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The design of sensitive and efficient photo catalyst for the energy and environmental applications with minimum charge recombination rate and excellent photo conversion efficiency is a challenging task. Herein we have developed a nonmetal doping methodology into ZnO crystal using simple solvothermal approach. The boron (B) is induced into ZnO. see more The doping of B did not make any significant change on the morphology of ZnO nano rods as confirmed by scanning electron microscopy (SEM) without considerable change on periodic arrangement of nanostructures. The existence of B, Zn, and O is shown by energy dispersive spectroscopy (EDS). The X-ray diffraction (XRD) patterns are well matched to the hexagonal phase for both pristine ZnO and B-doped ZnO. The XRD has shown slight dislocation of 2theta degree. The UV-visible spectroscopy was used to measure the optical bandgap and photo catalytic activity for the degradation of organic dyes. The nonmetal doped ZnO has shown potential and outstanding photo catalytic activity for the photo degradation of methylene blue (MB), methyl orange (MO) and rhodamine B in aqueous solution. The photo degradation efficiency of MB, MO and rhodamine B is found to be 96%, 86% and 80% respectively. The enhanced photo catalytic activity of B-doped ZnO is indexed to the inhibited charge recombination rate due to the reduction in the optical bandgap. Based on the obtained results, it can be said that nonmetal doping is excellent provision for the design of active materials for the extended range of applications.An overview is given of the many applications that nm-thin pure boron (PureB) layers can have when deposited on semiconductors such as Si, Ge, and GaN. The application that has been researched in most detail is the fabrication of nm-shallow p+n-like Si diode junctions that are both electrically and chemically very robust. They are presently used commercially in photodiode detectors for extremeultraviolet (EUV) lithography and scanning-electron-microscopy (SEM) systems. By using chemicalvapor deposition (CVD) or molecular beam epitaxy (MBE) to deposit the B, PureB diodes have been fabricated at temperatures from an optimal 700 °C to as low as 50 °C, making them both front- and back-end-of-line CMOS compatible. On Ge, near-ideal p+n-like diodes were fabricated by covering a wetting layer of Ga with a PureB capping layer (PureGaB). For GaN high electron mobility transistors (HEMTs), an Al-on-PureB gate stack was developed that promises to be a robust alternative to the conventional Ni-Au gates. In MEMS processing, PureB is a resilient nm-thin masking layer for Si micromachining with tetramethyl ammonium hydroxide (TMAH) or potassium hydroxide (KOH), and low-stress PureB membranes have also been demonstrated.Here we discuss the aerosol-assisted synthesis of p-n heterojunction metal oxides and we report their gas sensing properties via a short review of the latest results achieved. In particular, we show that the decoration of one-dimensional tungsten oxide (n-type) with nanoparticles of different p-type oxides from transition metals such as Ni, Co or Ir enables achieving a chemical and electronic sensitization of the resulting hybrid metal oxide materials. This leads to remarkable differences in responsiveness to gases, showing that, to some extent, a selective detection of some major pollutant gases (NO₂, H₂S or NH₃) would be possible. Results are critically reviewed, shortcomings are identified and future research directions are given.In the present manuscript the authors show the progress recorded regarding the main synthesis methods of metal endo-fullerenes. Shown, that nowadays, the most productive and common method of producing endohedral fullerenes is the electric arc process due to the fact that (a) it is simple enough to introduce atoms into the plasma from solids and gases; (b) its performance is the highest among other methods; (c) gives a wide range of produced types of metallofullerenes in an inert atmosphere-mono-, di-, tri-metalfullerenes, metal carbide clusters, in a reactive atmosphere (N₂, NH₃)-metal nitride and cyanide clusters, heterofullerenes; (d) provides the greatest energy potential, which is likely to allow the introduction into the cells of fullerene molecules metal atoms with higher ionization energies than titanium (≥7 eV). The yield of metal endofullerenes is substantially higher than the "empty" fullerenes. In this case, the stabilization of both metal atoms and fullerene cells occurs. The quantitative and qualitative output of MEF is significantly affected by (a) conditions of the process in the reactor the gas pressure, its flow rate, temperature, amperage; the distance between the electrodes, and others, that is, those factors that determine the plasma temperature and the residence time of the reaction particles in it; (b) the composition of solid additives (salts, oxides, metal alloys) in the graphite anode and their quantitative (mol) ratio with carbon; (c) replacement of the inert atmosphere of the synthesis with the active one (helium-with nitrogen, ammonia, water vapor, CO and other gases).Fullerenes-A new combining atoms of carbon atoms into the molecule, which can serve as the parent and precursor of a whole class advanced organic compounds. Unsolved problems associated with a correct understanding of the structure, transformation, and behavior of the fullerene C60 molecule, make it impossible to interpret correctly many of its physicochemical properties. Fullerenes are a new compounds of carbon atoms into a molecule that can serve as the parent and precursor of the whole class of the newest organic compounds. Unresolved problems connected with correct understanding of structure, transformation and behavior of fullerene molecule C60, do not allow to interpret many of its physico-chemical properties correctly. Since the discovery of fullerenes and the subsequent study of their properties, the interaction of fullerenes with metals is of fundamental interest. C60-building block (molecule), is similar to the atom, which can be used to create new materials. It has its physical and chemical propertzation are discussed.In the present study, equilibrium parameters of adsorption of bisphenol A (BPA) on multi-walled carbon nanotubes were determined using non-linear Langmuir and Freundlich sorption models and regression methods were applied. In the calculations, some error functions were applied in the non-linear regression analysis, the best fit between the data being obtained, for a minimum error distribution. Non-linear regression analysis and the error distribution suggested Langmuir isotherm model the best one for estimation of equilibrium parameters. The results will be further used in environmental applications for BPA removal from natural waters, taking into account the spontaneous character of the adsorption process, the endocrine disrupting effect of BPA and the reduced toxicological effects of the impregnated sorbents.Fullerenes that violate the isolated pentagon rule are too reactive and were obtained only as endoor exohedral derivatives. Density functional theory using the B3LYP hybrid density functional was applied to investigate the electronic and structural properties of the ten smallest tetrahedral (Td or T point group) fullerenes containing four directly fused pentagon-triples. The influence of nitrogen doping and exohedral hydrogenation of the four reactive sites was also analyzed. Nucleus independent chemical shifts values computed using B3LYP/6-31G(d) are used as global and local aromaticity probe. The global strain energy is evaluated in terms of the pyramidalization (POAV) angle. The results show that the stability increases with the elimination of the energetically unfavorable strain.Nitrogen doped multi-walled carbon nanotubes and other carbon nanoparticles were synthesized by catalytic chemical vapor deposition of tripropylamine and acetylene on CaCO₃-supported cobalt catalyst (5 wt%), prepared by impregnation, and various precursors. Each synthesis was performed by using either the pure nitrogenous organic compound or its mixture with acetone. Transmission electron microscopy studies revealed a significant difference both in the yield and the diversity of the carbon deposits. Every synthesis resulted in bamboo-like nanotubes, and nearly all of them also in onion-like structures. Electron energy loss spectroscopy studies of the samples indicated the presence of nitrogen and calcium (caused by the catalyst support). High-resolution transmission electron microscopy and X-ray diffraction measurements were also performed to characterize the samples.Experimental (IR, Raman and NMR) techniques and quantum chemical (DFT) methods have been applied to investigate the vibrational and NMR properties of a new ligand based on 2,2'-biquinoline (bq) functionalized with polar hydrophilic tetraethylene glycol monomethylether (TEG) chains (bq_TEG). Vibrational and NMR spectra of the ligand have been explained based on DFT computational data obtained at B3LYP/6-311+G(d,p) level of theory. For the spectroscopic analysis we started from the parent molecule 2,2'-biquinoline and explained the changes in the spectra of bq_TEG in close relation to the corresponding spectra of bq. Our data point to a trans conformation of bq_TEG in solid state, as wells as in liquid phase. The excellent agreement between the experimental and computed data allowed for a reliable assignment of the vibrational and NMR spectra, both for bq and bq_TEG.Application of multiwall carbon nanotubes (MWCNT) as a filler component in composite materials can lead to remarkable increase in mechanical strength. It is a challenging application to form a living bone tissue biocomposite that is reinforced with MWCNTs at a dental implant-bone interface. The successful biointegration of MWCNT and the implant material depends on the processes of osseointegration, namely surface interactions at the molecular and cellular level. In this work the compatibility of MWCNT with main osseointegration processes has been overviewed with special attention to the toxicity of MWCNT for interacting human cells, and In Vitro experiments were performed with primary human osteoblast cells. The cells were isolated from oral bone fragments and grown in cell culture conditions. Plate wells were covered with MWCNT layers of three different densities. Osteoblast cell suspensions were placed onto the MWCNT layers and into empty plate wells. 24 and 72 hours after seeding the attachment and proliferation of cells was evaluated using Thiazolyl Blue Tetrazolium Bromide (MTT) colorimetric assay. The extent of cell death was characterized by Lactate Dehydrogenase (LDH) assay. The osteoblast cell viability tests show that cells were attached to all investigated surfaces, but with lower rate to higher density MWCNTs. A low level of cell death was observed in each sample type. Phase contrast and fluorescent microscopic observations show that although MWCNTs are not toxic for human primary osteoblast cells, an intense interaction of the cells with MWCNTs reduces their proliferation and markedly affects their morphology.The synthesis and investigation of vertically aligned carbon nanotube (VACNT) based materials are gaining more-and-more interest among scientists due to their specific properties (e.g., electrical, optical, mechanical). Therefore, our interest for the present research has focused on synthesis of WO₃/VACNT based nanostructures (using carbon nanotube forests obtained by catalytic chemical vapor deposition-CCVD method on aluminum substrate) using different synthesis pathways and WO₃ precursors. The obtained composites were investigated by scanning electron microscopy (SEM), Raman spectroscopy, while the obtained crystal structures were characterized by X-ray diffraction (XRD). Results have shown that depending on the synthesis method, and using as template the carbonaceous structure, we can successfully obtain non-stochiometric tungsten oxide (W18O49) or WO₃ composites.