Formation of nanoparticulate iron(III) oxide-stearate multilayer through Langmuir-Blodgett method

Abstract

tional energy at the T site is 145 meV in the present calculation and 152 meV in the zeroth-order approximation. The energy at the 0 site is 43 meV in the present calculation and 86 meV in the zeroth-order approximation. By the inelastic neutron scattering measurements the vibrational energy of hydrogen in the bulk a-zirconium at 873 K was obtained to be 144 meV, and the energy spread (fwhm of the peak) is 47 meVn2' It has been found that the calculated vibrational energy at the T site is in good agreement with the experiment. Garrett measured the vibrational energy of hydrogen on Ti(0001) surface by using high-resolution electron energy loss spectroscopy (HREELS).2S The vibrational energy of H and D is reported to be 120 and 85 meV, respectively. This value is greater than that calculated for hydrogen on zirconium surface. We cannot differentiate that this is due to the difference between Ti and Zr or the uncertainty of this calculation. (25) Garrett, S. J.; Egdell, R. G.; Riviere, J. C. J . Electron Spectrosc.Stable nanoparticulate a-Fe203stearate (Fe203-St) monolayers can be obtained by using nanoparticulate a-Fe203 (diameter 70 A) as the subphase. The area extrapolated to r = 0 is 27 A2 per hydrocarbon chain of the monolayer. The "collapse" pressure is about 28 dynlcm. The transfer ratio is 1.0 f 0.1 (this is a constant within the limit of experiment). The long spacing of the multilayer determined by X-ray diffraction is 160 A. The tilt angle of the hydrocarbon chains revealed by IR is 31° f 5 O . The long CH2 sequence of the hydrocarbon chains of the multilayer is in a trans planar structure. The surface coverage by Fez03 nanoparticles is very large (more than 90%). Stearic acid is converted to stearate ion almost completely and chemical bonds were formed between Fez03 and stearate ions. The particles in the polar plane of the multilayer are close packed in a hexagonal close packed (hcp) bilayer structure. The total thickness of the multilayer can be several thousand angstroms or more. The absorption and transmission properties of isolated nanoparticulate Fe203 hydrosol were maintained. Thus the multilayer can be regarded as a three-dimensional superlattice of quantum size particles.

Chemical One Step Method to Prepare Polyaniline Nanofibers with Electromagnetic Function

“…For example, the C --C stretching deformation of the quinoid (1 562 cm À1 ) and benzenoid rings (1 479 cm À1 ), the C-N stretching of the secondary aromatic amine (1 293 cm À1 ), the aromatic C-H in-plane bending (1 116 cm À1 ), and the out-of-plane deformation of C-H in the 1,4-disubstituted benzene ring (802 and 508 cm À1 ) are observed. [14] The UV-vis absorption spectra of the composite nanofibers dissolved in de-ionized water further proved this result ( Figure 2 [3] ). For example, two peaks at 440 and 900 nm with a long tail, which are assigned to polaron bands, are observed, [15] indicating that the composite nanofibers are identical to the emeraldine salt form of PANI.…”

“…[3] Up to date, polyaniline (PANI) nanotubes containing Fe 3 O 4 nanoparticles (%10 nm in diameter) has been firstly prepared by a template-free method in the presence of Fe 3 O 4 nanoparticles. [4] The magnetic nanoparticles in that method are co-structured with oxidation polymerization of aniline to form the PANI/Fe 3 O 4 nanotubes via a self-assembly process.…”

Polyaniline matrix containing nickel ferromagnet

“…[4][5][6][7][8][9] In fact, composites of conducting polymers containing magnetic particles have many potential applications in electromagnetic interference shielding, 10 electrochromic devices, 11 and nonlinear optical systems. 12 Until now, many studies on composites with electromagnetic properties have been reported. Yoneyama et al 13 and Partch et al, 14 for example, reported the incorporation of metal oxide particles into polypyrrole during electropolymerization.…”

Interfacially formed organized planar inorganic, polymeric and composite nanostructures

“…LB technique has proved to be an efficient tool for fabrication of organized interfacial two-dimensional arrays of proteins [156,157], ligand-stabilized inorganic nanoclusters [158][159][160], nanoparticles [161][162][163][164][165][166][167][168][169][170][171][172][173][174][175], BaCrO 4 nanorods [85], metal and semiconductor nanowires [83,84] and carbon nanotubes [176] as well as corresponding multilayer structures. Nanoparticulate LB films were used to form patterned structures on surfaces [177] via bsoft lithographyQ approach introduced by Zhao et al [178] at Harvard.…”