Search

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).

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.

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.

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.

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.

Hierarchical cocoon shaped CuO hollow nanostructures have been synthesized on a large scale by a facile green microwave-assisted aqueous process at reflux in the absence of templates and additives. The as-prepared products were investigated by FESEM, TEM, HRTEM, XRD and UV–vis absorption optical properties. The results reveal that cocoon shaped structures, that is ellipsoids, possess a monoclinc phase CuO with the long and short diameters of about 300 nm and 150–200 nm, respectively. The walls of hollow cocoons with around 50 nm in thickness are self-assembled by nanorods with diameters of 6–8 nm. A possible mechanism for the hollow CuO structures was proposed, in which CO 2 bubbles act as soft-template to aggregate the primary monomers. The band gap energies were estimated to be 2.03 eV, which showed the quantum size effect of the nanosized semiconductors.

By using a solvothermal reaction in mixed solvent of ethylenediamine and ethylene glycol, nanoparticle-assembled sheet-like CuInSe 2 with hierarchically mesoporous structures were successfully fabricated with the absence of any template or structure-directing agent. The as-synthesized products were characterized by XRD, EDX, FESEM, TEM, HRTEM, BET nitrogen adsorption and NIR absorption spectrum. The possible formation mechanism was simply discussed. The size of mesopores is hierarchically distributed in the range of 2–30 nm and the specific surface area was estimated to be 10.15 m 2 /g. The value of band gap (E g ) was calculated to be 1.00 eV based on its NIR absorption spectrum.

ZnO hollow spherical structures have been synthesized by a facile template-free sonochemical process. The structures and morphologies of products have been characterized by XRD, FESEM and TEM. The results reveal that hollow spherical structures possess a hexagonal wurtzite structure with the in- and out-diameters of about 400 and 500 nm, respectively. The walls of the hollow structures are self-assembled by nanoparticles, partly composed of hexagonal nanoflakes with 40 nm in side lengths. Room temperature photoluminescence (PL) spectrum showed a UV emission at ∼ 384 nm and a broad green emission at the center of 535 nm. A possible formation mechanism was also proposed.

Porous magnetite (Fe 3 O 4 ) microspheres can be direct acquired by hydrothermal reaction of Fe-citrate complex (Fe (NH 4 ) 2 H (C 6 H 5 O 7 ) 2 ) in neutral solution. Results show that the obtained Fe 3 O 4 particles are nearly spherical in shape and about 2 μm to 3 μm in mean diameter. Every magnetite microsphere is made of many ultrafine Fe 3 O 4 nanoparticles and porous in structure. The as-prepared porous magnetite microspheres have higher surface area (~ 83 m 2 /g) and excellent magnetic properties (M s = 81 emu/g, H c = 145 Oe) at room temperature.