TS Science

Preparation of granular activated carbons from yellow mombin fruit stones for CO2 adsorption

Stones of yellow mombin, a native fruit of the tropical America and West Indies, were used as starting materials to produce activated carbons, subsequently used as adsorbent for CO2 capture. The carbonaceous materials were either chemically activated with HNO3, H3PO4 and KOH or physically activated with CO2. The carbon samples were characterized by SEM, EDX, TG/DTA...

Facile synthesis of nanostructured monoclinic bismuth vanadate by a co-precipitation method: Structural, optical and photocatalytic properties

We report the synthesis of bismuth vanadate (BiVO4) nanostructure by atoxic-free, inexpensive co-precipitation method. The BiVO4 nanostructures were derived from bismuth nitrate and ammonia metavanadate as starting precursors and sodium hydroxide (NaOH) were used as stabilizers for tuning the morphology (nanorod, nanospheriod and nanoparticulate). The influence of ...

The development of a highly conductive PEDOT system by doping with partially crystalline sulfated cellulose and its electric conductivity

Using direct sulfation of cellulose, we prepared sulfated cellulose (CS) with various degrees of substitution of sulfate groups (DS), which we used as dopants for PEDOT. PEDOT/CS were prepared via in situ chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) in an aqueous CS solution. Films of the obtained PEDOT/CS were formed using spin-coating. A...

Formation of amorphous calcium carbonate and its transformation into mesostructured calcite

Amorphous calcium carbonate (ACC) is a key precursor of crystalline CaCO3 biominerals and biomimetic materials. Despite recent extensive research, its formation and amorphous-to-crystalline transformation are not, however, fully understood. Here we show that hydrated ACC nanoparticles form after spinodal liquid?liquid phase separation and transform via dissolution/...

Selective nitrogen doping of graphene by energy-controlled neutral beam

Nitrogen-doped graphene potentially could be used in electronic devices, sensors, and energy-based devices. The bonding state between the carbon and nitrogen for each application plays an important role, e.g., the graphitic nitrogen has a high catalytic activity in fuel cell systems. However, it is still difficult to synthesize the bonding state selectivity. We con...

Simultaneous synthesis of vertically aligned carbon nanotubes and amorphous carbon thin films on stainless steel

Carbonaceous nanostructures such as carbon nanotubes, graphene and transparent carbon-based thin films are envisioned to be part of the next generation of electronic devices, mechanical structures, and energy-storage systems. To synthesize these nanostructures on a large scale by chemical vapor deposition, large-area, flexible substrates are needed. Here, we studie...

Li+ solvation in glyme?Li salt solvate ionic liquids

Certain molten complexes of Li salts and solvents can be regarded as ionic liquids. In this study, the local structure of Li+ ions in equimolar mixtures ([Li(glyme)]X) of glymes (G3: triglyme and G4: tetraglyme) and Li salts (LiX: lithium bis(trifluoromethanesulfonyl)amide (Li[TFSA]), lithium bis(pentafluoroethanesulfonyl)amide (Li[BETI]), lithium trifluoromethanes...

Synthesis of refractory conductive niobium carbide nanowires within the inner space of carbon nanotube templates

Conductive niobium carbide (NbC) nanowires with diameters of 1–3 nm were synthesized within the inner space of carbon nanotubes (CNTs) by exposing the CNTs to niobium (V) chloride vapor through hydrogen reduction. The NbC nanowires were found to have a NaCl-type crystal structure by transmission electron microscopy and transmission electron diffractometry. Re...

Green synthesis of aniline by phosphorus-doped titanium dioxide polymorphs

Phosphor doping in association with a heterostructure not only modifies the band structure of titanium dioxide (TiO2) to make it more responsive to visible light, but it also suppresses its charge recombination and causes TiO2 to have enhanced photoactivity. In this paper, we report on the controlled synthesis of phosphor-doped binary and ternary TiO2 nanostructure...

Influence of ozone on N-doped multi-walled carbon nanotubes

Nitrogen-doped multi-walled carbon nanotubes (N-MWCNT) were selectively grown on oxidised silicon substrate by means of catalytic chemical vapour deposition with decomposition of acetonitrile in the presence of ferrocene (FeCp2) at 900°C. The synthesised N-MWCNT film was initially treated with continuous ozone flow for various time periods and characterised by ...

Green synthesis of methanol by photocatalytic reduction of CO2 under visible light using a graphene and tourmaline co-doped titania nanocomposites

In this work, we studied the effect of tourmaline percent on the photocatalytic activity of mesoporous TiO2–graphene. To evaluate and compare the physical properties of the prepared materials, X-ray diffraction analysis, BET measurements, UV–vis spectroscopy, PL spectroscopy, and TEM were applied. To determine the photocatalytic efficiency of the prepar...

Biphase TiO2 Microspheres with Enhanced Photocatalytic Activity

TiO2 microspheres (TMS) with perfect spherical morphology were synthesized by spray drying of a hydrothermally cured aqueous suspension of TiO2 nanoparticles. TiO2 powders (TP) obtained by drying the nanoparticle suspension were studied simultaneously to determine which was the most efficient photocatalyst. SEM images and laser granulometry on TMS show spherical mo...

Chiral self-assembly of enantiomerically pure (4S,7R)-campho[2,3-c]pyrazole in the solid state: a vibrational circular dichroism (VCD) and computational study

Ex situ Raman mapping study of mechanism of cordierite formation from stoichiometric oxide precursors

Ex situ Raman spectroscopy and Raman mapping showed that at temperatures below 1300 °C, magnesia reacted with either alumina or silica to form magnesium aluminate (spinel) or magnesium silicate. At 1300 °C or higher, the reaction between magnesium silicate and alumina, or spinel and silica, led to cordierite formation. Moreover, the presence of silica and s...

Zinc Induces Apatite and Scholzite Formation during Dentin Remineralization

The aim of this study was to ascertain whether zinc may improve the repair ability of demineralized dentin. Dentin disks were demineralized by phosphoric acid during 15 s and immersed in artificial saliva, remineralizing solution, a zinc chloride solution and a zinc oxide solution. Dentin specimens were analyzed after 24 h and 1 month of storage. Surface morphology...