Correlation between band gap, dielectric constant, Young's modulus and melting temperature of GaN nanocrystals and their size and shape dependences.
Correlation between band gap, dielectric constant, Young's modulus and melting temperature of GaN nanocrystals and their size and shape dependences.
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DOI：
10.1038/srep16939
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发表时间：
2015-11-19
影响因子：
4.6
通讯作者：
Meng X
中科院分区：
文献类型：
--
作者：
Lu H;Meng X
随着结构微型化至纳米级，材料的可检测参数不再保持恒定，而是变得可调。以 GaN 纳米晶体为例，带隙增加，而介电常数、杨氏模量和熔化温度随着固体尺寸的减小而降低。在此，我们基于我们建立的金属纳米晶体内聚能的热力学模型，开发了模型来描述 GaN 纳米晶体这些看似不相关的参数的尺寸和形状依赖性。我们的理论预测与相应的实验或模拟结果之间的一致性证实了所开发模型的准确性，并表明内聚能在描述尺寸和形状对不同低维系统的物理化学性质的影响方面的重要性。
With structural miniaturization down to the nanoscale, the detectable parameters of materials no longer remain constant but become tunable. For GaN nanocrystals example, the band gap increases while the dielectric constant, Young’s modulus and melting temperature decrease with decreasing the solid size. Herein, we developed the models to describe the size and shape dependences of these seemingly uncorrelated parameters for GaN nanocrystals, based on our established thermodynamic model for cohesive energy of metallic nanocrystals. Consistency between our theoretical predictions and the corresponding experimental or simulated results confirms the accuracy of the developed models and indicates the essentiality of cohesive energy in describing the effects of size and shape on the physicochemical properties of different low-dimensional systems.