A set of identical Co3O4 nanosheets with different oxygen vacancy amounts are rationally designed by varied reduction treatments and comparison of their properties. Remarkably, the oxygen-vacancy-rich Co3O4 nanosheets (OVR-Co3O4 NSs) exhibit excellent electrochemical performance for their potential use as a promising candidate for the next generation of supercapacitors.

TiO2@carbon with a nanosheet morphology and core–shell structure was constructed by self-assembly/carbonization of P123, CTAB and exfoliated titanate nanosheets. The obtained composite possesses an ultrathin structure (∼5.5 nm) and exhibits high capacity (549 mA h g−1) and excellent cyclability (385 mA h g−1 after 2000 cycles at 4.6 A g−1) as an anode for Li-ion batteries.

Synthesis of functionalized mesoporous carbon by an easy-accessed method is of great importance towards its practical applications. Herein, an evaporation induced self-assembly/carbonization (EISAC) method was developed and applied to the synthesis of sulfonic acid group functionalized mesoporous carbon (SMC). The final mesoporous carbon obtained by EISAC method possesses wormlike mesoporous structure, uniform pore size (3.6 nm), large surface area of 735 m2/g, graphitic pore walls and rich sulfonic acid group. Moreover, the resultant mesoporous carbon achieves a superior electrochemical capacitive performances (216 F/g) to phenolic resin derived mesoporous carbon (OMC, 152 F/g) and commercial activated carbon (AC, 119 F/g).Download high-res image (153KB)Download full-size imageHerein, an evaporation induced self-assembly/carbonization (EISAC) method was developed and applied to the synthesis of sulfonated mesoporous carbon (SMC). The final mesoporous carbon obtained by EISAC method possesses wormlike mesoporous structure, uniform pore size, large surface area (735 m2/g), graphitic pore walls and rich sulfonic acid group. Moreover, the resultant mesoporous carbon achieves a superior electrochemical capacitive performances (216 F/g) to phenolic resin derived mesoporous carbon (OMC, 152 F/g) and commercial activated carbon (AC, 119 F/g).

The development of sustainable routes for the synthesis of noble metal supported catalysts is of high importance because of their wide applications on a large scale in the catalysis field. Herein we report a facile solvent-free solid-state dispersion route to fabricate highly dispersed ultrafine palladium nanoparticle supported catalysts. In the first step, a noble metal precursor Pd(acac)2 was dispersed spontaneously by treating the physical mixture of Pd(acac)2 and catalyst support hydroxyapatite (HAP) at 120 °C under a flow of N2. Subsequent H2 reduction results in the formation of two kinds of Pd particles. In situ reduction at 120 °C is essential for preparing highly dispersed Pd nanoparticles (∼1.2 nm, a1Pd/HAP-SSD) and cooling-down reduction leads to the formation of larger Pd nanoparticles (∼4 nm, b1Pd/HAP-SSD). The as-prepared a1Pd/HAP-SSD exhibits higher activity for phenol hydrogenation than b1Pd/HAP-SSD and that obtained by a traditional wet impregnation method, due to the highly dispersed ultrafine Pd0 nanoparticles obtained by in situ dispersion/reduction. Compared with conventional wet chemistry-based methods, the synthesis route in this work simplifies the synthesis process, avoids producing large polluted wastes, and enhances the dispersion of noble metals. This may open a new way to prepare highly dispersed/active noble metal supported catalysts and is also potentially of high importance for the green production of noble metal supported catalysts on a large scale in the future.

•Mesoporous carbons were synthesized from phenol with the aid of catalytic hydroxylation.•The obtained mesoporous carbon possesses pseudocapacitive oxygen group.•The final mesoporous carbon presents superior supercapacitive performances.As an important route towards the preparation of ordered mesoporous carbon (OMC), the aqueous assembly method with phenol as precursor still faces a challenge of yielding an OMC under acidic conditions because of the formation of thermoplastic resin in acidic conditions, which leads to structure collapse during carbonization. Herein, we developed an approach combined catalytic hydroxylation of phenol with assembly process to prepare OMC under acidic conditions. In our route, phenol was first partially converted into highly reactive phenols (catechol and hydroquinone) by catalytic hydroxylation, and the resulted mixture of phenols then interacted with template of Pluronic block copolymer F127 under acidic conditions to form a thermosetting mesophase through phase separation, which was carbonized to form OMC. The obtained carbon possesses ordered mesostructure with surface area of 435 m2/g, pore volume of 0.41 cm3/g and achieves high capacitance of 231 F/g for supercapacitor compared to that of normal mesoporous carbon (151 F/g) and activated carbon (AC, 119 F/g), which may be attributed to its high oxygen content resulted from catalytic hydroxylation. The developed strategy not only affords a novel approach for the synthesis of OMC but also provides a way to introduce pseudocapacitive oxygen on ordered mesoporous carbon.

Anatase-type titania with ultrathin nanosheet morphology and sintering-resistant structure was constructed from monolayer titanate nanosheets isolated by uniform silica nanoparticles. The obtained anatase titania nanosheets possess high accessible surface area, ultrathin thickness (∼0.6 nm), dominant (116) facets exposed, wide bandgap and exhibits excellent photocatalytic activity.

Crystalline mesoporous γ-Fe2O3 with a high surface area was prepared by a novel solvent-free route. This material exhibits a high reversible capacity with superior cycle performance and an exceptional high-rate capability as an anode material for Li-ion batteries.

•Rhombus-shaped mesoporous ZnAl2O4 (Meso-ZA) nanocrystal was fabricated.•The obtained Meso-ZA possesses high thermal stability and rich Lewis acid sites.•The Meso-ZA exhibits a superior catalytic performances on phenol hydroxylation.Mesoporous zinc aluminate (ZnAl2O4) nanocrystal with rhombus-shaped morphology was for the first time synthesized by a vacuum-promoted self-assembly and alkaline hydrothermal approach. The obtained mesoporous ZnAl2O4 (Meso-ZA) was characterized by X-ray diffraction (XRD), nitrogen sorption, transmission electron micrograph (TEM), pyridine adsorbed infrared spectra (Pyridine-FTIR) and temperature-programmed desorption of ammonia (NH3-TPD). The characterization results indicate that the final Meso-ZA possesses rhombus-shaped morphology, worm-like mesoporous structure, crystalline framework, narrow pore size distribution, large surface area (up to 216 m2/g) and rich surface Lewis acid sites. The catalytic test on phenol hydroxylation shows that the synthesized Meso-ZA exhibits a superior catalytic performances to titanium silicalite (TS-1) and bulk zinc aluminate.

Chemical doping of nickel hydroxide with other cations (e.g. Al3+) is an efficient way to enhance its electrochemical capacitive performances. Herein, a simple cation–anion (Ni2+ and AlO2−) double hydrolysis method was developed toward the synthesis of nickel–aluminum (Ni–Al) composite hydroxides. The obtained composite hydroxides possesses a porous structure, large surface area (121 m2/g) and homogeneous element distribution. The electrochemical test shows that the obtained composite hydroxides exhibits a superior supercapacitive performances (specific capacitance of 1670 F/g and rate capability of 87% from 0.5 A/g to 20 A/g) to doping-free nickel hydroxide (specific capacitance of 1227 F/g and rate capability of 47% from 0.5 A/g to 20 A/g). Moreover, the galvanostatic charge/discharge test displays that after 2000 cycles at large current density of 10 A/g, the composite hydroxides achieves a high capacitance retention of 98%, indicative of an excellent electrochemical cycleability.A simple cation–anion (Ni2+ and AlO2−) double hydrolysis method was developed toward the synthesis of nickel–aluminum (Ni–Al) composite hydroxides. The obtained composite hydroxides possesses a porous structure, large surface area (121 m2/g), homogeneous element distribution and exhibits a superior supercapacitive performances (specific capacitance of 1670 F/g and rate capability of 87% from 0.5 A/g to 20 A/g) to doping-free nickel hydroxide (specific capacitance of 1227 F/g and rate capability of 47% from 0.5 A/g to 20 A/g).

As one of the most promising candidates for supercapacitor electrodes, transition metal hydroxides usually suffer from the quick decay in capacity during cycling, mainly caused by the decrease of electroactive surface area resulting from the instability of microstructure/morphology upon fast and repeated charging/discharging. Herein, we fabricated a structure-stable Ni(OH)2 grown on Ni foam via in situ ion-exchange reaction with Mg(OH)2 as sacrificial substrate and effective dopant. The obtained hybrid Ni(OH)2 possesses nanosheet morphology, large surface area (220 m2/g) and achieves an unprecedented cycling stability with a 95% retention after 10 000 cycles. The asymmetric supercapacitors with the hybrid Ni(OH)2 exhibit superior supercapacitive performances with large capacity of 167 F/g and maximum energy density of 57.9 Wh/kg at power density of 1.58 kW/kg. Even at a standard power density of 4.0 kW/kg, a high energy density of 49.6 Wh/kg was achieved, making the hybrid Ni(OH)2 a promising candidate for practical supercapacitor devices.

We present a novel and facile fabrication of ultrathin gold nanowires in the absence of organic reagents. Measurements of surface-enhanced Raman scattering (SERS) demonstrated that the obtained organic-free ultrathin Au nanowires can serve as simple and effective SERS substrates.

Gold nanosheets (AuNSs) with well-tuned thicknesses were synthesized by a facile photochemical reduction method in lamellar liquid crystals. It is found that ∼50 nm thick AuNSs present much stronger surface-enhanced Raman scattering (SERS) effect than that of AuNSs with thicknesses of ∼8 nm and 100 nm.

We report a facile and efficient strategy for preparing flower-like hierarchical mesoporous carbon superstructures (FMCS) through a one-pot hydrothermal reaction of nickel acetate with glucose. In the fabrication process of FMCS, the nickel acetate ingeniously plays multifunctional roles: as inducer of flower-like hierarchical carbon, as catalyst of graphitization, and as pore-forming agent. First, flower-like Ni(OH)2/polysaccharide microspheres were self-assembled via a hydrothermal reaction at 180 °C for 24 h. Second, flower-like mesoporous carbon superstructures were obtained by etching and removing the Ni from the Ni/C precursor carbonized from the Ni(OH)2/polysaccharide microspheres. The obtained flower-like superstructures are composed of two-dimensional mesoporous carbon petal building blocks, with a thickness of 20 nm. Electrochemical data showed that the product FMCS-1 displayed a specific capacitance of 226 F g−1 at 0.5 A g−1, and retained 82% (185 F g−1) at a high current density of 20 A g−1, indicative of outstanding rate capability. Furthermore, the three-dimensional (3D) flower-like hierarchical mesoporous carbon superstructures demonstrated excellent cycling stability, with approximately 100% retention of the initial specific capacitance after 2000 cycles at a current density of 10 A g−1.

Uniform single-crystalline hydroxyapatite nanotubes with hexagonal facets are synthesized via a distinctive organoamines-assisted biomimetic route. These novel HA nanotubes exhibit exceptional performance in stimulating osteoblast proliferation, which gives them intriguing potential for bone repair.

In view of the fact that the catalytic activity of supported catalyst is greatly influenced by its impregnation method, an in situ hydrothermal deposition method was explored and applied to load iron catalyst onto the amorphous carbon matrix, which derived from a soft-templating method with sucrose as precursor, to prepare nanoporous graphitic carbon at low temperature. Compared to traditional impregnation method, this hydrothermal loading method could realize the phase transformation from amorphous carbon to graphitic carbon at a temperature as low as 650 °C. Systematical studies on the hydrothermal deposition and catalytic graphitization were made by X-ray diffraction and Raman spectrum, indicating that hydrothermal impregnation temperature and duration are the two crucial factors to the catalytic performance of loaded iron oxide. The obtained graphitic carbon by this approach possesses a nanoporous structure with surface area up to 329 m2/g, pore volume of 0.39 cm3/g and achieves a capacitance per unit surface area of 39.5 μF/cm2, much higher than that of the carbon derived from traditional impregnation method (24.6 μF/cm2).

•N-doped mesoporous carbons were synthesized from phenol–urea–formaldehyde resin.•The doped nitrogen content can be easily adjusted (0–3.85 wt. %).•The N-doped mesoporous carbon presents superior supercapacitive performances.With urea as nitrogen source, soluble phenol–urea–formaldehyde (PUF) resin is synthesized under basic conditions, and then an N-containing mesophase is obtained by co-assembly of the obtained PUF resin and block copolymer of F127 in acidic aqueous solution. The pyrolysis of the resultant mesophase in inert atmosphere produces a nitrogen-doped mesoporous carbon, which possesses a well-defined ordered mesoporous structure, large surface area (up to 537 m2/g), uniform pore size (∼3.6 nm) and large pore volume (∼0.49 cm3/g). Multi-techniques, such as elemental analysis, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) are performed to characterize the samples; these analytic results indicate that the doped nitrogen mainly exists as pyridinic and pyrrolic nitrogen is successfully and homogeneously introduced into the skeleton of the mesoporous carbon. And more, the nitrogen content in the final ordered mesoporous carbon can be easily adjusted up to 3.85 wt.% by increasing the original ratio of urea to phenol. Electrochemical measurements show the nitrogen doped mesoporous carbon presents a higher specific capacitance (up to 225 F/g) than nitrogen-free ones (169 F/g) and exhibits a good electrochemical stability even after 1000 cycles at current density of 5.0 A/g.Graphical abstractWith urea as nitrogen source, soluble phenol–urea–formaldehyde (PUF) resin is synthesized under basic conditions and then to co-assemble with block copolymer of F127 in acidic aqueous solution to fabricate nitrogen doped mesoporous carbon. Heteroatom of nitrogen is successfully and homogeneously introduced into the skeleton of the mesoporous carbon and the final doped carbon presents a higher specific capacitance (up to 225 F/g) than nitrogen-free one (169 F/g).

Hollow nanostructures afford intriguing structural features ranging from large surface area and fully exposed active sites to kinetically favorable mass transportation and tunable surface permeability. The unique properties and potential applications of graphene nanoshells with well-defined small cavities and delicately designed graphene shells are strongly considered. Herein, a mesoscale approach to fabricate graphene nanoshells with a single or few graphene layers and quite small diameters through a catalytic self-limited assembly of nanographene on in situ formed nanoparticles was proposed. The graphene nanoshells with a diameter of ca. 10–30 nm and a pore volume of 1.98 cm3 g–1 were employed as hosts to accommodate the sulfur for high-rate lithium–sulfur batteries. A very high initial discharge capacity of 1520 mAh g–1, corresponding to 91% sulfur utilization rate at 0.1 C, was achieved on a graphene nanoshell/sulfur composite with 62 wt % loading. A very high retention of 70% was maintained when the current density increased from 0.1 C to 2.0 C, and an ultraslow decay rate of 0.06% per cycle during 1000 cycles was detected.Keywords: battery; graphene; nanostructures; porous carbon; sulfur;

We report a novel approach to fabricate sandwich-like LiFePO4/graphene hybrid nanosheets as battery materials by means of in situ graphitizing organic interlayers (ISGOI). These sandwich-like LiFePO4/graphene nanosheets demonstrated high rate storage and excellent cycle stability.

A novel synergic evolution of dynamic assembly, from vesicles to nanotubes, between the metallophosphates and organic amines, is disclosed, by which the multicomponent metallophosphate (Cu2(OH)PO4) nanotubes are synthesized for the first time.

In view of the low reactivity of phenol with formaldehyde under acidic condition in the synthesis of ordered mesoporous carbons, a strategy to accelerate the polymerization of phenol and formaldehyde by using designed aqueous basic/acidic conditions (first weakly basic condition then highly acidic condition) is developed. The first weakly basic condition benefits the formation of hydroxymethyl phenols at 313 K. The latter highly acidic condition mainly induces the condensation reaction between the formed hydroxymethyl phenols, as well as the self-assembly of phenol–formaldehyde and block copolymer template. After removal of the template, the obtained carbon exhibits highly ordered hexagonal mesostructure with a surface area of 760 m2 g−1, large pore volume (0.64 cm3 g−1) and uniform pore size (3.32 nm). This developed strategy affords a simple and highly reproducible approach for the synthesis of ordered mesoporous carbon from the less expensive phenol under strong acidic condition, which also provides a wide and easily accessed synthesis condition for the further functionalization, such as the in situ introducing of metal ions.

Well-defined ceria nanocubes covered by oleic acid with exposed {100} facets have been synthesized and exhibited exclusive selectivity for the oxidation of toluene to benzaldehydes in liquid phase by O2.

Hierarchically porous intestine-like SnO2 hollow nanostructures of different dimension were successfully synthesized via a facile, organic template free, H2O2-assisted method at room temperature. The morphology as well as texture (congregated solid sphere, intestine-like solid nanostructure, hollow core–shell one, and intestine-like hollow one) of SnO2 materials can be controlled by varying H2O2 concentration and the size of intestine-like hollow SnO2 can be tuned in the range of 20–120 nm by changing SnSO4 concentration. The hierarchically porous intestine-like SnO2 has high specific surface area (142 m2 g−1). The gas-sensing behaviors of the intestine-like SnO2 material to different gas probes such as ethanol, H2, CO, methane, and butane have been investigated; among them a high selectivity to ethanol was achieved.

In the present study the intestine-like binary SnO2/TiO2 hollow nanostructures are one-pot synthesized in aqueous phase at room temperature via a colloid seeded deposition process in which the intestine-like hollow SnO2 spheres and Ti(SO4)2 are used as colloid seeds and Ti-source, respectively. The novel core (SnO2 hollow sphere)-shell (TiO2) nanostructures possess a large surface area of 122 m2/g (calcined at 350 °C) and a high exposure of TiO2 surface. The structural change of TiO2 shell at different temperatures was investigated by means of X-ray diffraction and Raman spectroscopy. It was observed that the rutile TiO2 could form even at room temperature due to the presence of SnO2 core and the unique core-shell interaction.

Fine control of the self-assembly of silicon species to hierachical materials has attracted research attention for many years. The mesostructures produced by such processes under weak acidic−basic conditions mimic bioenvironments are the focus of current research. In this study, mesoporous silicas with various novel morphologies such as mesoporous spheres, nanotubes, and oligomeric nanotubes have been systematically synthesized by using boric acid in the system, which is the key reagent for the fine control of the assembly of the silica precursors. The as-prepared materials are characterized using transmission electron microscopy (TEM), small-angle X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and nitrogen sorption measurements. The results support the assembly process of the nanomicelle of silica and surfactant under the conditions of boric acid, from which the synergistic weak interactions cause the morphology evolution of silicas. The current research provides effective information for understanding the formation of mesoporous silica under conditions mimicking biosilification processes.

Natural kingite-like aluminophosphate nanorolls were obtained by biomimetic synthesis using a mixed-organoamine template.

Ferric molybdate molybdate nanotubes prepared based on the Kirkendall effect and solid-state reaction exhibit a unique catalytic property for epoxidation of propene by molecular oxygen.

Gold nanosheets (AuNSs) with well-tuned thicknesses were synthesized by a facile photochemical reduction method in lamellar liquid crystals. It is found that ∼50 nm thick AuNSs present much stronger surface-enhanced Raman scattering (SERS) effect than that of AuNSs with thicknesses of ∼8 nm and 100 nm.

We present a novel and facile fabrication of ultrathin gold nanowires in the absence of organic reagents. Measurements of surface-enhanced Raman scattering (SERS) demonstrated that the obtained organic-free ultrathin Au nanowires can serve as simple and effective SERS substrates.

A novel synergic evolution of dynamic assembly, from vesicles to nanotubes, between the metallophosphates and organic amines, is disclosed, by which the multicomponent metallophosphate (Cu2(OH)PO4) nanotubes are synthesized for the first time.

Well-defined ceria nanocubes covered by oleic acid with exposed {100} facets have been synthesized and exhibited exclusive selectivity for the oxidation of toluene to benzaldehydes in liquid phase by O2.

We report a facile and efficient strategy for preparing flower-like hierarchical mesoporous carbon superstructures (FMCS) through a one-pot hydrothermal reaction of nickel acetate with glucose. In the fabrication process of FMCS, the nickel acetate ingeniously plays multifunctional roles: as inducer of flower-like hierarchical carbon, as catalyst of graphitization, and as pore-forming agent. First, flower-like Ni(OH)2/polysaccharide microspheres were self-assembled via a hydrothermal reaction at 180 °C for 24 h. Second, flower-like mesoporous carbon superstructures were obtained by etching and removing the Ni from the Ni/C precursor carbonized from the Ni(OH)2/polysaccharide microspheres. The obtained flower-like superstructures are composed of two-dimensional mesoporous carbon petal building blocks, with a thickness of 20 nm. Electrochemical data showed that the product FMCS-1 displayed a specific capacitance of 226 F g−1 at 0.5 A g−1, and retained 82% (185 F g−1) at a high current density of 20 A g−1, indicative of outstanding rate capability. Furthermore, the three-dimensional (3D) flower-like hierarchical mesoporous carbon superstructures demonstrated excellent cycling stability, with approximately 100% retention of the initial specific capacitance after 2000 cycles at a current density of 10 A g−1.

Uniform single-crystalline hydroxyapatite nanotubes with hexagonal facets are synthesized via a distinctive organoamines-assisted biomimetic route. These novel HA nanotubes exhibit exceptional performance in stimulating osteoblast proliferation, which gives them intriguing potential for bone repair.

We report a novel approach to fabricate sandwich-like LiFePO4/graphene hybrid nanosheets as battery materials by means of in situ graphitizing organic interlayers (ISGOI). These sandwich-like LiFePO4/graphene nanosheets demonstrated high rate storage and excellent cycle stability.

TiO2@carbon with a nanosheet morphology and core–shell structure was constructed by self-assembly/carbonization of P123, CTAB and exfoliated titanate nanosheets. The obtained composite possesses an ultrathin structure (∼5.5 nm) and exhibits high capacity (549 mA h g−1) and excellent cyclability (385 mA h g−1 after 2000 cycles at 4.6 A g−1) as an anode for Li-ion batteries.