摘要
绝大部分物质具有热胀冷缩的基本性质,然而近年来的研究发现一些化合物具有反常的负热膨胀性质,其为有效调节物质热膨胀系数(CTE)提供了可行性,尤其调控各向同性化合物热膨胀性质是一个重要的研究方向。本文以双Re O_3结构的固溶体(Fe_(1-x)Ni_x)Zr F_6为研究对象,对(Fe_(1-x)Ni_x)Zr F_6固溶体的制备、晶体结构以及热膨胀调控开展了深入研究。(Fe_(1-x)Ni_x)Zr F_6固溶体呈现全程固溶特性,通过Ni^(2+)对Fe^(2+)进行化学替代的方法实现了(Fe_(1-x)Ni_x)Zr F_6热膨胀系数在大范围内的有效调控(-3.24×10^(-6)–+18.23×10^(-6) K^(-1),300–675 K),尤其,在(Fe_(0.5)Ni_(0.5))Zr F_6化合物中得到了零膨胀性能。作为一种典型的框架结构化合物,晶胞中F原子横向热振动的差异是导致各自不同热膨胀差异的本质原因。该研究给我们提供了一个基于开放式框架结构化合物的热膨胀调控方法。
Most materials expand on heating and contract on cooling. In the recent years, however, some compounds have been found to exhibit abnormal negative thermal expansion （NTE） behavior; this presents an opportunity to adjust the coefficient of thermal expansion （CTE） of such materials. It is especially important to obtain controllable thermal expansion in isotropic compounds. Herein, we report the preparation, crystal structure, and controllable thermal expansion in double ReO3-type （Fel-xNix）ZrF6 solid solutions. （Fel-xNix）ZrF6 exhibits full range solubility. A controllable thermal expansion of （Fel-xNix）ZrF6 could be achieved by the chemical substitution of Ni2 for Fe2. over a wide range of CTE from -3.24 × 10^-6 to ＋18.23 × 10^-6 K-1 （300-675 K）. In particular, zero thermal expansion was obtained for the composition （Fe0.sNi0.s）ZrFs. As a kind of typical framework structure, the transverse thermal vibrations of fluorine atoms are expected to play a critical role in the thermal expansion behavior of double-ReO3 compounds. This study presents a potential method to tune the thermal expansion of NTE （negative thermal expansion） families which have an open framework structure.
作者
许家乐
胡磊
王璐
邓金侠
陈骏
邢献然
XU Jiale, HU Lei, WANG Lu, DENG Jinxia, CHEN Jun, XlNG Xianran(Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, P. R. China)
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2018年第4期339-343,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(91422301.21231001)和中央高校基础科研业务费专项基金(FRY-TP-14-012C1)资助项目
关键词
固溶体
氟化物
氧化铼
热膨胀调控
零膨胀
Solid solution
Fluorides
ReO3
Controllable thermal expansion
Zero thermal expansion
