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The laser-interference-induced backward transfer (LIIBT) that occurred during the nanostripe structuring of materials, performed by two-beam laser interference at the ITO glass/silicon wafer system under a normal atmospheric environment. The results showed that the nanostripe structures with nanoparticles (NPs) can be obtained at the laser fluence of 65–95 mJ·cm−2 for the laser duration of 100 and 200 pulses, respectively. The EDX analysis revealed that the silicon element was transferred on the surface of the nanostripe structures. In addition, Raman spectra with the peaks at ~520 cm−1 verified that the crystalline silicon was deposited on the nanostripe structures during the LIIBT process. Furthermore, the photoluminescence (PL) spectrum with the peak at ~395 nm belongs to the In2O3 nanostructure at the laser fluence of 45 mJ·cm−2 for 200 pulses. The peak at ~405 nm corresponds to the silicon nanostructures and it is covered by SiO at the laser fluence of 75 mJ·cm−2 for 200 pulses. The LIIBT shown here would greatly reduce the complexity in the fabrication of the nanostripe structures and give an impetus to the laser-induced backward transfer.

Despite the success of previous methods for fabricating underwater superoleophobic surfaces, most of the surfaces based on soft materials are prone to collapse and deformation due to their mechanically fragile nature, and they fail to perform their designed functions after the surface materials are damaged in water. In this work, the nanosecond laser-induced oxide coatings on hydrophilic bulk metals are reported which overcomes the limitation and shows the robust underwater superoleophobicity to a mechanical challenge encountered by surfaces deployed in water environment. The results show that the surface materials have the advantage that the underwater superoleophobicity is still preserved after the surfaces are scratched by knife or sandpaper and even completely destroyed because of the hydrophilic property of damaged materials in water. It is important that the results provide a guide for the design of durable underwater superoleophobic surfaces, and the development of superoleophobic materials in many potential applications such as the oil-repellent and the oil/water separation. Additionally, the nanosecond laser technology is simple, cost-effective and suitable for the large-area and mass fabrication of mechanically durable underwater superoleophobic metal materials.

Laser induced forward transfer technology has been reported to print various patterns of 2D and 3D structures in microfabrication for its fascinating characteristics such as non-contact and simple fabrication process. However, the efficiency and throughput are the drawback especially for manufacture of periodical polymer micro-stripes. Here, we proposed a laser interference induced forward transfer (LIIFT) technique, which could produce periodical polymer micro-stripes with high efficiency. The experiment results showed that the good micro-stripe of the polyimide (PI) had been transferred from the PI film, in which the thickness of the PI film, the laser fluence and the pulse number were ~1.2 µm, 39 mJ·cm−2 and 50, respectively. In addition, the relationship of the micro-stripes was systematically analyzed with the laser fluence, the pulse number and the thickness of donor film, respectively. Furthermore, the Fourier transform infrared(FT-IR)spectra showed that these characteristic valleys of the micro-stripe were coincident with those of the PI film, indicating that the micro-stripes transferred were not changed for their composition during the laser processing. Finally, the transferring process was discussed to analyze the formation of the transferred micro-stripes.

Herein, we report for the first time the use of ethanol for the switchable underwater wettability on a rough titanium dioxide (TiO2) surface. The rough TiO2 thin films on the titanium surfaces are fabricated by the high speed wire electrical discharge machining (HS-WEDM) processes, and the resultant surfaces show the switch between underwater superhydrophobicity and oleophobicity via ethanol immersion and dark storage. The underlying mechanism of the switch is depicted, and the result shows that during the ethanol immersion and dark storage, the change of hydroxyl groups leads to the switch. Considering that the use of ethanol is time-saving and low-cost, we anticipate that the use of ethanol will open up a new way of surface wettability change.

Nature gives us a large number of inspirations in designing functional materials. Many plant leaves with self-cleaning properties are ubiquitous in nature. These plants have hierarchical structures, which have extreme repellency to liquids and have considerable technical potential in various applications. Herein, we present a method for fabricating bionic taro leaf surfaces by direct laser interference lithography (DLIL) and hydrothermal treatment. The micro-pillar array structure (MPA) was fabricated by DLIL, and a layer of nano-grass structure (NG) was grown on it by hydrothermal treatment. Experiments indicate that the hierarchical composite structures not only have a satisfactory superhydrophobic function with the apparent contact angle (CA) of 172° and sliding angle (SA) of 4°, but also have a strong anti-icing ability with the delay time (DT) of 3723 s. The method is simple and high-efficient for fabricating bionic self-cleaning and anti-icing surfaces.

The crossing porous structure of InP has been obtained by electrochemical etching in NaF solutions. The behavior of the periodic oscillation occurs at different potential ranges for the different concentrations of solutions, and it will disappear with the concentration of the solution decreased. The scanning electron microscope (SEM) image shows that the pores have two directions on the surface and are perpendicular to each other. The two directions are assigned to [0 1 1] and [ 0 1 ¯ 1 ], respectively. The SEM image of the cross-section also shows that the two directions are assigned to [1 1 1]B and [ 1 1 ¯ 1 ¯ ]B. Both are due to the selective etching of F− ions. The crossing porous structure of InP is a very promising feature for the three-dimensional structure of III–V compound semiconductors for photonic band gap materials.

In this work, cathodic electrochemical deposition was proposed to fabricate reproducible and homogeneous hematite (α-Fe2O3) nanoparticles on indium-tin-oxide (ITO) films. The α-Fe2O3 nanoparticles, which were quasi-hexagonally shaped, were deposited in an aqueous mixture of FeCl2 and FeCl3 at the temperatures 16.5 °C, 40 °C and 60 °C. The electrochemically deposited α-Fe2O3 nanoparticles showed excellent stability and good crystallinity. The α-Fe2O3 nanoparticles were characterized by Raman spectroscope and X-ray diffractometer (XRD). A scanning electron microscope (SEM) was used to measure the size and shape of the nanoparticles. The experiment results have shown that the size and shape of nanoparticles were determined by electrochemical deposition conditions including the deposition time, current density, reaction temperature and solution concentration. The proposed electrochemical deposition method has been proven to be a cost-effective, environment friendly and highly efficient approach in fabricating well decentralized α-Fe2O3 nanoparticles for different potential applications.