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A new type of adsorbent, a Prussian blue analog-based copper–aluminum layered double hydroxide (PBA@CuAl-LDH), was successfully synthesized using a one-step method for the removal of radioactive Cs+ from wastewater. The adsorption performance, characteristics and the underlying adsorption mechanism of PBA@CuAl-LDH were systematically examined. The results showed that PBA@CuAl-LDH exhibited excellent adsorption performance, with a maximum adsorption capacity of 109.2 mg g−1. Over 85% of PBA@CuAl-LDH can be recycled, and the material exhibited only a 6.6% loss in adsorption performance. The adsorption process was well-fitted using the pseudo-second-order kinetic model and the Freundlich isotherm model, revealing the surface heterogeneity of the composite adsorbent. A molecular model of PBA@CuAl-LDH was constructed by combining density functional theory and multiple instrumental characterization techniques. Our results indicate that PBA crystals can be generated between layers and on the surface. Ion exchange was revealed as the main adsorption mechanism of Cs+ by PBA@CuAl-LDH. Specifically, the interstitial spaces of the PBA crystals generated between the layers and on the surface played an important role in ion exchange. These findings provide concrete theoretical support for radioactive pollution control and have significant value in directing the fabrication of cesium removal materials and their future engineering application. [ABSTRACT FROM AUTHOR]

The preparation of single crystals, especially large-size ones, is highly important but challenging. Herein, exploiting the special nucleation and growth environment provided by the Marangoni effect, we synthesised oriented centimetre-sized Zn-MOF crystals. These large-size single crystals can be employed for separation of mixed-ionic dyes without any further processing. This work opens up a brand-new avenue for the synthesis of large-size single-crystals. [ABSTRACT FROM AUTHOR]

We report a one-step method to fabricate a free-standing supramolecular membrane composed of melamine and barbituric acid coordinated with silver nitrate (Mba–Ag) at the gas/liquid interface by a soft spray technique. MBa–Ag exhibits a folded two-dimensional layered morphology and thickness of 4.5 μm. The shortwave IR transmittance of MBa–Ag is as high as 95%, which is much higher than the transmittance of UV and visible light, and has the potential for electromagnetic wave transmission. [ABSTRACT FROM AUTHOR]

Dynamic plasmonic color displays have been proposed as an outstanding candidate for the next generation of color displays due to their ultrahigh resolution and tunable optical color display performance. Herein, we propose an effective indirect "layer-by-layer" (LBL) building strategy for the fabrication of a responsive metal–insulator–metallic nanoarray (MIMn) cavity with dynamic plasmonic color display performance. The responsive MIMn cavity is constructed through preparing a bottom metal layer, a middle pH-responsive hydrogel layer, and a top metallic array subsequently based on a film preparation technique and nanostructure transfer technique. By controlling the structural parameters of the middle hydrogel layer, the plasmonic color of the as-prepared MIMn cavity can be well-tuned. What is more, owing to the pH-responsiveness of the middle hydrogel layer, the as-prepared MIMn cavity shows dynamic color display performance with facile controllability and good reproducibility. The proposed "layer-by-layer" building strategy not only preserves the structure and responsiveness of the middle hydrogel, but also realizes the precise control of the top metallic array. Together with the excellent dynamic features of the as-prepared MIMn cavity, it is believed that the proposed "layer-by-layer" building strategy will pave a new way to fabricate dynamic plasmonic color display materials for various application fields such as optical sensors, display devices, and activity monitors. [ABSTRACT FROM AUTHOR]

Epitaxial metal–organic framework (MOF) films have shown huge potential for use in separation applications. Herein, bendable epitaxial MOF films are fabricated via spraying. The synthesized MOF films show excellent oil-in-water emulsion separation performance even after being bent for multiple times at high curvatures. [ABSTRACT FROM AUTHOR]

Photonic paper with dynamically tunable color has been widely investigated due to its excellent ability to change its optical patterns under external variation. Herein, a UV-responsive metal–insulator–metal (MIM) Fabry-Perot cavity is proposed to prepare dynamic photonic paper through introducing disulfide bonds containing polyurethane as an insulating layer. The as-prepared MIM cavity based photonic paper shows dynamically tunable color variation in almost the whole visible gamut under different UV-irradiation durations. In addition, by simply adjusting the UV-irradiation duration at each point with the aid of a photomask, multicolor patterns could be "written" onto the as-prepared MIM photonic paper. What's more, thanks to the dynamic feature of the disulfide bond, the color patterns on the photonic paper could also be "erased" by thermal treatment, making the photonic paper "rewritable". Together with all these features, the proposed UV-responsive MIM photonic paper would exhibit great potential for application in information anticounterfeiting, dynamic color display devices and environment-friendly inkless color printing. [ABSTRACT FROM AUTHOR]

Building CuO hierarchical structures with precisely controlled micro/nano scale features remains a great challenge, although this plays a vital role in optimizing their performance in specific applications, such as gas sensing. Herein, two CuO hierarchical morphologies have been successfully prepared via the pyrolysis of different metal–organic framework (MOF) precursors with similar chemical compositions but different morphologies. The relationship between MOF precursors and micro- and nano-scale structural features of the yielded hierarchical structures has been revealed in detail. The micro scale feature of the cube-like MOF is easier to retain than that of the rod-like MOF after pyrolysis. The nanoscale feature of the obtained CuO hierarchical structures is determined by the size of the MOF precursor structure in the radial direction. In addition, the obtained two CuO hierarchical morphologies exhibited better gas sensing performance than the other CuO morphologies because of their structural stability and porosity. Meanwhile, the sensors with rod-like CuO hierarchical morphology display better sensing performance than the cube-like CuO sensors because of the synergistic effect of the micro and nano scale structural features in rod-like CuO, shedding light on the structure–function relationship of CuO hierarchical morphologies in gas sensing. [ABSTRACT FROM AUTHOR]

An ordered pattern or a distinct texture on surfaces endows materials with specific applications, such as oil–water separation, advanced anticounterfeiting and optical devices. Conventional photolithography and surface patterning methods can form only 2D patterns, and they are also limited by the shape of a material and the required equipment. In this study, a swelling-induced 3D photopatterning (SPP) method is demonstrated to manipulate both the shape and surface pattern of a material. Under the irradiation of visible light, metathesis of diselenide bonds induces different swelling behaviors between irradiated and nonirradiated regions. Based on the differences, various programmable 3D patterns are obtained. Notably, the SPP method is not limited by the size and shape of the material; therefore, this method can be applied to thin film materials, bulk materials and cylindrical materials. In addition, this strategy has potential applications in advanced anticounterfeiting. [ABSTRACT FROM AUTHOR]