Ammonia-sensitive halide CsCuI film for gas sensor and stimuli-responsive anti-counterfeiting.

Eco-friendly lead-free halide perovskites have emerged as promising materials for multiple applications due to their unique optoelectronic properties. In this work, we investigate the ammonia (NH)-sensitive CsCuI film for its potential in NH sensor and stimuli-responsive fluorescence anti-counterfeiting. CsCuI-based NH sensor demonstrates a high response to NH (△R/R = 1.

Mesoporous Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) as Efficient Iodine Host for High-Performance Zinc-Iodine Batteries.

Here, by introducing polystyrenesulfonate (PSS) as a multifunctional bridging molecule to synchronously coordinate the interaction between the precursor and the structure-directing agent, we developed a mesoporous conductive polymer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) featuring adjustable size in the range of 105-1836 nm, open nanochannels, large specific surface area (105.5 m g), and high electrical conductivity (172.9 S cm).

Tuning electron delocalization of hydrogen-bonded organic framework cathode for high-performance zinc-organic batteries.

Stable cathodes with multiple redox-active centres affording a high energy density, fast redox kinetics and a long life are continuous pursuits for aqueous zinc-organic batteries. Here, we achieve a high-performance zinc-organic battery by tuning the electron delocalization within a designed fully conjugated two-dimensional hydrogen-bonded organic framework as a cathode material. Notably, the intermolecular hydrogen bonds endow this framework with a transverse two-dimensional extended stacking network and structural stability, whereas the multiple C = O and C = N electroactive centres cooperatively trigger multielectron redox chemistry with super delocalization, thereby sharply boosting the redox potential, intrinsic electronic conductivity and redox kinetics.

Solution-based self-assembly synthesis of two-dimensional-ordered mesoporous conducting polymer nanosheets with versatile properties.

Conducting polymers with conjugated backbones have been widely used in electrochemical energy storage, catalysts, gas sensors and biomedical devices. In particular, two-dimensional (2D) mesoporous conducting polymers combine the advantages of mesoporous structure and 2D nanosheet morphology with the inherent properties of conducting polymers, thus exhibiting improved electrochemical performance. Despite the use of bottom-up self-assembly approaches for the fabrication of a variety of mesoporous materials over the past decades, the synchronous control of the dimensionalities and mesoporous architectures for conducting polymer nanomaterials remains a challenge.

Polyoxometalate-Bridged Synthesis of Superstructured Mesoporous Polymers and Their Derivatives for Sodium-Iodine Batteries.

Despite the impressive progress in mesoporous materials over past decades, for those precursors having no well-matched interactions with soft templates, there are still obstacles to be guided for mesoporous structure via soft-template strategies. Here, a polyoxometalate-assisted co-assembly route is proposed for controllable construction of superstructured mesoporous materials by introducing polyoxometalates as bifunctional bridge units, which weakens the self-nucleation tendency of the precursor through coordination interactions and simultaneously connects the template through the induced dipole-dipole interaction. By this strategy, a series of meso-structured polymers, featuring highly open radial mesopores and dendritic pore walls composed of continuous interwoven nanosheets can be facilely obtained.

Surface Reconstruction of CsPbBr Nanocrystals by the Ligand Engineering Approach for Achieving High Quantum Yield and Improved Stability.

Oleylamine/oleic acid (OAm/OA) as the commonly used ligand is indispensable in the synthesis of perovskite nanocrystals (PNCs). Unfortunately, poor colloidal stability and unsatisfactory photoluminescence quantum yield (PLQY) are observed, resulting from a highly dynamic binding nature between ligands. Herein, we adopt a facile hybrid ligand (DDAB/ZnBr) passivation strategy to reconstruct the surface chemistry of CsPbBr NCs.

Volatile organic compound removal by post plasma-catalysis over porous TiO with enriched oxygen vacancies in a dielectric barrier discharge reactor.

Non-thermal plasma (NTP) degradation of volatile organic compounds (VOCs) into CO and HO is a promising strategy for addressing ever-growing environment pollution. However, its practical implementation is hindered by low conversion efficiency and emissions of noxious by-products. Herein, an advanced low-oxygen-pressure calcination process is developed to fine-tune the oxygen vacancy concentration of MOF-derived TiO nanocrystals.

Dual-channel geometric meta-holograms with complex-amplitude modulation based on bi-spectral single-substrate-layer meta-atoms.

Metasurfaces with complex-amplitude modulation are superior in power regulation and hologram imaging resolution compared with those with phase-only modulation. Nevertheless, a single-cell metasurface with multi-band independent phase and amplitude controls is still a great challenge for the circularly polarized incidences. In this work, we propose and design a single-substrate-layer single-cell metasurface with independent complex-amplitude modulations at two discrete frequencies.

Polypyrrole Cubosomes with Ordered Ultralarge Mesopore for Controllable Encapsulation and Release of Albumin.

Despite substantial progress in porous materials over past years, controllable preparation of conductive polymers (CPs) with continuous large pores is challenging, which are important for diverse applications, including energy storage, electrocatalysis, and biological separations. Here, we develop an unprecedented ordered bicontinuous mesoporous PPy cubosomes (mPPy-cs) using a soft-template strategy, resulting in ultralarge pores of ∼45 nm and high specific surface area of 69.5 m g.

Design, fabrication, and characterization of a single-polarization single-mode flexible hollow waveguide for low loss millimeter wave propagation.

A flexible metallic waveguide with elliptical core that achieves single-polarization single-mode (SPSM) propagation at millimeter wave was designed, fabricated, and characterized. In order to achieve SPSM propagation, optimization of the lengths of major/minor axes of elliptical core was conducted to cut off one of the two orthogonally polarized fundamental modes and all high-order modes. A one-meter long hollow elliptical waveguide (HEW) with major/minor axis length of 1.

Controlled Synthesis of Mesoporous π-Conjugated Polymer Nanoarchitectures as Anodes for Lithium-Ion Batteries.

Conjugated polymers possess better electron conductivity due to large π-electron conjugated configuration endowing them significant scientific and technological interest. However, the obvious deficiency of active-site underutilization impairs their electrochemical performance. Therefore, designing and engineering π-conjugated polymers with rich redox functional groups and mesoporous architectures could offer new opportunities for them in these emerging applications and further expand their application scopes.

Anomalous NH-Induced Resistance Enhancement in Halide Perovskite MAPbI Film and Gas Sensing Performance.

Despite the growing interest in halide perovskite-based NH sensors, the NH sensing mechanism is still not well understood. Here, we report an anomalous behavior of resistance enhancement in CHNHPbI(MAPbI) perovskite films upon exposure to NH gas, which is contrary to a resistance drop trend in previously reported perovskites. We propose a NH sensing mechanism in which the anomalous resistance enhancement is dominated by grain boundaries of perovskites.

Modulation of Ferroelectric and Optical Properties of La/Co-Doped KNbO Ceramics.

The phase transition, microscopic morphology and optical and ferroelectric properties are studied in a series of La- and Co-doped KNbO-based ceramics. The results show that the doping induces the transformation from the orthorhombic to the cubic phase of KNbO, significantly reduces the optical bandgap and simultaneously evidently improves the leakage, with a slight weakening of ferroelectric polarization. Further analysis reveals that (i) the Co doping is responsible for the obvious reduction of the bandgap, whereas it is reversed for the La doping; (ii) the slight deterioration of ferroelectricity is due to the doping-induced remarkable extrinsic defect levels and intrinsic oxygen vacancies; and (iii) the La doping can optimize the defect levels and inhibit the leakage.

Nanoarchitectured Porous Conducting Polymers: From Controlled Synthesis to Advanced Applications.

Conductive polymers (CPs) integrate the inherent characteristics of conventional polymers and the unique electrical properties of metals. They have aroused tremendous interest over the last decade owing to their high conductivity, robust and flexible properties, facile fabrication, and cost-effectiveness. Compared to bulk CPs, porous CPs with well-defined nano- or microstructures possess open porous architectures, high specific surface areas, more exposed reactive sites, and remarkably enhanced activities.

Transmission and imaging characteristics of flexible gradually tapered waveguide at 0.3 THz.

Flexible gradually tapered metal waveguides (GTMWs) are fabricated by an inner plating silver film in a polycarbonate (PC) capillary for the transmission and imaging at 0.3 THz. It was demonstrated theoretically and experimentally that GTMWs have lower transmission losses and smaller additional losses of bending, comparing with thin constant bore metal waveguides (CBMWs).

General Construction of 2D Ordered Mesoporous Iron-Based Metal-Organic Nanomeshes.

Nanomeshes with highly regular, permeable pores in plane, combining the exceptional porous architectures with intrinsic properties of 2D materials, have attracted increasing attention in recent years. Herein, a series of 2D ultrathin metal-organic nanomeshes with ordered mesopores is obtained by a self-assembly method, including metal phosphate and metal phosphonate. The resultant mesoporous ferric phytate nanomeshes feature unique 2D ultrathin monolayer morphologies (≈9 nm thickness), hexagonally ordered, permeable mesopores of ≈16 nm, as well as improved surface area and pore volume.

Hollow Bio-derived Polymer Nanospheres with Ordered Mesopores for Sodium-Ion Battery.

Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials. However, the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure. Here, we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy, using phytic acid-based natural compounds as an example, for the spatially controlled fabrication of metal coordination bio-derived polymers.

Sodium citrate doped polypyrrole/PS glass capillary tube sensor for ultra-small volume HCl gas detection.

A sodium citrate (SC) doped polypyrrole (PPy)/PS capillary sensor was prepared for ultra-small volume HCl gas detection. A PS film was formed in advance on the inner wall of a silica glass capillary tube, which enabled us to prepare a high-qualified PPy sensitive film inside the tube. The crystallinity, morphology, microstructure and carrier transport properties of the PPy film were characterized by XRD, SEM, FTIR and Hall effect system, respectively.

Preparation and transmission characteristics of a mid-infrared attenuated total reflection hollow waveguide based on a stainless steel capillary tube.

Stainless steel (SUS) capillary tubes were examined as a category of structural tube for establishing a metallic attenuated total reflection (ATR) GeO hollow waveguide. GeO films were grown on the inner wall of SUS tubes by different liquid phase deposition (LPD) cycles. Fourier transform infrared (FTIR) spectra, scanning electronic microscope (SEM) image, and transmission loss for a CO laser were measured to investigate the effects of the LPD cycles on the transmission behavior of the hollow waveguide samples.

Fabrication and characteristics of porous germanium films.

Porous germanium films with good adhesion to the substrate were produced by annealing GeO ceramic films in H atmosphere. The reduction of GeO started at the top of a film and resulted in a Ge layer with a highly porous surface. TEM and Raman measurements reveal small Ge crystallites at the top layer and a higher degree of crystallinity at the bottom part of the Ge film; visible photoluminescence was detected from the small crystallites.

Aqueous germanate ion solution promoted synthesis of worm-like crystallized Ge nanostructures under ambient conditions.

This work demonstrates that it is possible to synthesize crystallized Ge nanostructures directly in an aqueous medium under ambient conditions by using widely available GeO2 (in the form of germanate ions) as a precursor. The reaction of germanate ions with NaBH4 in an aqueous medium resulted in highly hydrogenated Ge that could be transformed into crystallized Ge after an air-drying treatment. The NaBH4/GeO2 molar ratio, reaction time and drying temperature were optimized for the synthesis of crystallized Ge products.

[Raman spectra study on the GeS2-Ga2S3-KCl system glasses].

Raman spectra of GeS2 -Ga2S3-KCl pseudo-ternary system glasses at room temperature in the air were probed systematically in the region of 150-500 cm(-1). Based on the results of Raman spectra and preparing procedure in pseudo-binary systems GeS2 -KCl and Ga2S3 -KCl, the sole interaction of Ga2S3 and KCl was identified and new units GaS3/2 Cl were produced in GeS2 -Ga2S3-KCl glasses. That K+ ions in the form of Cl as the nearest coordination were homogeneously dispersed in the polymeric network was confirmed by the Raman spectra evolution of samples on the serials I and Ill.