Surface passivation dictated site-selective growth of aligned carbon nanotubes.

Surface defects play a significant role in the nucleation and growth of metal particles. Site-selective nucleation of metal catalyst particles, and the subsequent growth of nanostructures, could thus be accomplished by defect engineering. This paper demonstrates the switching of growth sites of vertically aligned multiwall carbon nanotubes (MW-CNTs) by manipulation of surface passivation of the substrate and discusses the possible mechanism behind this selectivity.

Influence of chemical potential on shape evolution of 2D-MoS flakes produced by chemical vapor deposition.

High-quality, ultrathin 2D-MoS layers with large area were grown on SiO/Si substrates by using atmospheric pressure chemical vapor deposition (APCVD) at elevated temperatures. The growth precursors (MoO and S) were placed separately inside the double-zone furnace to control the growth parameters individually for better flexibility in the growth process. In this study, it was found that the shape and edge structure of the evolved MoS flakes were significantly influenced by the chemical potential of the Mo and S precursor concentration.

Influence of chemical potential on shape evolution of 2D-MoSflakes produced by chemical vapor deposition.

High-quality, ultrathin 2D- MoS2 layers with large area were grown on SiO2/Si substrates by using chemical vapor deposition (CVD) at elevated temperatures. The growth precursors (MoO3 and S) were placed separately inside the double zone furnace to control the growth parameters individually for better flexibility in the growth process. In this study, it was found that the shape and edge structure of the evolved MoS2 flakes were significantly influenced by the chemical potential of the Mo and S precursor concentration.

A napthelene-pyrazol conjugate: Al(III) ion-selective blue shifting chemosensor applicable as biomarker in aqueous solution.

A newly synthesized and crystalographically characterized napthelene–pyrazol conjugate, 1-[(5-phenyl-1H-pyrazole-3-ylimino)-methyl]-naphthalen-2-ol (HL) behaves as an Al(III) ion-selective chemosensor through internal charge transfer (ICT)-chelation-enhanced fluorescence (CHEF) processes in 100 mM HEPES buffer (water–DMSO 5:1, v/v) at biological pH with almost no interference of other competitive ions. This mechanism is readily studied from electronic, fluorimetric and (1)H NMR titration. The probe (HL) behaved as a highly selective fluorescent sensor for Al(III) ions as low as 31.

Cell permeable fluorescent receptor for detection of H2PO4(-) in aqueous solvent.

A new colorimetric fluorescent receptor for H(2)PO(4)(-) is reported in this communication. The receptor can detect dihydrogen phosphates optically by developing a color change from yellow to green. Acute spectral responses to H(2)PO(4)(-) in HEPES buffer (DMSO-HEPES 1:9) have been observed.

A water soluble Al3+ selective colorimetric and fluorescent turn-on chemosensor and its application in living cell imaging.

An efficient water soluble fluorescent Al(3+) receptor, 1-[[(2-furanylmethyl)imino]methyl]-2-naphthol (1-H) was synthesized and characterized by physico-chemical and spectroscopic tools along with single crystal X-ray crystallography. High selectivity and affinity of 1-H towards Al(3+) in HEPES buffer (DMSO/water: 1/100) of pH 7.4 at 25 °C showed it to be suitable for detection of intracellular Al(3+) by fluorescence microscopy.

A ratiometric fluorescent chemosensor for iron: discrimination of Fe2+ and Fe3+ and living cell application.

A newly designed probe, 6-thiophen-2-yl-5,6-dihydrobenzo[4,5]imidazo-[1,2-c] quinazoline (HL(1)) behaves as a highly selective ratiometric fluorescent sensor for Fe(2+) at pH 4.0-5.0 and Fe(3+) at pH 6.

Development of a highly selective cell-permeable ratiometric fluorescent chemosensor for oxorhenium(V) ion.

A novel 6-(2-pyridinyl)-5,6-dihydrobenzimidazo[1,2-c]quinazoline (HL) serves as a first-time highly selective and sensitive ratiometric fluorescent chemosensor probe for oxorhenium (ReO(V)) ion in acetonitrile : water = 9 : 1 (v/v) at 25 °C. The decrease in fluorescence at 410 nm and increase in fluorescence at 478 nm with an isoemissive point at 444 nm in the presence of ReO(V) ion is accounted for by the formation of mononuclear [ReOL(2)Cl] complex, characterized by physico-chemical and spectroscopic tools. The fluorescence quantum yield of the chemosensor (HL) was only 0.

A new half-condensed Schiff base compound: highly selective and sensitive pH-responsive fluorescent sensor.

A new probe, 3-[(3-benzyloxypyridin-2-ylimino)methyl]-2-hydroxy-5-methylbenzaldehyde (1-H) behaves as a highly selective fluorescent pH sensor in a Britton-Robinson buffer at 25 °C. The pH titrations show a 250-fold increase in fluorescence intensity within the pH range of 4.2 to 8.