Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) receives increasing attention in membrane separation field based on its advantages such as high mechanical strength, thermal and chemical stability. However, controlling the microporous structure is still challenging. In this work, we attempted to tailor the morphology of PVDF-HFP membrane via a one-step reactive vapor induced phase separation method. Namely, PVDF-HFP was dissolved in a volatile solvent and then was cast in an ammonia water vapor atmosphere. After complete evaporation of solvent, membranes with adjustable porous structure were prepared, and the microstructures of the membranes were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction characterizations. Based on the results, a mechanism of dehydrofluorination induced cross-linking of PVDF-HFP has been suggested to understand the morphology tailoring. To our knowledge, this is the first report of one-step reactive vapor induced phase separation strategy to tailor morphology of PVDF-HFP membrane. In addition, the membranes prepared in the ammonia water vapor exhibited enhanced mechanical strength and achieved satisfactory separation efficiency for water-in-oil emulsions, suggesting promising potential.

聚偏二氟乙烯-共六氟丙烯（PVDF-HFP）凭借其高机械强度，热和化学稳定性等优点而在膜分离领域受到越来越多的关注。然而，控制微孔结构仍然具有挑战性。在这项工作中，我们试图裁缝PVDF-HFP膜的形态通过一种单步反应性气相诱导相分离方法。即，将PVDF-HFP溶解在挥发性溶剂中，然后在氨水蒸气气氛中浇铸。溶剂完全蒸发后，制备具有可调多孔结构的膜，并通过扫描电子显微镜，傅里叶变换红外光谱，X射线光电子能谱和X射线衍射表征分析膜的微结构。基于该结果，已经提出了由脱氟化氢诱导的PVDF-HFP交联的机理以理解形态学剪裁。据我们所知，这是一步反应性气相诱导相分离策略的第一份报告，该策略可定制PVDF-HFP膜的形态。此外，