A new MnO2@NiS2/Ni(OH)2 heterostructure material was synthesized using a two-step hydrothermal process. The presence of 1D MnO2 nanosticks provided a substrate for the junction and facilitated the charge transmission. The grafting of NiS2/Ni(OH)2 sheets onto the surface of MnO2 enlarged the specific surface area (SSA) of the material. As a result, the SSA of the electrode material was improved and the capacitor performance was optimized. The material also showed a high rate capacity and long-term cycling capability.

Steam explosion lignin phenol formaldehyde (SEL–PF) adhesives were prepared by ternary gradual copolymerization. The parameters for the phenolate of steam explosion lignin (SEL) and preparation of SEL–PF adhesives were optimized. Under the optimum phenolate conditions, the phenolic hydroxyl content of lignin increased by 130%, whilst the methoxyl content was reduced by 68%. The SEL–PF adhesives were used to prepare plywoods by hot-pressing. The pH value, viscosity, solid content, free phenol content and free formaldehyde content of SEL–PF adhesives were investigated. The bonding strengths of the plywoods glued with SEL–PF adhesives were determined. The maximum SEL replacement percentage of phenol reached 70 wt%, and the properties of adhesives and plywoods met the Chinese National Standard (GB/T 14732-2006) for first grade plywood.

•Hierarchical porous carbons are prepared from lignin (denoted as LAC).•Preparation parameters are discussed in detail.•LAC provides a specific surface area as large as 3775 m2 g−1.•The specific capacitance of LAC is as high as 286.7 F g−1 at 0.2 A g−1.Hierarchical porous carbons (HPCs) were prepared from lignin (denoted as LAC) via traditional carbonization-activation method. The resulting LAC prepared from lignin was composed with macroporous cores, mesoporous and microporous channels. The preparation parameters were discussed in detail in this paper. The LAC activated with a KOH–carbon ratio of 4:1 at 800 °C displayed the highest BET specific surface area of 3775 m2 g−1. The unique hierarchical structure of LAC provided LAC with favorable ion transportation paths and high ion-accessible surface area, which enhanced the electrochemical performance of LAC as electrode material of supercapacitor. The specific capacitance of LAC was as high as 286.7 F g−1 at a charge–discharge current density of 0.2 A g−1 in 6 mol L−1 KOH, and still retained 207.1 F g−1 at a high charge–discharge current density of 8 A g−1.

•The temperature of the reaction can be reduced to 100 °C and even lower.•The PL properties of pure LaF3 nanocrystals were assessed upon UV irradiation.•White light emission can be achieved only through Eu3+ doping.Mild molten salt synthesis (MSS) method was utilized to synthesize rare earth fluorides nanocrystals with favorable fluorescence efficiency. LaF3 nanocrystals were achieved through this modified MSS method by only using La(NO3)3·6H2O and NH4HF2 as starting materials. NH4HF2 is difunctionality as both fluorine source and the flux. The effects of reaction time and temperature to the synthesis of LaF3 nanocrystals were discussed in detail. The fluorescence of LaF3 nanocrystals was detected with excitation wavelength of 360 nm, the results showed a broad band emission centered at 475 nm. The photoluminescence properties of pure LaF3 nanocrystals and Eu3+ doped samples were also investigated. In our work, white light emission was achieved in single element (Eu3+) doped LaF3 nanocrystals by adjusting the concentration of Eu3+ ions. This would be the combination of broad emission of LaF3 nanocrystals and sharp line emission of Eu3+ in the LaF3:Eu3+ nanocrystals.

Special Tm3+ transition and a bright green light emission is first observed in the Yb3+/Tm3+ co-doped KMnF3, which are synthesized by the molten salt synthesis method. The RGB light emissions are simultaneously obtained with a single Tm3+ activator, and white upconversion luminescence is observed only by changing the reaction time.

Au/CNTs assembled at the interfaces of a Pickering emulsion are reported, for the first time, exhibiting good catalytic activity and 100% selectivity for the hydrodeoxygenation of vanillin to p-creosol under mild reaction conditions. Simultaneous reaction and separation of the target products are achieved, which leads to substantial simplification of the separation and purification process for bio-oil upgrading.

•Two useful materials (activated carbon and liquid compound fertilizer) were produced from rice husk.•This simple route combined the advantages of H3PO4 activation and KOH etching.•Activated carbon exhibited excellent adsorption and electrochemical performances.•All the chemicals involved in this route have been effectively used.Two useful materials (activated carbon and liquid compound fertilizer) were obtained from rice husk by a simple route which combined the processes of H3PO4 activation and KOH etching. The resulting activated carbon exhibited excellent performances, including low ash content, large surface area, high adsorption and electrochemical performances. The advantage of this route is that the waste water produced in this process was used to produce compound fertilizer containing Si, K and P. This technique provided an environmentally friendly production process for conversion of waste rice husk to high performance materials.

•Activated carbon treated by KOH exhibited better adsorption properties than untreated one.•Thermodynamic parameters demonstrated the adsorption process was spontaneous and favorable.•It was probable to deduce adsorption mechanisms and design adsorption systems by the study of adsorption kinetics, isotherms and thermodynamics.The adsorption of Rhodamine-B (RhB) onto treated rice husk-based activated carbon was investigated in this paper. The influences of initial RhB concentration, temperature and pH on dye adsorption were analyzed. Initial RhB concentration and temperature played important roles in this adsorption process, and pH had a little effect on RhB adsorption. Adsorption kinetics, equilibrium and thermodynamics study was carried out. Results demonstrated that pseudo-second order kinetic model represented the adsorption kinetics of RhB well. Adsorption equilibrium data were well described by Langmuir isotherm model. Thermodynamic parameters, including the Gibb's free energy change (ΔG), standard enthalpy change (ΔH) and standard entropy change (ΔS), revealed that this adsorption process was spontaneous and endothermic.

•Hydrochars was an excellent precursor to prepare high-performance porous carbon.•The porous carbons exhibited high specific surface area and large pore volume.•The porous carbons showed localized graphitic structure.•The products possessed good electrochemical performance.•This route could be extended to other biomass and industrial wastewater containing carbohydrates.In the present work, a sustainable route to prepare high-performance porous carbons from hydrochars by KOH activation was described. The hydrochars was obtained from sulfuric acid hydrolyzate of rice husk via dehydration, polymerization and carbonization. When the pretreated hydrochars (42%) was activated at 400 °C for 0.5 h and 800 °C for 1 h with the mass ratio of KOH/hydrochars of 5:1, the high specific surface area and large pore volume of the porous carbons reached 3362 m2/g and 2.20 cm3/g, respectively. The specific capacitance of 312 F/g was achieved using this product, which indicated the porous carbon had good electrochemical performance. Furthermore, the X-ray diffraction pattern and Raman spectroscopy showed the porous carbon had localized graphitic structure.

Charge ordering (CO) is an important phenomenon in mixed-valent transition metal oxides. In this communication, LaMnO3+δ crystals have been synthesized under high-pressure flux conditions and CO of Mn3+/Mn4+ is stabilized and retained at ambient pressure, because CO reduces the lattice strain induced by external pressure.

•Molten salt synthesis (MSS) method to synthesis KMgF3 and KMgF3:Eu crystals•The obtained KMgF3 crystals got a broad band blue emission at about 430 nm.•The KMgF3: Eu crystals exhibited fantastic emission under the excitation of different wavelengths.KMgF3 and KMgF3: Eu samples were firstly fabricated by molten salt synthesis (MSS) method in NH4HF2 flux without any surfactants. The NH4HF2 flux was utilized as both the reactant and the fluxing agent. The products with uniform and regular morphologies were characterized by X-ray diffraction (XRD), thermal stability (TG), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectra. The luminescent properties show that the obtained KMgF3 sample got a broad band blue emission at about 430 nm arising from the trace oxygen and the color center, and the KMgF3: Eu sample exhibited fantastic emission under the excitation of different wavelengths.Emssion spectra of the Eu-doped KMgF3 sample. The emission spectrum of the KMgF3 microcrystal, which was excited at 261–371 nm and at 352–382 nm.

The δ-MnO2 microspheres as well as the δ-MnO2 microspheres/α-MnO2 nanorods mixture were synthesized by reduction of KMnO4 under microwave irradiation. The morphology and structure of the as-prepared products were characterized by powder X-ray diffraction (PXRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) measurements and Raman spectra. Electrochemical performances of the samples were examined using cyclic voltammetry (CV) and galvanostatical discharge–charge test in Na2SO4 and Li2SO4 aqueous electrolyte, respectively. It was found that the nearly ideal rectangular shapes of the CV curves show that these samples exhibited good pseudo-capacitor properties in the voltage range from 0.0 to 1.0 V. The test of long-term cycling stability indicated that two samples all have a reasonably good stability. However, the δ-MnO2 microspheres possessed a lower specific surface area while a higher supercapacitance than those of the δ-MnO2 micropheres/α-MnO2 nanorods mixture did. The presence of a few fraction α-MnO2 impurities reduces the specific capacitance of δ-MnO2 electrode. Because of the crystal structure and morphologies are two such important parameters that have to be taken into account in this work.

Single crystal Dy3+ doped YNbO4 phosphors were prepared via a high-temperature high-pressure hydrothermal procedure. Under excitation at 270 nm, the Dy3+-doped YNbO4 phosphor shows bright white emission, which is composed of two strong bands at 492 and 576 nm corresponding to the characteristic 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions of Dy3+, respectively. The dominant band was observed at 352 nm, which corresponds to the 6H15/2→6P7/2 transition of Dy3+. Nearly white light was achieved at λex 270, 310 and 388 nm and the CIE(International Commission on Illumination) values were (0.3135, 0.3421), (0.3088, 0.3380) and (0.3146, 0.3296), respectively.

A sol–gel procedure in a water/oil emulsion was introduced for the synthesis of porous silica spheres. Tetraethoxysilane was used as the silica source. The specific surface area and total pore volume of the product reached 772.3 m2/g and 0.663 cm3/g, respectively. The electrolyte washing process conferred a surface charge to the product, which displayed self-dispersal properties in water. The porous spheres have potential applications in the fields of drug delivery, controlled release capsules, indoor air pollutant scavengers, and hydrogen storage agents. The oil phase, which accounts for over 80% of the chemical cost of the procedure, could largely be recycled by filtering, standing, and layering. The whole procedure is suitable for application as an industrial process.Graphical abstractSuggested formation mechanism of porous silica spheres.Highlights► Porous silica spheres were synthesized in a water/oil emulsion. ► Surface area and pore volume of the product could reach 772.3 m2/g and 0.663 cm3/g. ► Electrolyte washing process conferred self-dispersal properties to the product. ► Oil phase could be readily recycled to reduce chemical cost.