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We facilely fabricate hierarchical 3D microspheres consisting of 2D V 2 O 5 (vanadium pentoxide) nanosheets by a low temperature hydrothermal method and use it to structure hierarchical 3D micro-/nano-LIBs (lithium ion batteries) cathode. This is a template-free and facile method easy for scale-up production of hierarchical 3D micro-/nano-structured V 2 O 5 spheres beneficial for high performance LIBs applications. Such a facile method resulted hierarchical 3D micro-/nano-V 2 O 5 possess many unique features good for LIBs: (1) 2D V 2 O 5 nanosheets facilitate the Li + diffusions and electron transports; (2) hierarchical 3D micro-/nano-cathode structure built up by V 2 O 5 nanosheet spheres will lead to the close and sufficient contact between electrolytes and activate materials and at the same time will create buffer volume to accommodate the volume change during discharging/charging process; and (3) micro-scale V 2 O 5 spheres are easy to result in high cell packing density beneficial for high power battery. As revealed by the experimental results, the micro-/nano-V 2 O 5 electrode demonstrates high initial discharge and charge capacities with no irreversible loss, high rate capacities at different currents and long-lasting lifespan. The high-energy and high-power performances of the micro-/nano-V 2 O 5 electrode is ascribed to the unique hierarchical micro-/nano-structure merits of V 2 O 5 spheres as abovementioned. In view of the advantages of facile fabrication method and unique features of 3D micro-/nano-V 2 O 5 spheres for high power and high energy LIB battery, it is of great significance to beneficially broaden the applications of high-energy and high-power LIBs with creating novel hierarchical micro-/nano-structured V 2 O 5 cathode materials. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical 3D dendritic TiO2 nanospheres building with ultralong 1D TiO2 nanoribbon/wires were hydrothermally synthesized via controlling the hydrolysis rate of precursor by EG. It is found that the EG and Cl− in the precursor solution are the dominant factors in controlling the hydrolysis rate of Ti4+ from TTIP, and the growing direction of 1D TiO2, respectively. Through optimizing the molar ratio of TTIP:EG, hierarchical 3D dendritic TiO2 nanospheres building with long 1D nanoribbons (TiO2 nanoribbon spheres) were synthesized at a molar ratio of TTIP:EG = 1:2. And hierarchical 3D dendritic TiO2 nanospheres building with even longer and thinner 1D TiO2 nanowires (TiO2 nanowire spheres) were synthesized via further reducing the hydrolysis rate of Ti4+ by increasing the content of EG at a molar ratio of TTIP:EG = 1:3. The hierarchical 3D dendritic TiO2 nanoribbon/wire spheres were well characterized by a variety of techniques such as FESEM, TEM, XRD, N2 adsorption/desorption, UV–vis spectra, etc. A “win–win” strategy was developed to integrate the hierarchical TiO2 nanoribbon/wire spheres and membrane for high performance photocatalytic membrane water purification through maximizing the advantages of TiO2 photocatalysis and membrane, while minimizing their disadvantages. Hierarchical TiO2 nanoribbon/wire spheres exhibited high performance for water purification in terms of high flux, low fouling, high removal rate of pollutants, and long lifespan of membrane, both in concurrent dead end and cross flow membrane system. The rationale behind this phenomenon lies in that the hierarchical TiO2 nanoribbon/wire spheres in the concurrent system possess the advantages of mitigating the membrane fouling via photocatalytic degrading the organic pollutants relying on their high photocatalytic activities; and keeping high water flux owing to the porous functional layer favorable for water pass through. The experimental results demonstrated that the hierarchical TiO2 nanoribbon/wire spheres have better photodegradation ability of AO 7 and RhB pollutants so as to result in higher ability in mitigating fouling, and keep higher flux than TiO2 P25 under the same conditions. It is believable that this study is of great significances both in synthesizing hierarchical 3D dendritic TiO2 nanospheres building with ultralong 1D nanoribbon/wires, and in providing a “win–win” strategy for high performance concurrent photocatalytic membrane water purification featured as high flux, high removal rate of pollutants, low fouling and long membrane lifespan. [Copyright &y& Elsevier]

Abstract: A general method for the fabrication of flexible, multifunctional and hierarchically-nanostructured membranes was reported. As an example, the as-prepared TiO2 nanorod self-supporting membrane shows excellent advantages, when it is used in concurrent filtration and degradation of the pollutants in waters, including high mechanical flexibility, high permeate flux, high photocatalytic activity and no membrane fouling problem, which indicate its great potential for sustainable environmental applications. And this general method also was successfully demonstrated with a ZnO nanoflake self-supporting membrane, which also have great potential in environmental and energy applications. [Copyright &y& Elsevier]

Abstract: The effect of fabrication method on the properties of hierarchical 3D TiO2 nanostructures was investigated by employing and developing both hydrothermal method and calcination method to synthesize hierarchical 3D TiO2 nanorod spheres in this study. A comprehensive comparison in terms of morphologies, crystallization, specific surface areas, light absorption capabilities, and photoluminescence spectrum was conducted between 3D TiO2 nanorod spheres synthesized via hydrothermal method and that synthesized via calcination method. A better photocatalytic activity was demonstrated over the TiO2 nanorod spheres synthesized through calcination method. This was ascribed to the better crystallization and monodispersion of the hierarchical 3D TiO2 nanorod spheres resulted from the calcination method; thus rendering it with more superior characteristics such as larger specific surface area, enhanced light absorption capability and faster transfer of electrons which suppress the recombination of photogenerated electrons and holes. This study is thus significant not only in promoting the development of hierarchical 3D TiO2 nanorod spheres via different methods, but also in revealing the effect of fabrication method on the photocatalytic activity of hierarchical 3D TiO2 nanorod spheres. The calcination method is proposed to be a facile and promising method for scale-up production of the hierarchical 3D TiO2 nanorod spheres with high photocatalytic activity for efficient pollutants degradation. [Copyright &y& Elsevier]

Abstract: A novel photocatalyst was designed from the inspiration of natural forest''s high efficient on light harvesting and energy conversion. This novel “forest-like” photocatalyst was successfully synthesized by a facile continuously-conducted three steps methods: electrospinning TiO2 nanofiber acts as the trunks, hydrothermal growth ZnO nanorods on the surface of TiO2 nanofiber acts as the branches, while photodeposition of Cu nanoparticles on the surface of TiO2 nanofiber and ZnO nanorods act as the leaves. This novel photocatalyst demonstrated higher photocatalytic hydrogen generation rate than most of semiconductor catalysts and many newly developed catalysts such as Pt/TiO2 catalyst and artificial leaves Pt/N–TiO2 catalyst in a water/methanol sacrificial reagent system under the light irradiation as a result of its enhanced light absorption ability, enlarged specific surface area promoting mass transfer and providing more reaction sites and its potential on anti-recombination of electrons and holes. Meanwhile, it is interesting to note that the photocatalytic hydrogen generation activity has a liner relationship with the hierarchy of materials, which means higher hierarchy materials display higher photocatalytic hydrogen generation activity. It is reasonable to believe that this natural mimic photocatalyst without noble metals will benefit the energy generation and novel materials development. [Copyright &y& Elsevier]

Abstract: To counter the global water crisis such as water resources scarcity and water quality deterioration, membrane filtration has been widely used as a promising technology. Recently, nano-materials and its structured membranes demonstrated multifunctional water purification capability in terms of decontamination and disinfection. Here, hierarchical nitrogen (N)-doped “nut-like” ZnO nanostructured material was hydrothermally synthesized at large scale. This hierarchical N-doped “nut-like” ZnO nanostructured material was well characterized and successfully assembled on a piece of polymer membrane surface to create a multifunctional membrane. This newly developed membrane demonstrated high pollutants removal ability via rejection and photodegradation, and strong antibacterial growth ability under visible light irradiation. At the same time, this novel membrane holds the potential to produce clean water at a constant high flux. The experimental results indicated that the hierarchical N-doped ZnO “nut-like” nanostructured material enhanced the photocatalytic activity in a comparison to commercial ZnO powder. This is caused by enlarging the specific surface area and enhancing the light utilization rate. It is reasonable to believe this hierarchical N-doped “nut-like” ZnO nanostructured membrane would benefit the water purification field. [Copyright &y& Elsevier]

Abstract: Through hydrothermally growing SrTiO3 cubics on the surface of electrospun TiO2 nanofibers, SrTiO3/TiO2 nanofibers heterostructures were successfully fabricated in the present study. This process is able to ensure uniform distribution of SrTiO3 on the surface of TiO2 nanofibers and lead to close contact between SrTiO3 and TiO2, which is beneficial for the fast separation of photogenerated electrons and holes so as to suppress the recombination of photogenerated electrons and holes at the interphase of SrTiO3 and TiO2. Besides this, the long 1D fibrous structure easy for electron transfer, the hierarchical structure promoting mass transfer and allowing more light reflection and absorption, and the large specific surface area providing more reactions sites to facilitate the reactants to desired oxidation places all together create a synergistic effect on improving the photocatalytic activity of the hierarchical SrTiO3/TiO2 nanofibers heterostructures. Under the irradiation of UV light, in a water/methanol sacrificial reagent system, the SrTiO3/TiO2 nanofibers heterostructures generate five times more H2 than bare TiO2 nanofibers because of its high photocatalytic activity. [Copyright &y& Elsevier]

Abstract: Currently, the biggest challenge for filtration membrane application is the severe membrane fouling problem, which consequently results in low flux and high energy cost. Herein, a novel kind of multifunctional membrane was fabricated via integrating the advantages of conventional polymer membrane as supporting layer and “forest” like hierarchically structured TiO2/ZnO nanomaterials as functional layer. This membrane has shown multifunctional properties, such as, high photocatalytic activity, high flux and high antibacterial capacity, which make it as a good candidate to tackle the challenge of producing clean water at a constant high flux with no membrane fouling problem and energy saving manner. The outstanding performance of this novel membrane would bring enough benefits to filtration membrane industry for clean water production and environmental protection. [Copyright &y& Elsevier]

Abstract: Novel high efficient photocatalyst is the key for photocatalytic hydrogen generation from water splitting. In this study, a novel hierarchical CuO/ZnO “corn-like” architecture was designed and synthesized via a combination of hydrothermal and photodeposition method. The as-prepared nanostructured materials was shown to effectively generate hydrogen in the mixture of methanol and water (v/v = 1:10). This is because the hierarchical CuO/ZnO “corn-like” architecture: 1) greatly enhances the light utilization rate due to its special architecture, 2) enlarges the specific surface area, providing more reaction sites and promoting mass transfer, 3) promotes the photogenerated electrons transfer from ZnO to CuO, achieving the anti-recombination effect of electrons and holes, and 4) avoids the photocorrosion of ZnO to improve the stability of ZnO as a catalyst during water splitting. Moreover, the novel hierarchical CuO/ZnO “corn-like” architecture is easily recovered for reuse. [Copyright &y& Elsevier]