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Cesium lead halide perovskite nanocrystals (PNCs) have attracted great attention in optoelectronic devices due to their excellent optical properties, such as tunable emission wavelengths, long carrier lifetime, and narrow full width at half-maximum (fwhm). However, the poor stability of PNCs in water or humid environments greatly limits their wide-spreading applications. It is challenging to prepare PNCs with long-term stability in water. Herein, we successfully prepared CsPbBr3@PDMS microspheres by using the emulsification method. Due to the protection of the PDMS layer, the CsPbBr3@PDMS microspheres exhibit good optical properties and stability in water, acid, and alkali solutions. In addition, to expand the application of CsPbBr3 NCs in flexible optical devices and wearable devices, we first prepared stretchable, stable, and photoluminescent hydrogel with a CsPbBr3@PDMS microsphere (hydrogel/CsPbBr3@PDMS) by using the emulsification method. The hydrogel/CsPbBr3@PDMS elastomer exhibits good stability and stretchability. Furthermore, the hydrogel/CsPbBr3@PDMS elastomer retains bright green emission and stability under different mechanical deformations. This work provides a method to improve the CsPbBr3 PNCs with high stability by emulsification, which could also expand the applications of PNCs in underwater display, wearable, and flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Smart window based on lateral driving electrophoretic display. • Smart window exhibits fast response (375 ms) and high transmittance (78%). • Microcup effectively mitigate the lateral diffusion of particles. • Colorization of smart windows based on color electrophoretic particles. Smart windows can dynamically control the optical transmittance of natural light and efficiently reduce the energy consumption of buildings. Currently, the practical application of smart windows is limited by high power consumption, low transmittance, and complicated preparation process. Developing smart windows with fast response and high transmittance is challenging. Herein, we fabricated a smart window based on electrophoretic display (EPD) technology, which can switch between white and transparent states by changing the stacking states of the electrophoretic particles on electrodes. To further increase the transmittance of the smart window, the polyvinyl alcohol (PVA) hydrophilic layer was spin-coated on the electrode to reduce the adhesion of particles. Compared with other EPD smart window technologies, our device exhibits the fastest response time of up to 375 ms at 30 V, high transmittance of up to 78% at 632 nm, and a high contrast ratio of up to 89. In addition, to reduce the particle's lateral diffusion and improve our device's stability, the microcup array was aligned on the interdigital electrode. The particles can be driven and stacked onto the side walls of the microcup to achieve a transparent state. This work demonstrated that the EPD device would provide a promising future for practical smart windows with high transmittance and fast response time. [ABSTRACT FROM AUTHOR]

A kind of chemical sand consolidation system, which is stable with low density and good rheology, has been developed by single factor way, and its formula is 0.4%AOS+3% solid particle foam stabilizer +8% firming agent +0.3% coupling agent +60% epoxy emulsion. Then consolidation properties of foamed consolidation system are evaluated and effects of consolidating temperature, consolidating time and mean sizes of quartz sands on consolidation performances has been examined. It turns out that the prepared consolidation system has excellent consolidating effects with a temperature range of 60 ℃ to 90 ℃ and the compressive strength of consolidated column can reach 9.5 MPa. In addition, material resistance of consolidated column has been investigated, and the results show that the system has good resistance to acid, alkali, water and oil, displaying nice reservoir adaptation. [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (MoO3) suffers from poor conductivity, a low rate capability, and unsatisfactory cycling stability in lithium‐ion batteries. The aliovalent ion doping may present an effective way to improve the electrochemical performances of MoO3. Here, it is shown, by first‐principle calculations, that doping MoO3 with V by 12.5% can modulate significantly electronic structure and provide a small diffusion barrier for enhancing the electrochemical performance of MoO3. The ultralong Mo0.88V0.12O2.94 nanostructures, which retain the h‐MoO3 structure and present an exceptionally high conductivity and fast ionic diffusion due to the substitution of V, facilitating lithiation/delithiation behavior, and induce a fine nanosized structure with a reduced volume change are prepared. As a result, the stress and strain are alleviated during the Li‐ion intercalation/deintercalation processes, improving the cycling stability and rate capability. Such a large improvement in the electrochemical properties can be ascribed to the stabilizing effect of V, the small migration energy barrier, and short diffusion path, which arise from the introduction of V into MoO3. The unique engineering strategy and facile synthesis route open up a new avenue in modifying and developing other species of electrode materials. The fabrication of mixed Mo‐V oxides, according to theoretical calculations and experimental approaches, has a unique electronic structure and small diffusion barrier, leading to a more superior electrochemical performance compared to that of molybdenum oxides. In addition, the unique engineering strategy and facile synthesis route establish new avenues for the modification and construction of other electrode materials. [ABSTRACT FROM AUTHOR]

In the age of Internet of Things, electrophoretic electronic paper (E-paper) holds a unique position in the display area due to its energy-saving, environmental friendliness, excellent readability in strong ambient light, and eye protection. Compared with E-papers of microcapsules, microcups have several advantages including higher mechanical strength, lower production costs, and better feasibility to show multiple colors with high contrast, thereby making it a significant research interest. However, there is currently no systematic study on the structural mechanics and display performances of microcups. Herein, we simulate the structural stability of microcups with various shapes and sizes during nanoimprint process, and also calculated the aperture ratio of these microcups. We fabricated devices with different geometrical morphologies to verify the microcups for achieving a balance between high contrast, high transmittance and high structural stability. This study provides a new method for designing and manufacturing the E-papers of microcups in using nanoimprint roll-to-roll (R2R) production.