Femtosecond Laser Thermal Accumulation-Triggered Micro-/Nanostructures with Patternable and Controllable Wettability Towards Liquid Manipulating

Abstract

Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors, microdroplet self-removal, and liquid–liquid interface reaction applications. However, developing a facile and efficient method to fabricate these versatile surfaces remains an enormous challenge. In this paper, a strategy for the fabrication of liquid manipulating surfaces with patternable and controllable wettability on Polyimide (PI) film based on femtosecond laser thermal accumulation engineering is proposed. Because of its controllable micro-/nanostructures and chemical composition through adjusting the local thermal accumulation, the wettability of PI film can be tuned from superhydrophilicity (~ 3.6°) to superhydrophobicity (~ 151.6°). Furthermore, three diverse surfaces with patternable and heterogeneous wettability were constructed and various applications were successfully realized, including water transport, droplet arrays, and liquid wells. This work may provide a facile strategy for achieving patternable and controllable wettability efficiently and developing multifunctional liquid steering surfaces.

Wettability Controlled Surface for Energy Conversion

“…In this situation, the micro‐protrusions formed by the carbon particles would cause more air pockets between the surface and water droplets, thereby reducing the effective contact area of the surface with water. [ 39 ] The chemical composition of as‐fabricated surfaces was also investigated as displayed in Figure 2f. The overall XPS spectra are shown in Figure S6, Supporting Information.…”

“…In this situation, the micro-protrusions formed by the carbon particles would cause more air pockets between the surface and water droplets, thereby reducing the effective contact area of the surface with water. [39] The chemical composition of as-fabricated of LSHB surfaces produced with triangle (159 ± 3°) and circle (161 ± 2°) arrays. The scale bar is 500 µm.…”

“…Liquid patterning is crucial, both from a fundamental standpoint as well as for various applications such as fog harvesting and microfluidics. [39,42] Figure 4a shows the examples of the well-defined patterned LSHB surfaces. Once the water is introduced, it is completely contained by the watertight superhydrophobic barrier, thus displaying in different shapes (e.g., letters, rings, etc.)…”

Exploitation of the Maximum Entropy Principle in the Study of Thermal Conductivity of Silicon, Germanium and Graphene

“…Phonon transport in GNRs can be modified by changing their dimensions, since width impacts the line-edge-roughness scattering, while an increase in length induces a crossover from ballistic to diffusive heat transport. In GNRs thermal flow can also be adjusted by modifying the isotope concentration, substrate [54], and ribbon crystal orientation. For the energy dispersion relations, we make use of the full ones, which can be obtained by means of the empirical dynamical matrix method consisting of the solution of the below-written eigenvalue problem D(q)u(q) = 0, where u(q) = (u 1 (q), u 2 (q)) T , with T=transposed, u 1 (q), u 2 (q) are the Fourier transforms of the displacement vectors of the two carbon atoms (A and B in Figure 16) contained in the unit cell, and…”

Femtosecond Laser Direct Writing of Optical Overpass

“…et al discussed the effect of various parameters, such as laser fluence, number of pulses, laser beam polarization, wavelength, incident angle, scan velocity, number of scans, and environment, on the formation of different structures. Furthermore, a guideline for surface structure optimization is provided [ 34 , 35 ].…”