Abstract Monodispersed nanoparticles consisting of barium titanate (BaTiO3, BT) as the core and polyvinylpyrrolidone (PVP) as the shell were synthesized in a PVP-assisted low-temperature process in an aqueous solution at ambient pressure. In order to clarify the mechanism of this unique BT–PVP nanoparticle growth and the origin of the dispersion, the concentration and molecular weight of PVP used in the synthesis were varied, and the size and dispersion of the resulting nanoparticles in water were investigated by field-emission scanning electron microscopy and dynamic light scattering. Monodispersed nanoparticles with an average size of 130 nm were obtained by using an intermediate PVP concentration of 100 g/L and a PVP molecular weight of 10,000 g/mol. The thickness of the PVP shell was estimated by thermogravimetric analysis. For the highly dispersed BT–PVP, the thickness of PVP adsorbed on the BT surface was around 3–5 nm. Direct SEM observation of monodispersed BT–PVP in an aqueous solution using a unique sample holder was also demonstrated for the first time.

中文翻译：

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PVP对合成高分散核壳钛酸钡聚乙烯吡咯烷酮纳米粒子的影响

摘要 以钛酸钡(BaTiO3, BT)为核、聚乙烯吡咯烷酮(PVP)为壳的单分散纳米粒子在常压水溶液中采用PVP辅助低温工艺合成。为了阐明这种独特的 BT-PVP 纳米粒子生长的机制和分散的来源，合成中使用的 PVP 的浓度和分子量是不同的，并且通过实地考察了所得纳米粒子在水中的大小和分散情况。 -发射扫描电子显微镜和动态光散射。通过使用 100 g/L 的中间 PVP 浓度和 10,000 g/mol 的 PVP 分子量获得平均尺寸为 130 nm 的单分散纳米粒子。PVP 壳的厚度通过热重分析估计。对于高度分散的 BT-PVP，吸附在 BT 表面的 PVP 厚度约为 3-5 nm。还首次展示了使用独特的样品架对水溶液中的单分散 BT-PVP 进行直接 SEM 观察。