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We construct a highly efficient photocatalyst consisting of Ag3PO4 and α-Fe2O3 hybrid powders for the treatment of rhodamine B. The catalytic degradation efficiency reached 95% after 10 min.

Transition metal zinc sulfide (ZnS) is a promising anode material for potassium ion batteries due to its rich abundance and high capacity (conversion/alloy dual mechanism), while still suffering the drawbacks of sluggish kinetics process and structural degradation, which restrict its practical application. Herein, ZnS spheres assembled from nanoparticles embedded in carbon nanosheets (ZnS/C@C) were synthesized with alkali-activated agricultural waste bagasse as the carbon precursor. The removal of lignin and hemicellulose by pre-treatment of bagasse with alkali solutions opens ionic diffusion channels and promotes adsorption of Zn2+ by bagasse, which is crucial for the growth of ZnS in bagasse sheets and the suppression of ZnS particle size during hydrothermal processes. Benefiting from the synergistic effects between robust embedded structure, carbon conductive network and the nanoscale nature of ZnS, the ZnS/C@C exhibited enhanced performance with high capacity (374.7 mA h g−1 at 0.2 A g−1) and rate performance (195.9 mA h g−1 at 2.0 A g−1). Kinetic studies further demonstrate that ZnS/C@C electrodes possess faster K+ transport kinetics and lower interfacial impedance. This work provides a reference for the construction of robust embedded carbon composite structures based on surface control of agricultural waste.

Na-related anodes with excellent rate capability and ultra-stable cyclability are being pursued significantly to overcome the slow kinetics of currently available compounds on account that the sodium-ion battery is an ideal energy storage device technology for grid-scale electricity networks. Herein, we demonstrate a novel concept for the construction of a nanoarchitecture with robust charge transfer networks, which is composed of MoS2/C superstructure nanoflowers embedded in carbon nanonets (MoS2/C-CNNs). Impressively, the optimized nanoarchitecture exhibited an ultra-fast Na-ion storage feature, a superior reversible capacity of 245.2 mA h g−1 at 5 A g−1, and a promising retention of 78.9% after 8000 cycles. The interconnected 3D carbon nanonetworks, derived from the carbonization of sugarcane bagasse via a novel “self-splitting process”, were found to be extremely beneficial for the acceleration of electron transport and Na+ diffusion, while alleviating the volumetric strain of MoS2 during the Na+ insertion/extraction processes. Furthermore, computational analysis was performed to reveal the underlaid mechanism, demonstrating that the MoS2/C superstructures can significantly ameliorate the electronic conductivity of MoS2 and lower the Na+ diffusion barrier, which tend to facilitate the electron and Na+ transport at the atomic level. This work demonstrates that the construction of robust 3D ion/electron traffic networks at various scales is an efficient strategy to develop electrodes with adequate rate capability and remarkable cyclability.

Potassium–sulfur batteries in carbonate-based electrolytes cannot work well due to side reactions between polysulfide ions and ester molecules. Currently, removing superficial sulfur is an effective way to solve this issue. Here, we successfully achieved the deep encapsulation of sulfur and removal of superficial sulfur by a simple filtration-washing approach. As expected, the obtained products exhibited improved electrochemical stability and are promising candidates for better potassium–sulfur batteries.

Inferior electrical conductivity and large volume variation are two disadvantages of metal selenides. In this work, we have designed a core–shell structure of FeSe2@C composite with low cost using facile hydrothermal method. The FeSe2 particles as the ‘core’ and the carbon layer as the ‘shell’ displayed good synergistic effect that attributed to alleviate volume expansion of electrode and improving the electrical conductivity, which achieved the fast potassium storage. The core–shell structural FeSe2@C electrode achieved 286 mA h g−1 at 1 A g−1 over 1000 cycles with 99.8% coulombic efficiency and delivered excellent rate capacity with 273 mA h g−1 at 2 A g−1, which was ascribed to dispersed FeSe2 particles and the strong carbon shell coating. This work will provide the basis for the further development of the application of metal selenides in the field of flexible electrodes.

Novel perpendicularly cross-rectangular CuO architectures have been successfully fabricated on a large scale by a facile microwave-assisted chemical aqueous route. The as-synthesized CuO products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM) and UV-vis absorption spectroscopy. An individual CuO microstructure is mainly assembled by two rectangle-shaped nanosheets with different sizes, which is perpendicularly intersected through the center. A possible formation mechanism of perpendicularly cross-rectangular CuO architectures was proposed based on the comparative experimental results. The prepared CuO nanoarchitectures exhibited excellent photocatalytic activity for the decolorization of Rhodamine B (RhB) under visible light irradiation. Simultaneously, the prepared CuO products, acting as an additive, also showed effective catalytic activity on the thermal decomposition of ammonium perchlorate (NH4ClO4).

A mild one-pot hydrothermal route has been successfully designed to controllably prepare orthorhombic alpha-MoO3 nanobelts and monoclinic MoO2 microaxletrees respectively by adjusting the dosage of (NH4)6M07O24 x 4H2O (AHM). The products are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-visible absorption spectrum. The as-prepared alpha-MoO3 nanobelts, with widths of 100-400 nm and lengths up to 30-40 microm, grow along [001] direction. The as-obtained MoO2 microaxletrees are assembled by countless nanolaths with the thickness of 80-150 nm. The chemical reaction processes for the formation of MoO(x) (MoO3 and MoO2) phases are investigated based on the experimental phenomena. The possible growth mechanisms are also discussed. The band gap energies (E(g)) of the obtained alpha-MoO3 nanobelts and MoO2 microaxletrees are calculated to be 2.90 and 3.72 eV, respectively. This work exhibits an effective approach in the selectively controlled synthesis of MoO(x) (x = 2, 3) nanomaterials via one-step hydrothermal strategy.

Hierarchically structured hollow microspheres composed of copper sulfide (CuS) nanoplatelets have been successfully fabricated via a one-pot and green sonochemical process for the first time, using copper acetate and thiourea aqueous solution as precursors without surfactant or template. Large-scaled hollow architectures with outer diameters in the range of 1–1.2 μm are assembled by pure hexagonal single crystalline CuS nanoplatelets, being of about 20 nm in thickness with stacking faults in the crystal lattice. The UV-Vis diffuse reflectance spectra (DRS) analysis suggests that the band gap energy of the as-obtained CuS sample was estimated to be 1.27 eV, showing a significant red-shift compared with the bulk value. Hollow CuS structures possess the high surface area and double pore size distributions as measured from the N2 adsorption isotherms. Moreover, the possible growth mechanism for CuS hollow spheres is proposed on the basis of the temporal evolution controlled experiments. More importantly, this hierarchically structured CuS catalyst show highly efficient Fenton-like catalytic activity in degrading highly concentrated dye-containing solution (50 mg·mL−1) with the help of hydrogen peroxide (H2O2), suggesting a promising application in wastewater purification.

Porous hematite (α-Fe 2 O 3 ) nanomaterials can be simply acquired from amorphous iron (III) hydroxide (Fe (OH) 3 ) in neutral solution by an evaporation method in an open quartz flask in a vacuum drying oven. Results show that the as-obtained α-Fe 2 O 3 particles at 180°C for 2h or so are nearly spindle in shape. Each of α-Fe 2 O 3 microspindles is made of many ultrafine α-Fe 2 O 3 nanoparticles and results in a porous structure. The as-prepared porous α-Fe 2 O 3 powders have higher surface area (~78m 2 /g) and can rapidly remove Cr (VI) ions in wastewater at room temperature. The model of the adsorption kinetic of Cr (VI) is best adapted to the pseudo second-order equation. Keywords: Hematite, Thermal evaporation, Porous structure, Removal of Cr (VI) e-mail: hfuuhan@163.com 1. For Cr (VI) -adsorption: The aqueous solutions with constant Cr (VI) INTRODUCTION The design and synthesis of various morphologies nanostructures have been important research subjects in nanoscience and nanotechnology due to their unique size and shape-dependent chemical and physical properties. Nanosturctured hematite (α-Fe

Hierarchical semiconductor CuO nanotablets with pores have been fabricated on a large scale by a facile and one-pot sonochemical process using the copper acetate and ammonia aqueous solution as precursor in the absence of surfactants or additives. The as-synthesized products were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM), selected area electron diffraction (SAED), and N2 physisorption. The results reveal that porous tablet-shaped CuO nanostructures composed of nanoribbons possess a monoclinc phase CuO with the average diameters about 200 nm and around 50 nm in thickness. The Brunnauer-Emmett-Teller (BET) specific surface area and the single point adsorption total pore volume were measured to be 26.8 m2/g and 0.083 cm3/g, respectively. The band-gap energies were estimated to be 2.52 eV from a UV-vis absorption spectrum, which showed the quantum size effects of the nanosized semiconductors. A possible mechanism for porous CuO nanotablets was discussed.