We describe a facile and novel method for preparing highly dense Langmuir–Blodgett (LB) nanofilms of poly(vinylidene fluoride) (PVDF) with precisely adjustable film thickness from several to hundreds of nanometers, assisted by amphiphilic poly(N-dodecylacrylamide) (pDDA) nanosheets. Even at a molar mixing ratio of PVDF:pDDA up to 50:1, the high collapse surface pressure of 44.4 mN/m obtained using this method is a breakthrough for the preparation of PVDF LB nanofilms, which is devoted to the resulting high-density PVDF nanofilms. As shown by FTIR and XRD measurements, the mixed LB nanofilms without any postprocessing comprised dominant ferroelectric β phase of ∼95% and negligible paraelectric α phase. Furthermore, through control of the surface pressure, controllable PVDF crystal morphologies were achieved. Moreover, β phase PVDF dominates in all cases. After applying a dc bias of 5 V through a conductive cantilever, the local polarized pattern on the surface of a nine-layer mixed LB nanofilm observed using Kelvin probe force microscopy indicates that it is possible to induce all dipoles in one direction in the mixed LB nanofilm, which is promising for application in low-voltage nanoelectronics.

As-deposited PVDF LB nanofilms with a complete β phase show a remarkable remanent polarization and long fatigue endurance greater than 105cycles.

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Room temperature magnetoresistance devices using ferroelectric poly(vinylidene fluoride) as the spacer layer were successfully fabricated for the first time.

Boronic acid-containing polycyclosiloxane showed unique self-assembly nanofilm formation (6 nm film thickness) on various substrates and provided film-based metal ion sensor capability through dynamic covalent bonding.

Fluorinated cellulose nanofiber assemblies exhibit high oil–water separation efficiency and recyclability (at least 50 times) for practical applications.

Fabrication of poly(vinylidene fluoride) copolymer monolayer (3.5 nm thick) was succeeded, exhibiting superior ferroelectricity and potential applications as non-volatile memories.

The present work addresses the solvent-dependent properties of Langmuir films of poly(vinylidene fluoride) (PVDF) and amphiphilic poly(N-dodecylacrylamide) (pDDA) at different mixing ratios. After introducing pDDA nanosheets, PVDF Langmuir films obtain a tremendously enhanced modulus as well as high transfer ratios using the vertical dipping method caused by the support of the pDDA two-dimensional hydrogen bonding network. Brewster angle microscopy (BAM) was used to investigate PVDF monolayers at the air-water interface in situ. Spreading from different solvents, the PVDF molecules take completely different aggregation states at the air-water interface. The PVDF molecules aggregate to become large domains when spread from N-methyl-2-pyrrolidone (NMP). However, the volatile and low-polarity methylethyl ketone (MEK) made the PVDF molecules more dispersive on the water surface. This study also discovers a versatile crystallization control of PVDF homopolymer from complete β phase (NMP) to complete α phase (MEK) at the air-water interface, thereby eliciting useful information for further manipulation of film morphologies and film applications.