Effective Doping of Rare-earth Ions in Silica Gel: A Novel Approach to Design Active Electronic Devices

Nano-Micro Letters - Eu3+ luminescence spectroscopy has been used to investigate the effective doping of alkoxide-based silica (SiO2) gels using a novel pressure-assisted sol-gel method. Our...     

Self-assembly of the Ag deposited ZnO/carbon nanospheres: A resourceful photocatalyst for efficient photocatalytic degradation of methylene blue dye in water

Carbon nanospheres (CNSs) are synthesized by pyrolysis of benzene at 1000?°C. Various UV-light photocatalysts of ZnO/CNSs and Ag-ZnO/CNSs (AZCN) composites are synthesized on the surface of CNSs using a facile chemical precipitation method. Morphological and optical properties of the as-synthesized photocatalysts are characterized by scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy, UV-Vis spectroscopy, photoluminescence and Raman spectroscopy. Photocatalytic degradation efficiency of methylene blue dye is investigated to examine the photocatalytic activity of synthesized photocatalysts. It is found that as-synthesized ZnO/CNSs composite can degrade higher methylene blue dye (～85.6%) after 25?min of UV irradiation in comparison with that of CNSs. A prominent improvement in the photodegradation is attained by depositing metal (Ag) particles on the surface of ZnO/CNSs composite. AZCN composite displays the enhanced photocatalytic degradation performance (～95% after 15?min of UV light) in high concentration of methylene blue dye. Furthermore, stability performance is studied by recycling the AZCN composite photocatalyst. It is found that the photocatalytic activity of AZCN composite is only slightly decreased even after five cycles. Present work demonstrates that AZCN composite show a great potential in the treatment of organic pollutants for wastewater treatment.     

CdSe quantum dots sensitized nanoporous hematite for photoelectrochemical generation of hydrogen

A novel system of CdSe quantum dots (QDs) sensitized porous hematite (α-Fe₂O₃) films has been investigated as a potential photoelectrode for hydrogen generation via photoelectrochemical (PEC) splitting of water. Before sensitization, nanoporous hematite thin films were prepared by spray pyrolysis. Characterizations for crystalline phase formation, crystallite size, absorption spectra, and flatband potential were carried out to analyze PEC data. Loading time of sensitizer to hematite thin films was found to be crucial in affecting its PEC properties. Film having sensitizer loading time as 42 h exhibited best photocurrent density of 550 μA cm⁻² at 1.0 V versus SCE. Current study, for the first time, explores the possibility of using low band gap QDs sensitization on a low band gap film, hematite in PEC splitting of water.     

Thermal,FT-IR and dielectric studies of gel grown sodium oxalate single crystals

Oxalic acid metabolism is important in humans, animals and plants. The effect of oxalic acid sodium salt is widely studied in living body. The growth of sodium oxalate single crystals by gel growth is reported, which can be used to mimic the growth of crystals in vivo. The grown single crystals are colourless, transparent and prismatic. The crystals have been characterized by thermogravimetric analysis, FT-IR spectroscopy and dielectric response at various frequencies of applied field. The crystals become anhydrous at 129·3°C. Coats and Redfern relation is applied to evaluate the kinetic and thermodynamic parameters of dehydration. The dielectric study suggests very less variation of dielectric constant with frequency of applied field in the range of 1 kHz-1 MHz. The nature of variation of imaginary part of complex permittivity, dielectric loss and a.c. resistivity with applied frequency has been reported.     

Functionalized core-shell nanostructures with inherent magnetic character: Outperforming candidates for the activation of PMS

With a view to engender an advanced oxidation protocol, in the present investigation a very efficient and outperforming catalytic system has been developed which employs peroxymonosulphate (PMS) as oxidant and surface metal functionalized core-shell nanostructures (with ferrite as core coated with shell of dopamine and surface functionalized with transition metal nanoparticles) as catalysts. The present protocol bids fast and facile degradation of organic pollutants without the aid of any promoting radiations. Every component of the developed core-shell nanostructures (M@Dop@CoFe; M?=?Cr, Mn, Fe, Co, Ni, Cu and Zn) has been found to contribute synergistically in the overall oxidative-degradation process. Co@Dop@CoFe presented the best results for the oxidative-degradation of nitrophenols (NP) taken as model pollutants with rate constant values of 8.13?×?10^?1?min^?1, 3.56?×?10^?1?min^?1 and 17.15?×?10^?1?min^?1 for 2-NP, 3-NP and 4-NP respectively. The synthesized core-shell nanocatalysts have been established to be leach-proof and recyclable to a very good extent.