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Correction for ‘A robust and flexible bulk superhydrophobic material from silicone rubber/silica gel prepared by thiol–ene photopolymerization’ by Yongsheng Li et al., J. Mater. Chem. A, 2019, DOI: 10.1039/c8ta11111a.

Al2O3-Pt/YSZ-Pt double layer composite coatings were prepared by cathode plasma electrolytic deposition (CPED) on the superalloy with a NiCoCrAlY bond-coat. The composite coatings consist of an Al2O3-Pt film and a YSZ-Pt top-coat and show a good adhesion to the metallic bond-coat. It is demonstrated, from the cyclic oxidation test and mechanical properties test, that such coatings possess good oxidation and spallation resistance. These beneficial results can be attributed to these effects: owing to the extremely low oxygen diffusion rate of Al2O3-Pt film, such composite coatings can inhibit further oxidation of the bond-coat; the mechanical properties of Al2O3-Pt/YSZ-Pt composite coating are improved by the toughening effect of Pt particles.

Considering the difficulties of the low signal-to-noise ratio in weak radioactive source detections, this study proposes an abandon Gaussian tails method based on the analysis of the characteristic information denoted by the full-energy peak of the gamma spectrum of a gamma-emitting radioactive source. Based on the study of the signal-to-background ratio and the statistical fluctuations in the signal of the weak radioactive source, a factor ζ, incorporating the statistical fluctuations of signal and background and the signal-to-background ratio, is suggested to characterize the sensitivity of a radioactive source detection. When ζ reaches its maximum value, the optimal counting window around the centroid of the full-energy peak can be obtained. To evaluate the effectiveness of the proposed approach, comparisons between the proposed abandon Gaussian tails, the conventional full-energy counting, and other experiential methods were performed. The results show that the sensitivity can be significantly improved. Further, experiments with different intensity of radiation sources and duplicated experiments were conducted to examine the stability of the proposed method.

Building a superhydrophobic coating on polymer films is an important way to obtain water-proof surfaces. However, due to the poor mechanical strength and weak adhesion between coating and substrate, the superhydrophobicity of the coating is easily lost under mechanical loads. In this study, a facile approach was proposed to build a mechanically stable superhydrophobic poly(chloro-p-xylylene) (PPXC) film by pre-coating a polydimethylsiloxane adhesive layer (PDMS AL) on the original PPXC film and coating a superhydrophobic PDMS and silica (PDMS/SiO2) layer on the PDMS AL layer. As demonstrated by Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) measurements, the thermal cross-linking reaction between the PDMS/SiO2 coating and the PDMS AL layer could dramatically promote the interaction between the PDMS/SiO2 coating and the PPXC film. By tuning pre-curing time and the content of PDMS AL, the mechanical stability of the PDMS/SiO2 coating on PPXC film could be adjusted. Under the optimal conditions of pre-curing time and the content of PDMS AL, the PPXC film showed robust superhydrophobicity and self-cleaning ability against various mechanical damages, such as 3M tape peeling and cyclic abrasion. The superhydrophobic coating on PPXC film with PDMS AL showed a higher peeling resistance than that on PPXC film without PDMS AL. Moreover, the superhydrophobic coating on PPXC film with PDMS AL maintained its original superhydrophobicity even after 4000 cycles of abrasion.

To fabricate mechanically stable superhydrophobic surfaces, conventional methods often involve complicated and time-consuming processing to improve the interface adhesion between coating and substrate, such as multi-step pre-treatments of the substrate and long time post-curing for both substrate and coating. Here, we report a facile and fast method to prepare the robust and stretchable superhydrophobic surface by rapid UV cross-linking of the superhydrophobic coating (based on polydimethylsiloxane/silica composite) onto a stretchable substrate. Polyurethane acrylate (PUA) with double bonds was UV cured to form the stretchable elastomeric substrate, the surface of which remains uncured PUA due to the presence of oxygen inhibition. The oxygen-inhibited layer of the substrate can provide a lot of reactive sites for covalently bonding to the superhydrophobic coating under UV exposure and thus eliminates the requirement for complicated surface treatments of the substrate. The formed covalent cross-linking between the superhydrophobic coating and the PUA substrate facilitates their interface adhesion. As expected, the superhydrophobic coating covalently-bonded to the PUA substrate shows good superhydrophobicity and self-cleaning ability against mechanical abrasion and stretching damages. Besides, the resulting superhydrophobic surface can withstand 1000-cycle stretching-releasing (strain of 0% → 200% → 0%) without losing its original superhydrophobicity. Thus, this robust superhydrophobic surface could find a wide range of water-proof applications for flexible substrates such as stretchable electronics, functional textiles, and outdoor sport goods.

For photon detection, superconducting transition-edge sensor (TES) micro-calorimeters are excellent energy-resolving devices. In this study, we report our recent work in developing Ti-/Au-based TES. The Ti/Au TES devices were designed and implemented with a thickness ratio of 1:1 and different suspended structures using micromachining technology. The characteristics were evaluated and analyzed, including surface morphology, 3D deformation of suspended Ti/Au TES device structure, I–V characteristics, and low-temperature superconductivity. The results showed that the surface of Ti/Au has good homogeneity and the surface roughness of Ti/Au is significantly increased compared with the substrate. The structure of Ti/Au bilayer film significantly affects the deformation of suspended devices, but the deformation does not affect the I–V characteristics of the devices. For devices with the Ti/Au bilayer (150 – m × 150 μm) and beams (100 μ m × 25 μm), the transition temperature (T c) is 253 mK with a width of 6 mK, and the value of the temperature sensitivity α is 95.1.

Enhancing surface wetting is very critical for various applications of polymer films. Although existing modification methods (e.g., UV radiation and plasma treatments) can improve the wetting of polymer films by inserting hydrophilic groups, the resultant polymer surface is unstable and shows strong hydrophobic recovery in a short time (less than 1 day) due to the rearrangement of the polymer chains. Herein, we report a new approach to prepare stable wetting surface by cross-linking hydrophilic poly(acrylic acid) (PAA) molecules on poly(chloro-p-xylylene) (PPXC) films via hyperthermal hydrogen induced cross-linking (HHIC) treatment. With the HHIC treatment, the polar functionalities of PAA (e.g., −COOH) can be preserved through selective cleavage of C–H bonds and subsequent cross-linking of resulting carbon radicals generated on PAA and PPXC chains. HHIC-treated PAA–PPXC film shows an excellent wetting stability, of which WCA and surface energy stay almost the same over 40 days. The improved wetting stabi...

Poly(chloro-p-xylylene) (PPXC) film has a water contact angle (WCA) of only about 84°. It is necessary to improve its hydrophobicity to prevent liquid water droplets from corroding or electrically shorting metallic circuits of semiconductor devices, sensors, microelectronics, and so on. Herein, we reported a facile approach to improve its surface hydrophobicity by varying surface pattern structures under different temperature and relative humidity (RH) conditions on a thermal curable polydimethylsiloxane (PDMS) and hydrophobic silica (SiO2) nanoparticle coating. Three distinct large-scale surface patterns were obtained mainly depending on the contents of SiO2 nanoparticles. The regularity of patterns was mainly controlled by the temperature and RH conditions. By changing the pattern structures, the surface wettability of PPXC film could be improved and its WCA was increased from 84° to 168°, displaying a superhydrophobic state. Meanwhile, it could be observed that water droplets on PPXC film with superhydrophobicity were transited from a “Wenzel” state to a “Cassie” state. The PPXC film with different surface patterns of 200 μm × 200 μm and the improved surface hydrophobicity showed wide application potentials in self-cleaning, electronic engineering, micro-contact printing, cell biology, and tissue engineering.