結合xDLVO理論與全原子分子動力學模型模擬聚乙烯吡咯烷酮於銀奈米微粒吸附之研究

Abstract

銀奈米微粒廣泛被運用在催化劑、生物感測器、抗菌纖維上，而為了避免銀奈米微粒聚集回到塊材在合成過程中需加入分散劑，而聚乙烯吡咯烷酮（PVP）因為毒性低與易溶於水與有機溶劑的特行而成為常見的分散劑，分散劑避免銀奈米微粒聚集的能力為重要的議題之一。在本研究中，我們利用全原子分子動力學模擬不同鏈長與數量的PVP吸附在直徑4.5 nm與8 nm的銀奈米微粒，以及在不同晶相的銀奈米表面來代替模擬直徑60 nm的銀奈米微粒，探討PVP的形態與分佈，並代入extended DLVO（xDLVO）理論來探討銀奈米微粒間的作用力，此研究結果預期可提供分散劑與奈米微粒溶液設計之參考。

Silver nanoparticles are widely used in catalysts, bio-detectors and antibacterial fibers. Dispersant is added in synthesis of silver nanoparticles in order to prevent the aggregation. Polyvinylpyrrolidone(PVP), due to its low toxicity and high solubility in water and organic solvents, is one of the common-used dispersants in synthesis of silver nanoparticles. The ability of the dispersant to prevent the aggregation of silver nanoparticles is an important issue. In this work, we manipulate all-atom molecular dynamic simulation to simulate the adsorption of PVP with different length and amount on silver nanoparticles with diameter of 4.5 and 8 nm. We simulate the adsorption of PVP on different crystal phase of silver planes in replace of silver nanoparticles with diameter of 60 nm. We research on the shape and distribution of PVP and apply the result to extended DLVO (xDLVO) theory to investigate the force between nanoparticles. The current study is expected to provide guidance for the design of the dispersant and nanoparticles.