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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.

The hierarchical binary CdS/NiO hollow heterogeneous architectures (HHAs) with p-n heterojunction are constructed by a facile microwave-assisted wet chemical process for high-efficient photocatalytic hydrogen evolution reaction (HER) from water. The asdesigned CdS/NiO HHAs are composed of hexagonal n-type CdS nanoparticles with a size in the range of 20–40 nm attaching to cubic p-type NiO hollow microspheres (HMSs) which are aggregates of porous nanoplates with a thickness of about 20 nm. The photocatalytic water splitting over CdS/NiO HHAs is significantly increased under simulated solar irradiation, among which the most active sample of CdS/NiO-3 (the mass ratio of CdS to NiO is 1:3) exhibits the fastest photocatalytic HER rate of 1.77 mmol·g−1·h−1, being 16.2 times than that of pure CdS. The boosted photocatalytic HER could be attributed to the synergistic effect on the proportional p-n heterojunction with special hierarchical hollow and porous morphology, an enhancement of visible light absorption, and an improvement of photoinduced charge separation as well as the photo-stability given by the composite heterojunction. This work shows a viable strategy to design the heterojunction with special morphology for the efficient hydrogen generation by water splitting utilizing solar energy.

The introduction of oxygen vacancies (Ov) into photoanodes has been considered an effective method to enhance the photoelectrochemical (PEC) water splitting performance. The efficiency of water splitting is related to light absorption, charge separation to the electrode surface, and charge injection into the electrolyte. However, introducing Ov from a single level cannot meet the above objectives. In this work, we present the fabrication of BiVO

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.

Three types of hierarchical CuO architectures with the varying (111) facets exposure were controllably fabricated by a microwave-assisted wet chemical route. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, transmission electron microscopy (TEM), and high-resolution TEM. The results demonstrate that the monoclinic hierarchical pumpkin-like CuO (p-CuO) crystals are self-assembled by 1D nanoribbons primarily exposed (111) lattice planes with diameters of 6–7 nm. Specifically, the XRD peak intensity ratios of I111/I− 111 were calculated to be 1.38 for p-CuO, which is much larger than that of the other shuttle-like CuO (s-CuO) (1.01) and CuO microspheres (m-CuO) (0.92). The possible growth mechanism for the three kinds of CuO microstructures was proposed. Interestingly, it is a finding for the first time that the Fenton-like catalytic activities of the as-prepared CuO catalysts are closely relied on their preferential (111) facets exposure, in which the order of degradation rates of RhB, MB, and MO accords with the following: p-CuO > s-CuO > m-CuO. Significantly, the decoloring efficiency of RhB over p-CuO in the assistant of H2O2 was up to 93.7% within the initial 1 min, and the total removal rate reached 98.5% after 5 min, exhibiting the rapid and superior Fenton-like catalysis activity.

Hierarchical binary CdS/BiOCl heterostructures comprised of CdS nanoparticles (NPs) decorating on BiOCl nanoflakes (NFs) for the enhanced photocatalytic activity were fabricated by a facile two-step microwave-assisted aqueous chemical reaction. The chemical composition, morphology, crystal structure, and optical properties of the CdS/BiOCl nanostructures were characterized by various techniques. The results indicated that island-like CdS NPs with 10-30 nm in size are planted on the surface of BiOCl NFs primarily exposed {001}-facets with diameter in the range of 200–600 nm and thickness of about 30 nm. The possible growth mechanism for the satellite-core structured hybrid CdS/BiOCl architectures was proposed. Particularly, CdS/BiOCl-3 exhibited the superior photocatalytic activity for the decomposition of Congo red in high concentration under visible light irradiation, in which the pseudo-first-order kinetic rate constant was 2.33, 8.32 and 2.06 times higher than that of pure CdS, pristine BiOCl and the physical mixture. The promotion mechanism could be ascribed to the perfect band matching and efficient internal charge transfer within the engineered heterojunction, resulting in the lower carrier recombination loss and the longer lifetime of electron–hole pairs. Furthermore, the high photocatalytic performance for the degradation of malachite green and methyl red suggests a promising application in industrial wastewater purification.

One-dimensional (1D) hierarchically structured CdS nanoparticles (NPs)/NiO nanofibers (NFs) heterostructures with remarkable removal efficiency for diazo dye Congo red (CR) were fabricated by a stepwise synthesis process, which was involved a chemical bathing deposition combined with calcination, and a microwave-assisted wet chemical reaction. The crystal phases, morphologies, optical absorption properties, and adsorption/photocatalytic activity of as-prepared products were investigated by XRD, FESEM, TEM, high-resolution TEM (HRTEM), N2 adsorption/desorption isotherms, UV–Vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectrum respectively. The experimental results indicated that binary satellite- core CdS NPs/NiO NFs heterojunctions are comprised of n-type CdS NPs with size of 10–30 nm decorated onto 1D p-type NiO NFs with diameter of 60–180 nm and length up to microns, which are self-assembled by nanoparticles with 30–100 nm in size. The possible formation mechanism for satellite-core structured CdS/NiO heterojunction is proposed. Interestingly, the decolorization efficiency over CdS/NiO heterostructures reached up to 91.2% in removal of aqueous CR at high concentration within 40 min under visible light irradiation, which was approximately 5.2 and 3.8 times as high as that of pure CdS nanocrystals (NCs) and the mixture of NiO NFs and CdS NCs. Furthermore, the possible photocatalytic mechanism was also investigated. The as-designed hybrid CdS NPs/NiO NFs heterostructures exhibited improved photocatalytic activity, which is attributed to the enhancement of the visible light adsorption, the efficient separation of photogenerated electrons and holes, and the high adsorption capacity towards CR molecules, thereby displaying superior visible- light-driven photodegradation of CR in high concentration. This work may provide a green engineering heterojunction technology to develop the advanced multifunctional nanocomposites for their applications in wastewater purification.

The inefficiency of conventional photocatalytic treatment for removing rhodamine B is posing potential risks to ecological environments. Here, we construct a highly efficient photocatalyst consisting of Ag

Inferior electrical conductivity and large volume variation are two disadvantages of metal selenides. In this work, we have designed a core-shell structure of FeSe

The lithium-sulfur (Li-S) battery has been attracting much more attention in recent years due to its high theoretical capacity and low cost, although various issues, such as the “shuttle effect” and the low use ratio of active materials, have been hindering the development and application of Li-S batteries. The separator is an important part of Li-S batteries, and its modification is a simple and effective strategy to improve the electrochemical performance of Li-S batteries. In this work, we explore separators with different functions on their two sides that have been produced by a step-by-step electrospinning method. The multifunctional separator on one side is pure gelatin, and the other side is zeolitic imidazolate framework-67 (ZIF-67)-C60-gelatin. The ZIF-67-C60-gelatin layer on the cathode side is of great importance. The chemisorption sites on it are provided by ZIF-67, and the transformation sites of lithium polysulfide are provided by C60. Gelatin, which is on the anode side, as an admirable separator material, makes the lithium flux uniform and thus prevents the generation of lithium dendrites. This type of multifunctional nanofiber separator based on double gelatin layers plays an important role in the adsorption and conversion of polysulfides, and it improves the overall performance of the Li-S battery. As a result, the Li-S batteries assembled with the prepared separator can still maintain the capacity of 888 mAh g-1 after 100 cycles at 0.2 C, and the capacity retention rate of the Li-S batteries is 72.9% after 400 cycles at 2 C. This simple preparation method and high-performance bilayer membrane structure provide a new route for commercial application.

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.

Regular WO3 nanocubes have been prepared on a large scale through a convenient hydrothermal route at the temperature of 200 °C. The products were characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy, UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. A crystal growth process for WO3 nanocubes was simply proposed based on the comparative experiments. The band gap energy (Eg) was determined to be 2.58 eV based on the UV-vis DRS analysis, and the PL spectrum exhibited a strong blue light emission band centered at 469 nm. The as-prepared WO3 nanocubes showed higher visible light photocatalytic performance for degrading rhodamine B compared with WO3·H2O and WO3·0.33H2O/WO3 which were obtained at 80 °C and 140 °C, respectively, suggesting potential application in the region of wastewater purification.

Hierarchically porous NiO hollow architectures (HPHAs) were synthesized via a one-pot facile chemical bath deposition method and followed by a calcination process. The crystal structure, component and morphology of the products were characterized by various techniques. The results revealed that hierarchical architectures with hollow interior are composed of mesoporous NiO nanoflakes with thickness of about 8 nm. Interestingly, the as-synthesized NiO HPHAs have the unusual three-ordered porous features including a microscale hollow interior and two mesoscale pores which are attributed to the holes on the surface of nanoflakes with an average diameter of about 3.9 nm and the cavities on the wall of microsphere in the range of 20–40 nm in diameter formed by interconnecting nanoflakes. These comprehensive hierarchically porous structures are beneficial for the adsorption performance towards Congo red in water. The absorptive capacity over NiO HPHAs achieved about 1.8 and 4.0 times as high as that of the precursor β-Ni(OH)2 hollow microspheres (HSs) and the commercial activity carbon (AC) under the same conditions. The studies of adsorption kinetics illustrated that the adsorption behavior perfectly obeyed the pseudo-second-order model and the adsorption isotherm fits the Langmuir adsorption assumption well. The maximum adsorption capacities were calculated to be 490.2 mg g−1 according to the Langmuir equation, which is excellent result compared to NiO absorbents. The high-efficiency adsorption capacities for NiO HPHAs are attributed to the large specific surface area, the synergistic effect of micro-mesoporous structure and the electrostatic interaction of NiO with CR molecules. Additionally, NiO HPHAs can be easily renewed and has good chemical stability, indicating a great promising absorbent in the application for the removal of diazo organics in wastewater.

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.

Two types of hierarchical mesoporous CuS nanospheres, i.e., solid spheres (SSs) and hollow spheres (HSs), were controllably synthesized by a facile and green microwave-assisted wet chemical process, using copper acetate and thiourea aqueous solutions as precursors without a surfactant or template. The crystal structures, morphologies and photocatalytic properties of the products were characterized by various techniques. The results indicated that CuS SSs of 150 ± 50 nm in diameter are made of nanograins of about 10 nm in size, whereas CuS HSs of 400 ± 100 nm in outer-diameter are the assembly of ultrathin nanosheets in thickness of about 6 nm. The as-obtained both CuS architectures exhibit far superior dye degradation properties than commercial CuS powder for the decomposition of organic dyes including rhodamine B, methylene blue and malachite green with the help of hydrogen peroxide under visible light. Specially, using CuS HSs as catalyst, the decoloring rates of three organic dyes catalyst reach above 90% after just 1 min of irradiation and are approaching 100% after 20 min of irradiation, suggesting a fast and efficient photocatalytic activity and a promising application in industrial wastewater purification.

This work was supported by the Key Projects of Support Program for Outstanding Young Talents of Anhui Province (gxyqZD2016151), the Natural Science Foundation of Anhui Province (1808085MB40), the Program of Study Abroad for Excellent Young Scholar of Anhui Province (gxfxZD2016221), the Natural Science Foundation of Anhui Province Educational Committee (KJ2014ZD08, KJ2015A145), and the Special Foundation for Scientists of Hefei University (15CR06).

Heteroatom doping is considered to be an efficient strategy to improve the electrochemical performance of carbon-based anode materials for Na-ion batteries (SIBs), due to the introduction of an unbalanced electron atmosphere and increased electrochemical reactive sites of carbon. However, developing green and low-cost approaches to synthesize heteroatom dual-doped carbon with an appropriate porous structure, is still challenging. Here, N/S-co-doped porous carbon sheets, with a main pore size, in the range 1.8&ndash, 10 nm, has been fabricated through a simple thermal treatment method, using KOH-treated waste bagasse, as a carbon source, and thiourea, as the N and S precursor. The N/S-co-doped carbon sheet electrodes possess significant defects, high specific surface area, enhanced electronic conductivity, improved sodium storage capacity, and long-term cyclability, thereby delivering a high capacity of 223 mA h g&minus, 1 at 0.2 A g&minus, 1 after 500 cycles and retaining 155 mA h g&minus, 1 at 1 A g&minus, 1 for 2000 cycles. This work provides a low-cost route to fabricate high-performance dual-doped porous carbonaceous anode materials for SIBs.

The BiOCl/β-FeOOH composite was prepared using one-step glucose assisted hydrothermal method at 100 °C. The as-synthesized sample was characterized by X-ray diffraction, field emission scanning electron microscope, transmission electron microscope and UV–vis spectrophotometer. The photocatalytic performance of the composite was evaluated through photo-degradation of Rhodamine B (RhB) under visible light irradiation. It was found that the used glucose played a significant role in the combination of the BiOCl with β-FeOOH. The obtained composite exhibited much better photocatalytic activity in degradation of RhB than the pure BiOCl and β-FeOOH, which would be of great promise for the industrial application of this catalyst to oxidize organic pollutants for wastewater treatment. The enhanced photocatalytic performance can be attributed to the introduction of β-FeOOH nanorods which leads to the relative reduction of the band gap (E g ) of the composite, because of which electrons and holes are easily generated.

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).

Cubic-phase CdSe (C–CdSe) hollow microspheres and hexagonal-phase CdSe (H–CdSe) urchin-like microstructures have been controllably synthesized through an effective mixed solvothermal method in the absence of any surfactants. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV–Vis absorption spectroscopy and photoluminescence spectroscopy. The volume ratio of ethylenediamine and ethanol of two solvents is a key factor that determines the phase and shape of CdSe crystals. When the volume ratio of ethylenediamine and ethanol is changed from 1:3, through 1:1 to 4:1, CdSe crystals can be changed from hollow spheres (cubic phase), through acanthosphere (mixed phase) to urchin-like architectures (hexagonal phase). Based on the investigation of the influence of solvent ratio on the phase and morphology of CdSe, an “in situ phase transformation and crystal growth” mechanism is proposed. Optical properties indicate that the as-obtained H–CdSe urchin-like microstructures have much stronger optical absorption and emission than C–CdSe hollow microspheres.

Metastable h-MoO3 hexagonal prisms have been fabricated through a simple green ultrasonic-assisted chemical route. After calcination at 440 °C for 2 h, the thermodynamically stable α-MoO3 nanoplate-based rods have been achieved through a process of in situ phase transformation. The as-synthesised products have been characterised by powder X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectrum, UV–vis diffuse reflection spectroscopy and photoluminescence spectroscopy. The phase transformation from metastable h-MoO3 to stable α-MoO3 is observed at 419 °C according to the differential scanning calorimetry results. The possible growth mechanism of MoO3 crystals has been proposed based on the experimental results. The prepared two kinds of MoO3 samples both display higher photocatalytic performance for degrading rhodamine B compared to that of commercial MoO3. In the present system, α-MoO3 nanoplate-based rods exhibit slightly higher degradation activity than h-MoO3...

Well dispersed NiO architectures with in-built nanostructure were successfully achieved via a green microwave-assisted aqueous chemical reaction followed by a calcination process. The as-prepared products were characterized by XRD, FESEM, TEM, HRTEM, and N 2 adsorption/desorption isotherms. The results indicated that the three-dimensional (3D) flower-like microspheres with 400–600 nm in diameter are assembled by the pure cubic NiO nanosheets with the thickness of about 10 nm. It should be noted that the interconnecting ultrathin nanosheets have intercrystal mesoporosity and the inhomogeneous multimodal mesopores are ranging from 2.3 to 30.4 nm. A formation mechanism for NiO architectures was simply proposed. In addition, for dye removal in water, the as-obtained NiO as adsorbent exhibited a fast and high adsorption behavior for Congo red (CR), suggesting a promising application in water treatment.

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.

Hierarchical MoO 2 hollow microspheres have been successfully fabricated on a large scale through a convenient hydrothermal reductive process. MoO 2 hollow microspheres are composed of subunits (nanospheres or nanoplates), which are actually self-aggregated by hundreds of tiny primary nanoparticles. BET nitrogen adsorption reveals that the MoO 2 hollow microspheres have mesoporous shell with pore size of 5–20 nm. Reaction parameters, such as mole ratio of reactant, reaction temperature and time, were discussed in detail. Center-hollowing evolution process induced by Ostwald ripening was proposed to explain the formation mechanism of hierarchical MoO 2 hollow microspheres. The adsorption ability of MoO 2 hollow microspheres was evaluated by adsorbing Cr (VI) at room temperature. The experimental results indicated that MoO 2 absorbent displayed higher adsorption capacity compared to activated carbon, which would be potential application in wastewater treatment.

Hierarchical WO 3 nanocakes have been prepared by a green ultrasound-assisted solution chemical route and subsequent heating treatment process. The products have been characterized by XRD, FESEM, TEM, HRTEM, UV–vis diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. The results reveal that the as-synthesized cake-like architectures are assembled by multi-layered monoclinic WO 3 nanosheets with the thickness of 20–30 nm. The band gap energies are estimated to be 2.65 eV. PL spectra shows a strong green-light emission band centered around 528 nm. A formation mechanism for WO 3 nanostructures is simply proposed. More importantly, the cake-like WO 3 architectures exhibit the superior photocatalytic activity according to the photodegradation of methylene blue under visible lighting.

Uniform hierarchical Cu 2 O hollow submicrospheres have been successfully prepared via a facile sonochemical process at room temperature. The products were examined by XRD, FESEM, TEM, HRTEM, N 2 adsorption/desorption isotherms and UV–vis diffuse reflectance spectra (DRS). It was found that the hierarchical Cu 2 O hollow spheres with 400–600 nm in outer diameters are assembled by pure cubic Cu 2 O nanoparticles. The band gap energies were estimated to be 1.93 eV. The pore size distribution displayed inhomogeneous mesopores with size ranging from 2 to 15 nm. A possible growth mechanism for the hierarchical hollow Cu 2 O structures was simply proposed. More importantly, the adsorption capacities of as-prepared Cu 2 O hollow spheres for methyl orange were calculated to be 446.43 mg g −1 , suggesting a promising application for wastewater purification.

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.

Two dimensional (2D) self-supporting lead sulfide (PbS) arrays composed of ordered quadrangular nanopyramids were successfully fabricated through a convenient wet-chemical route at room temperature. The as-synthesized products were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, UV–vis–NIR absorption and photoluminescence spectroscopy. The as-prepared highly ordered self-supporting superstructures are stable under ultrasonic conditions. A “template-mediated in situ growth” mechanism is proposed for the formation of 2D PbS superstructures. With the prolongation of reaction time, the morphology evolution of PbS is clearly observed, which could be changed from nanopyramid-aggregated arrays into nanocube-aggregated arrays at original position. The optical properties of PbS self-supporting superstructures are investigated in detail.

Three kinds of CdS nanostructures, that is, hexagonal nanospheres (CdS-1), hierarchical caterpillar-fungus-like hexagonal nanorods (CdS-2) and hierarchical cubic microspheres (CdS-3), were controllably synthesized by a facile and one-pot microwave-assisted aqueous chemical method using ethanediamine as a phase and morphology controlling reagent. The as-prepared products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. The results show that CdS-1 is mainly composed of monodispersed hexagonal nanospheres with average diameters of about 100 nm; hexagonal CdS-2 has lengths in the range of 600–800 nm and diameters of 40–60 nm, assembled by nanoparticles about 20 nm in diameter; and CdS-3 is pure cubic microspheres with diameters in the range of 0.8–1.3 μm, aggregated by tiny nanograins with size of 5.8 nm. The band gap energies of CdS products were calculated to be 2.30, 2.31 and 2.24 eV observed from UV–vis DRS for CdS-1, CdS-2 and CdS-3, respectively. PL spectra of CdS samples showed that sphalerite CdS-3 possesses a very weak fluorescence, while wurtzite CdS-2 has a strongest green near-band edge emission (NBE) at 550 nm. The visible light photodegradation of methylene blue and rhodamine B in the presence of CdS photocatalysts illustrates that all of them display high photocatalytic activities. Significantly, the cubic CdS-3 exhibits more excellent photocatalytic behavior in degradation of organic dyes than the other hexagonal CdS, which is closely related to the phase and morphology structure of cubic CdS.

Novel hierarchical Bi 19 S 27 Br 3 superstructures have been synthesized on a large scale by a facile and green microwave-assisted aqueous chemical process for the first time. The products have been characterized by XRD, FESEM, TEM, HRTEM, SAED and UV–vis diffuse reflectance spectrum (DRS). The results reveal that the self-supported fabric-like Bi 19 S 27 Br 3 superstructures possess a hexagonal phase with diameters of 4–5 μm, constructed by cross-bedded nanofibers with average diameters of about 80 nm. Further, the nanofibers are aggregated by ultrafine nanosilks containing stacking faults. The UV–vis DRS shows that the Bi 19 S 27 Br 3 superstructures have significant absorption in the visible region, from which the band gap energy is calculated to be 1.42 eV. According to the photodegradation of Rhodamine B under visible lighting, the Bi 19 S 27 Br 3 superstructures display high efficient catalytic performance. This work may reignite the intensive study of the higher-order sulfohalogenides.

Novel hollow BiOBr eggshells with inorganic fullerene-like structure have been successfully fabricated on a large scale via a facile ultrasound-assisted anion exchange reaction and subsequent heating treatment process. The products have been characterized by FESEM, TEM, HRTEM, XRD and N 2 adsorption/desorption isotherms. The results reveal that the hollow eggshells possess a pure tetragonal phase BiOBr, with the average thickness of about 12 nm, opening diameters of 500–800 nm and depths of 400–600 nm. The walls of eggshells, owning inorganic fullerene-like layered structure, are constructed by nanograins with size of about 10 nm. The average pore diameter of intercrystal mesopore is 2.8 nm and the specific surface is measured to be 36.56 m 2 g −1 . A possible formation mechanism for BiOBr hollow eggshells is proposed. According to the photodegradation of Rhodamine B under visible light irradiation, the hollow BiOBr eggshells exhibit excellent photocatalytic activity.

A series of hydroxyapatite (HAp)/poly(methyl mathacrylate) (PMMA) nanocomposites were prepared by free radical copolymerization of surface-modified HAp with methyl mathacrylate (MMA) via a bulk copolymerization process. Fourier transform infrared spectrophotometry and X-ray diffraction were employed to characterize the structures of the HAp/PMMA nanocomposites. Scanning electron microscope images showed that the as-prepared composite films were smooth, and no severe aggregation of HAp was observed when HAp content was 20 wt%) weakened the thermal and mechanical properties of the nanocomposites owing to the phase separation in the composite matrix caused by the strong aggregation of HAp particles.

Novel and uniform one-dimensional (1D) tadpole-shaped Cu nanostructures with single-crystal nature have been successfully fabricated on a large scale by using a convenient microwave-assisted chemical reductive process in the absence of any surfactants. The as-synthesized products are characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electronic diffraction (SAED) and UV–visible spectroscopy. FESEM and TEM images indicate that the prepared Cu nanotadpoles have hexagonal plate-like heads with edge size of 600–800 nm and 4–6 μm long wire-like tails with the middle part diameters of 100–200 nm. The purity and morphology of Cu crystals are greatly affected by the concentration of hexamethylenetetramine and ascorbic acid, which are realized by carefully controlling the experimental conditions. The possible mechanism for the formation of tadpole-shaped Cu nanostructures is discussed.