For the first time, we report on methods to control and prevent polymer films from buckling. Buckled morphologies were created by thermally cycling or mechanically compressing a poly(dimethylsiloxane) substrate coated with a polyelectrolyte multilayer film. By variation of the dimensions of the surface topography relative to the buckling wavelength (e.g., pattern size is less than, equal to, an...

Abstract The thermal resistance of semiconductor thin films is predicted using lattice dynamics (LD) calculations and molecular dynamics (MD) simulations. We consider Si and Ge films with thicknesses, LF , between 0.2 nm and 30 nm that are confined between larger extents of the other species (i.e., Ge/Si/Ge and Si/Ge/Si structures). The LD predictions are made in the classical limit for compari...

Suppression of the glass transition by some tens of degrees within a few tens of nanometers of a free surface in a polymer film is a technologically important, commonly observed, as-yet poorly understood phenomenon. We construct a quantitative theory of the influence of the free surface via transmission of “kinks” or “free volume” along the backbone of loops starting and ending at the free surf...

A thin liquid film subject to a temperature gradient undergoes thermocapillary convection because of the non-uniform surface tension at the free surface. This induced flow perturbs the film free surface and generate a free surface velocity field. These observable consequences can be thought of as the “signature” of the imposed temperature field and this work investigates whether the temperature...

The recent development in oil and gas industry increases the production and consumption of oil. The enormous amount of oily wastewater produced is urged to be treated to prevent humanity and environment from being threatened. Membrane technology is an appealing alternative for oily wastewater treatment due to its design simplicity, energy efficiency and environmentally benign approach. In this ...

Catalyst-free growth of a nanocrystalline few-layer graphene (or graphite) film from photoresist on variable substrates was demonstrated. The thickness of the film can be easily controlled from 1 nm to hundreds of nanometers. With this method, graphene/graphite patterns with different thicknesses have been designed for integrated electronics.

The development of thin film-based structures/devices often requires thin films to be transferred onto arbitrary substrates/surfaces. Controllable and non-destructive transfer method, although highly desired, remains quite challenging. Here we report a general method for fabrication and transfer of hybrid (ultra)thin films. The proposed solution-based in-situ transfer method shows not only its ...

The film thickness of free-meniscus coating of a polymeric fiber with a non-wetting fluid was investigated. A polypropylene monofilament fiber was coated with various glycerol/water mixtures. With a small capillary number (Ca), a detectable liquid film did not form on the fiber due to the non-wettability of the fiber-liquid system. Above a certain threshold velocity, liquid was forced to wet th...

We fabricate mixed halide perovskite films through dual-source vacuum deposition of PbX2 (X = Cl, Br, and I) and methyl ammonium iodide (MAI) precursors with various deposition ratios. Vacuum deposition is an optimal way for film fabrication because it gives a uniform perovskite film which is free from contamination such as metallic phase lead, residual solvent, and moisture. The ionization pot...