotemplate （filter paper）. The prepared Na2CO3·7H2O showed excellent heat storage property and the heat of phase change was 216. 8J/g. At the same time, doped NaC1 （20mol%） could obviously reduced the temperature of phase change by 5. 4℃ and the heat of phase change still reached 177.9J/g.