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Zinc-ion batteries (ZIBs) have attracted significant attention owing to their high safety, high energy density, and low cost. ZIBs have been studied as a potential energy device for portable and flexible electronics. Here, a highly flexible free-standing Zn anode is fabricated using a simple spin-coating technique, and its application in ZIBs is demonstrated. The free-standing Zn anode precursor is formed by mixing Zn particles with carbon nanotubes and poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP). The hexafluoropropylene group in PVDF-HFP improves the mechanical properties of the free-standing Zn anode, whereas the carbon nanotubes created percolation conduction in the composite electrode, leading to an increased electrical conductivity of the anode. Owing to the excellent electrical conductivity and high specific surface area of the free-standing Zn anode, ZIBs with high capacity, rate performance, and mechanical flexibility are achieved. The volumetric energy density of the ZIBs reaches 8.22 mW h cm-3 with a battery thickness of 0.4 mm. This work demonstrates that free-standing Zn anodes are promising anodes for flexible ZIBs.

Stable and reliable electrical properties of interconnects and interfaces between flexible/stretchable and rigid materials/components are essential for the practical applications of flexible electronic devices and systems; traditional metal thin films and hard solder interconnects and interfaces can no longer meet these requirements. As an emerging soft conductive material, liquid metal has the advantages of high stretchability, flexibility, etc. over other soldering materials, and it has been used in interconnects and interfaces for some flexible electronics. In this study, we report a detailed investigation on the reliability and stability of liquid metal-based interconnects/interfaces under various mechanical deformations, including extension, bending, torsion, high frequency vibration and high temperature operation; we also compared the results with those of interconnects and interfaces using silver paste, the most commonly used solder for flexible electronics. The results show that liquid metal interconnects and interfaces maintain high conductivity under severe elongation up to 95% and 130%, upon bending with a curvature radius as low as ∼1.5 mm, and upon twisting up to 360°; meanwhile, interconnects and interfaces with silver paste filler lose electrical conductivity at elongations of 0.6% and 60%, respectively. Liquid metal interconnects and interfaces show superior performance to silver paste interconnects and interfaces because liquid metal can be re-shaped to make good contact with objects, while the silver paste becomes solid and rigid once dried and thus loses contact with other objects under deformation.

Perovskite-based photodetectors have great potential in light-signal conversion; the suppression of the dark current is regarded as one of the main concerns within the academic research communities to achieve a high-performance photodetector. Interfacial engineering in the transport layer is considered as one of the most essential methods for enhancement of perovskite photodetectors. Here, a nanocomposite thin film of tetra-sulfonated copper phthalocyanines and reduced graphene oxide (TS-CuPc/rGO) was investigated as the interfacial layer in perovskite-based photodetectors. Photodetectors with the TS-CuPc/rGO thin film as the interfacial layer exhibited a low dark current density of 2.2 × 10−8 A cm−2 at bias of −0.1 V as well as high responsivity and detectivity of ∼357 mA W−1 and ∼4.2 × 1012 jones, respectively; moreover, we observed an ON/OFF ratio of 7.33 × 103 to 520 nm light with an intensity of ∼0.077 mW cm−2. Our study revealed that with rGO additives, TS-CuPc molecules were favorable for the formation of an edge-on stacking film with high crystallinity. The rGO-induced crystalline TS-CuPc thin film with lower crystallographic defects effectively reduced the carrier recombination rate at the interfaces, leading to a suppressed dark current and enhanced photocurrent in the photodetector device, when compared to the less crystalline TS-CuPc layer.

The toxicity and radioactivity of uranium [235,238U(VI)] has resulted in serious environmental issues in recent years. Polyethyleneimine-decorated waste fly ash (FA@PEI) from thermal power plants has been fabricated via a novel and cost-efficient method and applied to the U(VI) elimination from aqueous solutions by batch experiments. The U(VI) removal was found to be dramatically influenced by pH whilst being ionic strength-independent, which indicated that the interaction was primarily controlled by inner-sphere surface complexation. Kinetic studies showed that the FA@PEI had an ultrafast removal rate (1.5 h to achieve adsorption equilibration) for U(VI) and a pseudo-second-order model fitted the adsorption process. The maximum removal capacity of U(VI) by FA@PEI was 70.3 mg g−1 at 298 K and pH 5.0. Based on the thermodynamics data (ΔH° > 0, ΔS° > 0 and ΔG° < 0), the U(VI) removal process is typically spontaneous and endothermic. According to the XPS analysis, the enhanced U(VI) adsorption was mainly attributed to the abundant metal–oxide bonds and amine groups (–NH2, –NH–). Furthermore, the FA@PEI material also demonstrated an outstanding regeneration ability. This paper highlights FA@PEI as an environmentally-friendly and economical alternative for U(VI) elimination from waste water.

This paper demonstrates the development and validation of a high-performance liquid chromatography (HPLC) method for the determination of pyrimethamine in fish and plasma samples using core–shell molecularly imprinted polymers (MIPs). The MIPs were synthesized based on thiol–ene click chemistry, using pentaerythritol tetra (3-mercaptopropionate) and dipentaerythritol pentaacrylate as binary cross-linkers, pyrimethamine as a template and methacrylic acid as a functional monomer. The MIPs were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The MIPs were used as matrix solid-phase dispersion extraction sorbents for the separation of pyrimethamine in fish and plasma samples. The results show that the developed MIPs had higher extraction capacity toward pyrimethamine than non-imprinted polymers (NIPs), high selectivity among pyrimethamine analogues, and a saturation capacity of 41.9 μmol g−1. Furthermore, the proposed method was validated for linearity, precision, accuracy, and it has been applied for the analysis of pyrimethamine in fish and plasma samples, obtaining satisfactory recoveries.

In the past few decades, uranium (235, 238U(VI)) has turned into a forefront environmental issue due to its extensive use in the nuclear industry and its toxicity and radioactivity. Herein, nanoscale zero valent iron (nZVI), which was supported on Ca–Mg–Al-layered double hydroxide (Ca–Mg–Al-LDH/nZVI), was fabricated via an in situ growth route and employed for U(VI) decontamination from aqueous solutions. Spectroscopy and microscopy (SEM, TEM, FTIR, XRD, BET, and XPS) technologies were applied for the investigation of the properties of Ca–Mg–Al-LDH/nZVI and the U(VI) elimination mechanism. Ca–Mg–Al-LDH/nZVI had a remarkable BET surface (426.8 m2 g−1), abundant functional groups (i.e., Fe–O, Al–O, –OH, etc.), high efficiency (4 h to achieve equilibrium) and large adsorption capacities (Qmax = 216.1 mg g−1) for U(VI) removal. The decontamination process of U(VI) was observed to be pH-dependent and ionic strength-independent, suggesting that the adsorption was predominated by inner-sphere surface coordination. XPS spectroscopy analyses indicated that the reduction and adsorption of nZVI and the adsorption of Ca–Mg–Al-LDH dominated U(VI) elimination on Ca–Mg–Al-LDH/nZVI. The environmentally friendly synthesis method, excellent physicochemical properties and remarkable removal performance suggested that Ca–Mg–Al-LDH/nZVI was applicable as a potential adsorbent for U(VI) decontamination from wastewater in environmental pollution remediation.