聚乙烯吡咯烷酮对亚微米级铜晶体的形貌控制机制

Morphology Control Mechanism of Polyvinylpyrrolidone on Submicron Copper Crystals

摘要:

利用聚乙烯吡咯烷酮(PVP)调控亚微米级铜晶体的形貌,借助SEM、XRD及激光粒度分析仪对铜晶体微观性能进行了表征,采用Materials Studio软件结合Gibbs-Wulff定律(晶体生长平衡理论)推测PVP分子在Cu各晶面的吸附行为及铜晶体的形貌变化规律,研究结果表明：经PVP改性后,铜晶体由截角八面体转变为近球形。PVP在铜各晶面主要发生化学吸附,吸附强弱顺序为：(111)>(200)>(220)。PVP对亚微米级铜晶体的形貌控制机制在于PVP与Cu形成具有共价性的不稳定配合物,抑制了(111)、(200)和(220)晶面的生长,显露了更多的晶面,导致了Cu晶体更趋近于球形。

Abstract:

The morphology of submicron copper crystals was controlled by polyvinylpyrrolidone (PVP). The microscopic properties of copper crystals were characterized by SEM, XRD and laser particle size analyzer. The Materials Studio was used to combine Gibbs-Wulff"s law (crystal growth balance theory). It is speculated that the adsorption behavior of PVP molecules on the crystal faces of Cu and the morphology of copper crystals show that the copper crystals are transformed from truncated octahedron to nearly spherical after PVP modification. PVP mainly undergoes chemisorption on the crystal faces of copper. The order of adsorption is: (111)>(200)>(220). The morphology control mechanism of PVP on submicron copper crystals is that PVP forms a covalently unstable coordinating chelate with Cu, inhibiting the growth of (111), (200) and (220) crystal planes, revealing more crystal planes result in the Cu crystals becoming closer to a sphere.