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Two-dimensional porous carbon nanosheet materials are of increasing importance. Many examples for their synthesis exist, but they generally show some common requirements, such as rigid reaction conditions, high cost and complicated multiple synthetic steps. Here we report a facile and cost-effective way to prepare porous carbon nanosheets by using an exfoliated nanopaper-like biomass, i.e., melaleuca bark as precursor. It is found that just after a simple carbonization treatment, the nanopaper-like barks can be directly transformed into two-dimensional carbon nanosheets with a unique hierarchical porous structure. A high BET surface area of 1397 m2/g can be reached for the obtained carbon materials without any extra activation process. Tuning of nanostructures could be facilely accomplished by varying carbonization treatment conditions. The as-prepared porous carbon nanosheet serves well as the sulfur host materials for lithium-sulfur battery.

The hierarchical carpet-like WO 3 microflowers were synthesized via a facile one-step hydrothermal method by using oleic acid as a oriented growth reagent. The as-synthesized WO 3 microflowers show a triclinic crystal structure and are basically hierarchical assemblies of carpet-like nanosheets made up of the subunit of bundle-like nanowires. Based on the morphology evolution process, a possible crystal growth and nanostructure assembling mechanism were proposed. The prepared WO 3 microflower sensor exhibits a gas sensing response of about 228 when exposed to 10 ppm of toxic NO 2 gas at 200 °C.

The synthesis of ultrasmall upconversion nanophosphors is of great importance due to their potential applications in biomedicines. In this report, sub-5 nm monodispersed cubic NaYF 4 : Yb 3+ /Er 3+ nanocrystals were synthesized by a facile method. The nanocrystals have been well characterized and the average diameter was determined to be about 3.5 nm ±0.4 nm, which is one of the smallest grain sizes for NaYF 4 : Yb 3+ /Er 3+ nanocrystals ever reported. The size of the nanocrystals can be modulated by increasing the reaction temperature. Other reaction conditions including contents of OA and ODE as well as amount of NaOH were also investigated and their effects on the phase and morphology of NaYF 4 : Yb 3+ /Er 3+ nanocrystals have been elucidated.

Afterglow materials are of increasing importance. Here we report for the first time an intense long-lasting blue afterglow observed in a metal-activator-free boric acid calcined product. It was found that the afterglow intensity varied with the calcination temperature and reaches a maximum at around 250 °C, with a high phosphorescence lifetime of 1.87 s under 254 nm excitation (more than 25 s to the naked eye). Defects formed during the calcination process are associated with oxygen vacancies, which store the energy and are thought to be the origin of the afterglow. The as-prepared boric acid calcined product serves well as an afterglow material for anti-counterfeiting and time-resolved information protection.

The ordered mesoporous carbons (OMCs) with fiber-like and rod-like morphologies were selectively synthesized through a simple method and their electrochemical properties has been investigated. The conventional fiber-like SBA-15 was employed as hard template and sucrose as carbon precursor. When the infiltration process under static conditions or stirring for 24 h, the result carbons exhibited fiber-like (OMC-1) or rod-like (OMC-2) morphologies, respectively. Detailed characterizations of the samples revealed that, though the BET surface areas and pore volumes of OMC-2 (1217 m 2 /g and 1.23 m 3 /g, respectively) were slightly lower than those of OMC-1 (1358 m 2 /g and 1.53 m 3 /g, respectively), the electrochemical behavior of OMC-2 was abnormally better than OMC-1. The specific gravimetric capacitance was 162 F/g at a scan rate of 2 mV/s and the retained ratio was 82% at 50 mV/s for OMC-2, which was 151 F/g and 79% for OMC-1, respectively. Therefore, the as-prepared carbon, especially OMC-2 can be a potential candidate for supercapacitors.

Sulfur-doped carbon microspheres (SCMSs) with large surface area were prepared on large scale by a simple hydro-sulfur-thermal carbonization (HSTC) method using starch as carbon precursor. The morphology and composition of the resulted SCMSs were characterized by scanning emission microscopy, X-ray diffraction, Raman spectrum, and X-ray photoelectron spectroscopy. Experimental results show that monodispersed SCMSs can be obtained by the HSTC of starch under high concentration conditions (up to 1.0 g mL−1) by this HSTC method. The as-prepared SCMSs exhibit an enhanced hydrogen storage capacity (3.3 wt% at 77 K and 0.7 MPa) in comparison with the sulfur-free carbon microspheres (0.98 wt%).

Hierarchical TiO 2 hollow spheres had been prepared based on bubble templates by a simple one-step hydrothermal method. The diameter of hollow spheres was about 700 nm and the shell thickness of them was 69 nm. They were composed of similar spindle- or needle-like building units. Furthermore, hydrothermal time had an important influence on the morphology and crystallinity of hollow spheres. Moreover, the UV–Vis diffuse reflectance spectra of TiO 2 hollow spheres heated at 150 °C for 10 h showed the strongest absorption in the UV–Vis region and the Raman spectrum demonstrated the anatase sample. Additionally, a possible formation mechanism of TiO 2 hollow spheres was proposed. So this novel and simple method would provide a development direction to fabricate all kinds of inorganic hollow spheres by one-step procedure.

Copper-supported ordered mesoporous carbon (Cu/CMK-3) was prepared by impregnating ordered mesoporous carbon (CMK-3) with CuCl2 aqueous solution. CMK-3 was served as a carrier for the continuous immobilization of Cu. The supported copper was observed to be the bivalence state, indicating that the Cu2+ ion was not reduced into cuprous species or metallic copper in the CMK-3. The BET surface area and pore volume of Cu/CMK-3 were 728 m2/g and 0.95 cm3/g, respectively. The antibacterial activities of Cu/CMK-3 were tested by means of minimal inhibitory concentration (MIC) and viable cell counting method. The results show that Cu/CMK-3 presents a good antibacterial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which indicates its potential applications as antibacterial material for microbiocides.

A new method for synthesis of nanocrystalline titanium nitride was developed through the reaction of titanium oxide and sodium amide at 500–600 °C for 12 h in an autoclave. X-ray diffraction (XRD) and electron diffraction (SAED) results indicated the product had a cubic phase with lattice parameter a = 4.242 A. Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) revealed that the particle sizes were 10 to 40 nm. Quantitative analysis using X-ray photoelectron spectrum (XPS) showed the atomic ratio Ti:N was 1.03:1.

The conductivity of research salts has been studied in dimethylsulfoxide (DMSO) at 298 K. The experimental results indicate that La(ClO 4 ) 3 has strong electrolyte property in DMSO. Cyclic voltammetry is used to investigate the electrochemical behavior of La 3+ ion in the 2.5 × 10 − 3 mol L − 1 La(ClO 4 ) 3 –7.5 × 10 − 2 mol L − 1 LiClO 4 -DMSO system on a Pt electrode. Some electrochemical parameters indicate that the reduction of La 3+ ion is irreversible. The pulse deposition technique is used to prepare La–Ni–Co alloy films. The surfaces of La–Ni–Co alloy films are uniform, adhesive, compact and showed a metallic luster. The grain sizes of La–Ni–Co alloy observed by scanning electron microscope (SEM) are nanometer or submicron degree. La–Ni–Co alloy film is amorphous as proven by the X-ray diffraction (XRD). The magnetic properties of the amorphous La–Ni–Co alloy film are measured. The saturated magnetization intensity ( M s ), coercive force ( H c ) and remanence ( B r ) are 23.53 emu g − 1 , 214 Oe and 11.68 emu g − 1 , respectively.

Cubic boron nitride nanorods (cBNNRs) were synthesized through a simple reaction between boron tribromide and sodium amide in lithium bromide molten salt medium at 600 °C in a sealed autoclave system. The cBNNRs observed by transmission electron microscopy have various diameters ranging from 8 to 25 nm with aspect ratios of about 10–20. X-ray diffraction and selected area electron diffraction pattern revealed the cubic phase of cBNNRs with a lattice constant a =3.625 A. The B:N ratio obtained by energy dispersive X-ray spectroscopy was 1:1.12, and Fourier transform infrared spectrum showed a characteristic absorption at 1106 cm –1 . The possible formation mechanism of cBNNRs in molten salt medium is also discussed.

The structure and antibacterial activity of silver-carried zirconium phosphate (AgZrP) were investigated by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and viable cell counting method. There existed the exchange of sodium ions with silver ions in carrier, and the silver in AgZrP was in ionic state. Moreover, no significant changes in crystal structure of carrier were found by the exchange of silver ions except for its crystal space distance and crystallinity. The antibacterial tests showed that 100 mg l− 1 of AgZrP possessed high antibacterial activity and was capable of killing all the Escherichia coli (E. coli) and more than 99.9% of the Staphylococci aureus (S. aureus) within 8.0 h of contact.

Carbon micro-spheres with a regular and perfect shape, high yields and narrow size distribution were successfully synthesized by a hydrothermal route in a stainless steel autoclave. In this process, the aqueous glucose solution was used as starting materials. The optimal reaction conditions for obtaining carbon micro-spheres were 500 °C and 12 h. The resulting products were characterized by using combined techniques including X-ray powder diffractometer (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDX) and Raman spectroscopy. The diameters of carbon micro-spheres ranged from 1 to 2 μm.

Nanocrystalline hexagonal boron nitride (h-BN) nanoropes with diameters of 60–150 nm and with lengths up to several micrometers have been successfully synthesized by reacting KBH4 and NH4Cl using CoCl2 as the catalyst. The products were characterized by X-ray powder diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), energy dispersive spectrum (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cobalt chloride (CoCl2) played a key role in the formation of the rope-like nanostructure.

A novel chemical synthesis technique that a large quantity of rod-shaped LaNi5 alloy has been successfully synthesized using a solid reduction method was reported. The as-prepared alloy, proven via the XRD spectrum, was single-phased and hexagonal. The SEM and TEM photographs showed that the alloy was rod-shaped with a diameter in the range of 300–500 nm, and length of about 6–10 μm. The SAED pattern of LaNi5 alloy clearly indicated the orientation alignment along the c-axis.