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In nature, animals or plants often use soft organs to move and hunt. Research works on bioinspired materials and devices have attracted more and more interest as which show the potential for future intelligent robots. As key components of soft robots, biomimetic soft actuators are adapted to greater requirements for convenient, accurate, and programmable controlling robots. Here, a class of materials and processing routes of ultrathin actuators are reported for bioinspired piecewise controllable soft robots, where the actuators associate with thermal‐responsible soft silicone thin film with thickness as thin as 45 µm and electrically driven by well mechanical designed metallic thin film electrodes. Multiple electrodes in the robots in charge of individual segments control allow the soft robots exhibiting similar functionalities of animals or plants (for example, imitating the tongue of a reptile, such as chameleon to hunt moving preys, and mimicking vines to tightly wind around objects). These bionic results in the soft robots demonstrate their advantages in precise and flexible operation, which provides a good reference for the future research of intelligent soft actuators and robots. [ABSTRACT FROM AUTHOR]

In this work, hydrogenated microcrystalline silicon germanium (µc-Si 1− x Ge x :H) thin films were fabricated by plasma-enhanced chemical vapor deposition (PECVD) and developed as the infrared absorber for thin film silicon solar cells. Three kinds of the non-uniform distribution in µc-Si 1− x Ge x :H thin films including: “the non-uniform distribution of Si and Ge”, the non-uniform distribution of crystallization”, and “the non-uniform distribution of H”, and how these affect the structural, optical and photoelectric properties of µc-Si 1− x Ge x :H thin films have been explored. The results show that the good film quality of µc-Si 1− x Ge x :H is associated with the low crystalline volume fraction and microstructure factor. The band gap of µc-Si 1− x Ge x :H is determined by the proportion of the Ge-related crystalline networks. In addition, it is suggested that the deterioration of the photosensitivity of µc-Si 1− x Ge x :H is mainly due to the increase of the Ge clusters with higher micro-void and defect density. Furthermore, by using µc-Si 1− x Ge x :H bottom sub-cells, the comparable efficiency can be realized under the thin thickness condition. An efficiency of 11.35% in an a-Si:H/a-Si 0.6 Ge 0.4 :H/µc-Si 0.5 Ge 0.5 :H triple junction structure with total cell thickness as thin as 1200 nm was obtained. It is believed that the µc-Si 1− x Ge x :H thin films can be a better candidate for effective infrared absorber by further improving its microstructure uniformity. [ABSTRACT FROM AUTHOR]

Abstract: Novel Cu2O/Pt/TiO2 three-layered nanocomposite films were prepared by deposition on glass substrates using the magnetron sputtering method. Their structure, surface morphology as well as optical and photocatalytic properties were examined by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, UV–visible spectroscopy, and photoluminescence spectroscopy. As a comparison, Cu2O/TiO2 double-layer films were also investigated. The results show that Cu2O/TiO2 double-layer films have relatively smooth surfaces with agglomerated Cu2O particle, whereas the surface layer of the Cu2O/Pt/TiO2 three-layered nanocomposite films was composed of fine nano-sized columnar Cu2O and they had a rough surface morphology due to the insertion of the Pt layer. The photocatalytic activity of the three-layered films is significantly higher than that of the Cu2O/TiO2 double-layered composite films. Such enhancement is closely related to the presence of the Pt layer and the rough surface, which was composed of fine nano-sized Cu2O columns; this increases the utilization of visible light as well as promotes the transfer of interfacial charge and the separation of photogenerated electron–holes. [Copyright &y& Elsevier]

In this work, Cu(In,Ga)Se2 (CIGS) absorbers were deposited on polyimide substrates using the low-temperature three-stage process, and different sodium incorporation methods were applied to investigate the effects of Na on the CIGS growth. It was found that Na affected the CIGS film growth significantly during the second stage of the process, and resulted in a higher Ga content near the back contact. The CIGS thin films with different Na-incorporation methods exhibited similar electrical parameters. A modelling investigation was also implemented by using the wxAMPS software package to quantitatively analyse the effects of different Ga gradient to the device characteristics. Finally, the device performance showed little difference between the post-deposition treatment of NaF and the co-evaporation of NaF during the third stage. [ABSTRACT FROM AUTHOR]

Abstract: This short communication presents a novel approach for testing the interfacial normal bond strength of thin laminated metallic composite plates. The upper limit of the interfacial normal bond strength measured by four-point bending test on butt-joint specimens is about 1.5 times higher than that by uniaxial tension test. [Copyright &y& Elsevier]

Covalent organic framework (COF) membranes show great potential for gas separation, but their large pore size make it hard to effectively separate gases with similar kinetic diameters. A promising strategy is to cover the surface of COF membranes with an ultrathin film of ionic liquids (ILs) to improve the selectivity of gas permeation. Here, we investigated the CO 2 /CH 4 separation performance of composite membranes composed of COF (CTF-1) and 20 kinds of ILs, respectively, using molecular simulations. The [C 4 mim][PF 6 ]/COF membrane is found to exhibit the best separation performance, with CO 2 permeability up to 7.93 × 104 GPU and CO 2 /CH 4 selectivity of 12.33 when the IL thickness is 8 Å. By studying the microstructure of the composite membrane, it was found that there is a relatively dispersed distribution of cations and anions on the COF surface, which is beneficial to the diffusion of gas molecules. The gas permeation process results reveal that CO 2 rapidly achieves equilibrium in both the adsorption and dissolution layers simultaneously, thereby enhancing the permeation rate of gas molecules. The analysis of interaction energy and PMF indicates that the improved selectivity is due to the stronger interaction between IL and CO 2 than that for CH 4. [Display omitted] • 20 types of ultrathin IL-covered COF membranes for separating CO 2 /CH 4 were proposed. • [C 4 mim][PF 6 ]/COF membrane exhibits the highest separation performance. • The dispersed and uniform ionic distribution on the COF surface permits rapid gas diffusion. • The stronger IL-CO 2 interaction compared to CH 4 enhances selectivity. [ABSTRACT FROM AUTHOR]

Abstract: Poly (lactic acid)/anatase-titanium dioxide (PLA/A-TiO2) and PLA/rutile-TiO2 (PLA/R-TiO2) composites were prepared by spin coating technique (thin film) and extrusion-injection processing (thick film), respectively. The ultraviolet (UV) photoresponse effects of the two oxide structures were investigated mainly by measuring the UV absorbance or mechanical properties. For the thin films, the UV absorbance results exhibit a UV shielding effect of R-TiO2 and a degradation acceleration effect of A-TiO2 when the particles are embedded in PLA matrix. But for the thick films, the mechanical property results only exhibit a UV shielding effect of both R-TiO2 and A-TiO2 particles and improve the anti-UV performance of PLA when the particles are encapsulated in PLA matrix. [Copyright &y& Elsevier]

Abstract: In this paper, a new liquid membrane technique, hollow fiber renewal liquid membrane (HFRLM), is presented, which is based on the surface renewal theory, and integrates the advantages of fiber membrane extraction, liquid film permeation and other liquid membrane processes. The results from the system of in show that the HFRLM process is very stable. The liquid membrane is renewed constantly during the process, the direct contact of organic droplets and aqueous phase provides large mass transfer area. These effects can significantly reduce the mass transfer resistance in the lumen side. Then the mixture of feed phase and organic phase flowing through the lumen side gives a higher mass transfer rate than that of stripping phase and organic phase, because the aqueous layer diffusion of feed phase is the rate-controlling step. The overall mass transfer coefficient increases with increasing flow rates and D2EHPA concentration in the organic phase, and with decreasing initial copper concentration in the feed phase. The overall mass transfer coefficient also increases with increasing pH in the feed phase, and reaches a maximum value at pH of 4.44, then decreases. Also, there is a favorable volume ratio of 20:1 to 30:1 for this process. Compared with hollow fiber supported liquid membrane and hollow fiber membrane extraction processes, HFRLM process has a high mass transfer rate. Mathematical model for the HFRLM process based on the surface renewal theory is developed. The calculated results are in good agreement with experimental results under the conditions studied. [Copyright &y& Elsevier]

Abstract: Mg–Nd coatings were prepared by high-energy micro-arc alloying (HEMAA) on AZ31 magnesium alloy. The coatings were treated with Ar shielding gas in ambient atmosphere. X-ray diffraction (XRD) results showed that the phases formed of Mg–Nd coatings were similar to that of Mg–Nd electrode. The corrosion behavior of the coated AZ31 in 3.5wt% NaCl solutions was studied by simple immersion test and potentiodynamic polarization measurement. It was found that the corrosion resistance of coated alloy was higher than that of AZ31 substrate. The corrosion potential of Mg–Nd coatings was much positive to that of AZ31 substrate. Furthermore, the corrosion resistance is bad due to the presence of defects when treated with undesired processing parameters. [Copyright &y& Elsevier]