Shuxue Zhou

Porous nickel hydroxide-manganese dioxide-reduced graphene oxide ternary hybrid spheres as excellent supercapacitor electrode materials.

This paper reports the first nickel hydroxide-manganese dioxide-reduced graphene oxide (Ni(OH)2-MnO2-RGO) ternary hybrid sphere powders as supercapacitor electrode materials. Due to the abundant porous nanostructure, relatively high specific surface area, well-defined spherical morphology, and the synergetic effect of Ni(OH)2, MnO2, and RGO, the electrodes with the as-obtained Ni(OH)2-MnO2-RGO ternary hybrid spheres as active materials exhibited significantly enhanced specific capacitance (1985 F·g(-1)) and energy density (54.0 Wh·kg(-1)), based on the total mass of active materials. In addition, the Ni(OH)2-MnO2-RGO hybrid spheres-based asymmetric supercapacitor also showed satisfying energy density and electrochemical cycling stability.

Facile Synthesis of Superparamagnetic Fluorescent Fe3O4/ZnS Hollow Nanospheres

A very simple strategy for the synthesis of superparamagnetic and fluorescent Fe(3)O(4)/ZnS hollow nanospheres is presented. These hollow nanospheres are not only nontoxic with a highly porous shell and have diameters of <100 nm but also exhibit very good magnetic resonance and fluorescence.

Reduced graphene Oxide–MnO2 hollow sphere hybrid nanostructures as high-performance electrochemical capacitors

This paper presents the first successful fabrication of reduced graphene oxide (RGO)–MnO2 hollow sphere (HS) hybrid electrode materials through a solution-based ultrasonic co-assembly method. The porous structure of these MnO2 hollow spheres and the excellent dispersion of active materials give the as-fabricated RGO–MnO2 HS hybrid electrodes excellent specific capacitance and energy density, which can reach up to 578 F g−1 and 69.8 W h kg−1, respectively. These values are considerably larger than those of most reported graphene–MnO2 based hybrid electrochemical capacitors. This solution-processed method can also be used for the hybridization of graphene with other metal oxides in the fabrication of high-performance electrochemical capacitors.

Recent Advances in Applications and Performance of Inorganic Hollow Spheres in Devices

Inorganic hollow spheres have wide, important applications due to their unique structure, controllable morphology, and composition. Recent developments in the application and performance of inorganic hollow spheres in solar cells, UV photodectors, gas sensors, and supercapacitors are discussed. For each inorganic hollow sphere based device, a critical comment is given based on knowledge and related research experience. Some perspectives on the future research and development of these inorganic-hollow-sphere devices are given.

A facile and large-area fabrication method of superhydrophobic self-cleaning fluorinated polysiloxane/TiO2 nanocomposite coatings with long-term durability

A long-term superhydrophobic self-cleaning coating was first fabricated by simply blending ambient-cured fluorinated polysiloxane binder with TiO2 nanoparticles. The obtained coating has excellent durability in various environments, and this method can be used for large-scale fabrication of self-cleaning coatings for practical applications.

Self-Healing Underwater Superoleophobic and Antibiofouling Coatings Based on the Assembly of Hierarchical Microgel Spheres.

Marine biofouling has been plaguing people for thousands of years. While various strategies have been developed for antifouling (including superoleophobic) coatings, none of these exhibits self-healing properties because the bestowal of a zoetic self-repairing function to lifeless artificial water/solid interfacial materials is usually confronted with tremendous challenges. Here, we present a self-repairing underwater superoleophobic and antibiofouling coating through the self-assembly of hydrophilic polymeric chain modified hierarchical microgel spheres. The obtained surface material not only has excellent underwater superoleophobicity but also has very good subaqueous antibiofouling properties. More importantly, this surface material can recover the oil- and biofouling-resistant properties once its surface is mechanically damaged, similar to the skins of some marine organisms such as sharks or whales. This approach is feasible and easily mass-produced and could open a pathway and possibility for the fabrication of other self-healing functional water/solid interfacial materials.

Synthesis and Characterization of Poly(N-isopropylacrylamide)/Silica Composite Microspheres via Inverse Pickering Suspension Polymerization

In this paper, stable poly (N-isopropylacrylamide)/silica composite microspheres are successfully synthesized via inverse Pickering suspension polymerization using various sizes of silica particles as stabilizers. The droplets of N-isopropylacrylamide aqueous solution were first dispersed in toluene and stabilized by silica particles, and then polymerized to obtain poly (N-isopropylacrylamide)/silica composite microspheres. Preliminary studies show that these PNIPAm/silica composite microspheres have similar thermal-responsive behavior as pure microgels with the LCST of 32 degrees C. The releasing property of the composite microspheres can be either controlled by the particle size of the silica or the temperature.

Dispersion and functionalization of nonaqueous synthesized zirconia nanocrystals via attachment of silane coupling agents.

Zirconia (ZrO 2) nanocrystals, synthesized from zirconium(IV) isopropoxide isopropanol complex and benzyl alcohol, were dispersed and functionalized in organic solvents using three kinds of bifunctional silane coupling agents (SCAs), 3-glycidoxypropyltrimethoxysilane (GPTMS), 3-aminopropyltriethoxysilane (APTES), and 3-isocyanatopropyltriethoxysilane (IPTES). Completely transparent ZrO 2 dispersions were achieved in tetrahydrofuran (THF) with all three SCAs, in pyridine and toluene with APTES and IPTES, and in N, N-dimethylformamide with IPTES. Dynamic laser scattering (DLS) measurements and high-resolution transmission electron microscopical (HRTEM) observation indicated that the ZrO 2 nanocrystals are dispersed on a primary particle size level. Fourier transform infrared spectroscopy, solid-state (13)C- and (29)Si NMR spectroscopy, and thermogravimetric analysis demonstrated that all three SCAs are chemically attached to the surface of the ZrO 2 nanoparticles, however, in different bonding modes. Except for GPTMS/ZrO 2/THF dispersion and IPTES/ZrO 2/pyridine dispersion, all other transparent dispersions have poor long-term stability. The increasing polarity, due to high amount of APTES attached and high hydrolysis and condensation degree of the bonded APTES, and the aggregation, due to interparticle coupling via the bonded triethoxysilyl group, are the causes of the poor long-term stability for the ZrO 2 dispersions with APTES and IPTES, respectively. Nevertheless, the APTES-functionalized ZrO 2 precipitates can be deagglomerated in water to get a stable and transparent aqueous ZrO 2 dispersion via addition of a little hydrochloric acid.

Fabrication of hollow silica spheres using droplet templates derived from a miniemulsion technique

Hollow silica spheres have been successfully fabricated by means of a miniemulsion technique, in which miniemulsion droplets of tetraethoxysilane (TEOS) and octane were prepared with cetyltrimethylammonium bromide as a surfactant and hexadecane as a costabilizer and used as templates. As the TEOS diffused out from the droplets, it was hydrolyzed and condensed to form a silica shell at the oil/water interface. In this way, hollow silica spheres could be obtained directly since the miniemulsion droplets of octane could be evaporated very easily during the reaction process or the drying process; neither an additional dissolution nor a calcination process or additional surface modification of the templates were needed.

Study on the morphology and tribological properties of acrylic based polyurethane/fumed silica composite coatings

Two fumed silica (one hydrophilic and one hydrophobic) were used in the high solid acrylic based polyurethane coatings by directly mixing. The dispersion of fumed silica particles in the bulk of polyurethane coats was characterized by transmission electron microscope (TEM) and surface morphology examined using a scanning probe microscope (SPM). Micro indentation and scratching tests were carried out with a nano-indenter. Both hydrophilic and hydrophobic fumed silica nearly have the same dispersion in acrylic based polyurethane coats. The surface roughness of polyurethane coats increases as fumed silica increases, however, the surfaces of polyurethane coatings containing hydrophobic fumed silica are rougher than that containing hydrophilic fumed silica at the same content. Addition of fumed silica can obviously enhance the micro indentation hardness (MIH) and elastic modulus of polyurethane coats and the higher the content of fumed silica is, the higher the MIH is for hydrophilic one but for hydrophobic one only under normal load less than 20 mN. In the micro scratch experiment, the elastic response and plastic deformation nearly keep constant with normal force increasing for pure acrylic based polyurethane coats. But the percentage of elastic response decreases and the percentage of plastic deformation increases as normal force increases for the polyurethane coats with fumed silica. Crack occurs when scratching under normal force higher than 50 mN for the polyurethane coats with fumed silica, and as the content of fumed silica increases, the critical force for crack increases. Additionally, both hydrophilic and hydrophobic fumed silica have no obvious influence on the response to marring stress and micro mar resistance (MMR) of acrylic based polyurethane.