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CuInS 2 thin films incorporating with cerium have been successfully fabricated by a powder metallurgy method. X-ray diffraction and scanning electron microscope measurements showed that the as-prepared CuIn 1− x Ce x S 2 samples crystallize with chalcopyrite structure at 250 °C and the crystallinity and film compactness could be improved as annealing temperature rises. In the ultraviolet–visible–near infrared spectrum, two additional light absorption peaks were observed at 1690 nm and 1930 nm. The optical bandgaps of CuIn 1− x Ce x S 2 films decrease from 1.38 eV to 1.34 eV with increasing cerium content. These observed optical behaviors could suggest that an intermediate band forms in the forbidden band of CuInS 2 semiconductor due to cerium incorporation. The position of intermediate band locates at 0.64 eV below conduction-band bottom. This kind of rare-earth doped materials enhances long-wavelength absorption, which could be helpful for high-efficiency solar cells. [ABSTRACT FROM AUTHOR]

Abstract: The Raman spectra for SrBi4−x La x Ti4O15 (x=0.00–1.00) ceramic samples are investigated to explore the influence of doping on the structure of SrBi4Ti4O15. Lanthanum-doping results in the shifts of the Raman modes involved in the vibration of the cations at A site of the pseudo-pervoskite slabs, Bi3+ ions in the Bi2O2 layers, and the stretching mode of TiO6 octahedra. The shifts of these modes indicate that La3+ ions prefer the A site of SrBi4Ti4O15 as x≤0.10, and as x>0.10, they are incorporated into Bi2O2 layers. [Copyright &y& Elsevier]

Abstract: Porous spheres of CuSCN nanoparticles with an average diameter of 0.4–0.6 μm have been prepared by a simple reaction between CuO suspension, NH2OH and KSCN in the presence of gelatin at 10 °C. Gelatin played a decisive role as an inhibitor of the direct attack of NH2OH, KSCN to CuO surfaces and coagulation of the growing CuSCN in producing porous spheres. The products were characterized by X-ray powder diffraction, transmission electron microscopy, and X-ray photoelectron spectra techniques. [Copyright &y& Elsevier]

A convenient sonochemical process for the preparation of HgSe nanoparticles by using different reductants has been discovered. The HgSe nanoparticles, which were prepared in polyethylene glycol 400 (PEG 400), dextrose and hydroxylamine reductive systems, were analyzed by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that all the products were cubic phase HgSe by XRD measurements. The TEM observations showed that the HgSe nanoparticles were monodispersed and electron diffraction images of selected areas show that the products were polycrystalline. The sizes of most of all the HgSe nanoparticles were mainly among 30–40 nm, which were in coincidence with the very sizes that were estimated by Debye–Scherrer equation from the XRD patterns. XPS result showed that the ratio of Hg to Se was 57:43, indicating that the final products were rich in mercury. [Copyright &y& Elsevier]

Nanocrystalline SnO2 powders of about 3 nm in size have been prepared by a microwave irradiation heating technique from an aqueous solution in the presence of SnCl4 and urea. The nanocrystalline SnO2 particles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetric (DSC), thermogravimetric analysis (TG), and reflection spectrum. A bandgap is estimated to be 4.5 eV from the optical measurement of the nanoparticles. [Copyright &y& Elsevier]

• Silver nanorods/nanowires were prepared within the range of sub-20 nm diameter. • The diameter can be controlled, as small as 12 nm, using 5-nm spherical Au seeds. • One-dimensional trimetallic (Au@Pd-Ag) hollow products were prepared via GRR. We report a facile synthesis of silver nanorods/nanowires with the diameter in the range of sub-20 nm via seeded growth. The key to the success of this work relies on the use of tiny Au seeds and manipulation over reaction kinetics. In particular, their diameter could be controlled to as small as 12 nm using 5-nm spherical Au seeds. They can be further converted to trimetallic (Au@Ag-Pd) hollow derivatives with tunable hollow degree and elemental compositions by galvanic replacement reaction. [ABSTRACT FROM AUTHOR]

In present paper, a promising intermediate band (IB) material of CuGaS 2 thin films incorporating with titanium (Ti) have been successfully fabricated by a facile non-vacuum method. Binary sulfides used as raw material are firstly tried to fabricate Ti-substituted CuGaS 2 thin films via ball milling and spin-coating technique. The experimental measurements showed that the obtained Cu 2 Ga 1− x Ti x S 2 thin films are composed of chalcopyrite structure with well crystallinity. A slightly left shift of (1 1 2) diffraction peaks indicated the successful doping of Ti element. The Hall Effect measurement exhibited the carrier concentration raised obviously from 1.538 × 10 12 ( x = 0) to 1.134 × 10 13 cm −3 ( x = 0.06) with increasing of Ti doping concentration. More important, the UV–vis–NIR spectra exhibited a strong optical absorption in Ti-substituted CuGaS 2 films, which indicated the IBs were roughly formed in the films. [ABSTRACT FROM AUTHOR]

Titanium has been incorporated into the copper gallium disulfide (CuGaS 2 ) thin film by sulfurizing Cu-Ga-Ti precursor, which has been obtained through magnetron co-sputtering. The structure, chemical composition and optical property of the Ti-doped CuGaS 2 film were analyzed by Energy Dispersive X-ray Analysis (EDAX), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and ultraviolet–visible spectrophotometer. The results indicated that the Ti element has doped into CuGaS 2 thin film successfully. The crystal structure of Ti-doped CuGaS 2 thin films was single-phase chalcopyrite structure. By doping Ti element, the (112) diffraction peaks shift slightly. The optical band gap values of Ti-doped CuGaS 2 thin films were 2.30 eV and 1.92 eV with different Ti concentrations of 0.53 at% and 0.82 at%. [ABSTRACT FROM AUTHOR]

Abstract: Antimony dendrites have been successfully synthesized by a microwave-assisted method under ambient air from the solution containing antimony sodium tartrate. In the reaction, zinc powders were selected as a reductant for the fabrication. The as-prepared products were characterised by X-ray powder diffraction, transmission electron microscopy, and selected area electron diffraction. The dendrites were found to be composed of well-crystallized nanoflakes with size of 20–40 nm. [Copyright &y& Elsevier]

A novel intermediate band (IB) material of Zn incorporation in Ti-doped CuGaS 2 thin films has been successfully fabricated via a facile non vacuum method including ball milling, spin-coating and annealing. Experimental results have shown that the IB position of Ti-doped CuGaS 2 thin films can be adjusted by Zn incorporation. In this study, the optical band gap has a shortening of 0.19 eV when 0.6% Zn is added to the 1.5% Ti-doped CuGaS 2 . Due to the Zn addition, the grains grow larger, which is observable from the surface morphology of the thin films using scanning electron microscope (SEM). The energy dispersive X-ray analysis (EDAX) spectrum demonstrates that ball milling can effectively make Ti and Zn elements co-coped evenly into CuGaS 2 thin films. Moreover, the improved optical property of the Ti-doped CuGaS 2 thin films due to the Zn incorporation also sheds lights in developing new material that could be a potential light absorption layers candidate of high efficiency solar cells. [ABSTRACT FROM AUTHOR]

Abstract: The diameter-controllable SnO2 porous structures were fabricated by templating against the polystyrene nanospheres. The porous SnO2 nanostructures present efficient photocatalytic performance in degradation of MO under violet light, which has rarely been reported in the past. The photocatalytic ability can be enhanced through decreasing the porous diameter. Spectral examinations and analyses reveal that the porous structures and the existing oxygen vacancies are responsible for the appearing photocatalytic ability. Such porous structure is also expected to present good performance in gas sensing and electrochemical properties. [Copyright &y& Elsevier]

Abstract: PbS and Bi2S3 nanocrystals with well-controlled sizes and shapes were easily produced from molecular precursors (xanthate) in ethylene diamine (en) solution at room temperature. When lead or bismuth ethylxanthate were added into en solution, the precipitates were instantly formed, and subsequently, PbS cubes and flower-like Bi2S3 hierarchical structures were obtained if the mixtures were left still for 5days under ambient conditions. This work not only provides a facile route to synthesize chalcogenides with well-defined nano- and microstructures in a solution-phase system, but also gives insight into understanding on decomposition behavior of molecular precursors in various solvents. [Copyright &y& Elsevier]

This paper presents a novel method for the preparation of copper monosulfide (CuS) and nickel monosulfide (NiS) nanoparticles via a sonochemical route from an aqueous solution containing metal acetate [Cu(CH3COO)2 or Ni(CH3COO)2] and thioacetamide (TAA) in the presence of triethanolamine (TEA) as a complexing agent under ambient air. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray analysis (EDAX). The as-prepared nanoparticles have regular shape, narrow size distribution and high purity. It is found to be a mild, convenient and efficient method for the preparation of CuS and NiS nanoparticles. [Copyright &y& Elsevier]

Abstract: Facile pyrolytic synthesis of copper zinc thin sulfide (Cu2ZnSnS4) thin films are first introduced into quantum dot sensitized solar cells (QDSCs) for the counter electrode. The pore size of the pyrolytic synthesis Cu2ZnSnS4 thin films is from 100nm to 300nm, and its charge transfer resistance is 37.10Ω. The assembled QDSCs with the pyrolytic synthesis Cu2ZnSnS4 thin films give short circuit photocurrent density (J sc) of 13.33mAcm−2, open circuit voltage (V oc) of 0.52V, and fill factor (FF) of 0.45, corresponding to the photoelectric conversion efficiency (η) of 3.14%, while the QDSCs with platinized conducting glass give J sc of 13.38mAcm−2, V oc of 0.51V, and FF of 0.34, corresponding to the η of 2.32%. Because the pyrolysis procedure is a facile, low cost and vacuum-free process, and has the advantage of obtaining various porous microstructure thin films and allowing deposition over large areas, the pyrolytic synthesis Cu2ZnSnS4 thin films can be a promise alternative to the noble Pt counter electrode in QDSCs. [Copyright &y& Elsevier]

Abstract: Nanocrystals of [Eu2(BDC)3(H2O)2] n (1), a lanthanide-containing metal-organic framework (MOF) with a two-dimensional layer structure, were synthesized by using a surfactant-assisted hydothermal method. Nanorods with different sizes were prepared in the presence of a cationic surfactant, cetyltrimethyl ammonium bromide, depending on various reaction times. To demonstrate the ability of 1 nanorods for detection of nitroaromatic explosives, the fluorescence quenching and fluorescence titration experiments were carried out. Fluorescence of 1 nanorods was found to be highly sensitive to the nitroaromatics such as 2-nitrotoluene, 4-nitrotoluene, 2,4-dinitrotoluene, and 2,6-dinitrotoluene, suggesting that lanthanide-containing MOF nanocrystals can be excellent candidates for the rapid detection of nitroaromatic explosives. [Copyright &y& Elsevier]

Abstract: A photochemical reaction route was developed to synthesize bismuth selenide (Bi2Se3) nanoparticles and nanorods. In an aqueous solution, bismuth nitrate (Bi(NO3)3) reacted with sodium selenosufate in the presence of reducing agent and complexing agent, and the dispersed Bi2Se3 nanoparticles were obtained with the average size of 35 nm. The nanorods were prepared via an alumina template route in the same solution. We carried out experiments to study the formation mechanism in the morphology control of the products and found that series of factors played an effective role including the irradiation time, pH value, the reducing agents and the species of complexing agents. The products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). [Copyright &y& Elsevier]