Crafting Spin-State Switchable Strain Profiles within Rb x Co[Fe(CN) 6 ] y @K j Ni[Cr(CN) 6 ] k Heterostructures
Crafting Spin-State Switchable Strain Profiles within Rb x Co[Fe(CN) 6 ] y @K j Ni[Cr(CN) 6 ] k Heterostructures
复制标题
在 Rb x Co[Fe(CN) 6 ] y @K j Ni[Cr(CN) 6 ] k 异质结构内制作自旋态可切换应变分布
DOI：
10.1021/acs.chemmater.0c03608
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发表时间：
2021
影响因子：
8.6
通讯作者：
Talham, Daniel R.
中科院分区：
文献类型：
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作者：
Cain, John M.;Felts, Ashley C.;Meisel, Mark W.;Talham, Daniel R.
自旋转变异质结构已经显示出在纳米尺度上诱导大的可切换应力的前景，其体积工作密度类似于压电体，但是在实际应用可行之前，异质结构界面和几何形状如何影响应力的传输，以及反过来，它们如何影响自旋转变致动器本身，必须更好地理解。在这里，四个系列的立方自旋转变普鲁士蓝类似物（PBA）的核壳异质结的开发，以探测的标度行为的应变引起的壳的自旋转变的核心。采用100-600 nm的立方RbxCo[Fe（CN）6]y·nH 2 O（RbCoFe-PBA）颗粒制备了不同系列的RbxCo[Fe（CN）6]y·nH2O@KjNi[Cr（CN）6]k·mH 2 O（RbCoFe@KNiCr-PBA）核壳颗粒，其磁性壳层为15 ~ 130 nm。一个模型适合应变修改磁化提取的“应变体积”的外壳，并与粉末X射线衍射观察到的结构变化的结果进行比较。发现壳的应变体积与核的体积之间存在线性关系，对于较厚的壳，其中磁性KNiCr-PBA壳响应于RbCoFe-PBA核的自旋转变而被影响到大于100 nm的深度。对于薄壳，这种关系更为复杂，因为致动核的体积变化和它在壳中引起的应变变得相互依赖，并且是壳厚度的函数。
Spin-transition heterostructures have shown promise for inducing large switchable stresses at the nanoscale with a volumetric work density similar to piezoelectrics, but before practical applications are feasible, how heterostructure interfaces and geometry influence the transmission of stress and, in return, how they affect the spin-transition actuator itself, must be better understood. Here, four series of cubic spin-transition Prussian blue analogue (PBA) core–shell heterostructures were developed in order to probe the scaling behavior of the strain induced in the shell by the spin transition of the core. Cubic RbxCo[Fe(CN)6]y·nH2O (RbCoFe-PBA) particles ranging 100–600 nm were used to prepare separate series of RbxCo[Fe(CN)6]y·nH2O@KjNi[Cr(CN)6]k·mH2O (RbCoFe@KNiCr-PBA) core–shell particles with magnetic KNiCr-PBA shells ranging from 15 to 130 nm. A model fit to the strain-modified magnetization extracts the “strained volume” of the shell, and the results are compared with structural changes observed with powder X-ray diffraction. A linear relationship is found between the strained volume of the shell and the volume of the core for thicker shells, where the magnetic KNiCr-PBA shell is influenced to depths greater than 100 nm in response to the spin transition of the RbCoFe-PBA core. For thin shells, the relationship is more complicated, as the volume change in the actuating core and the strain it induces in the shell become interdependent and a function of shell thickness.