Characterization of the monolayer as the basis of Langmuir-Blodgett film formation: metal derivatives of behenic acid

Bettarini, Silvia; Bonosi, Francesca; Gabrielli, G.; Martini, Giacomo

doi:10.1021/la00054a010

Cited by 24 publications

(14 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…34 The dimer structure is postulated to be responsible for the expanded isotherms and poor transfer characteristics of the carboxylate Langmuir monolayer on the copper(II)-containing subphase. 20,35 The association of copper ions with the carboxylic group to form copper arachidate is supported by the film's morphological change in this case.…”

mentioning

confidence: 64%

Synthesis of Copper Sulfide Nanorod Arrays on Molecular Templates

et al. 2004

View full text Add to dashboard Cite

We investigate the making of semiconductor nanorods using well-defined molecular templates. The films are characterized by AFM and XPS. The spin-coated monolayer of arachidic acid assembles on graphite as 1D nanostripes with bilayer periodicity. The copper arachidate film shows curved stripes, which become straight after reacting with hydrogen sulfide. The new template scheme may facilitate the fabrication of nanorod arrays of a variety of inorganic and semiconducting materials.Metal and semiconductor nanorods are the potential building blocks for self-assembled nanoscale electronic circuits and energy-conversion devices. 1-3 The spatial assembly of such nanorods is not only necessary for making functional devices but also presents an opportunity to explore novel collective properties. One strategy in arranging nanoblocks into ordered arrays is the template-directed synthesis in which guest molecules are deposited or react according to the spatial registry of host patterns and lattices. 4-6 This letter describes a new concept of nanorod array synthesis on self-assembled molecular templates. Long-chain alkanes and their derivatives, such as fatty acids, self-assemble on graphite to form a highly ordered 1D stripe phase because of the 1D epitaxy between the zigzag chain length of 1,3 methylene groups () 0.251 nm) and the distance of the next nearest neighbor of the graphite lattice () 0.246 nm). 7,8,9 The template-directed synthesis strategy is demonstrated here by the fabrication of copper sulfide nanorod arrays on arachidic acid monolayers. The synthesis scheme is described in Figure 1. Copper ions embedded in the carboxylic stripes of 1-nm width serve as precursors to copper sulfide nanorod formation. The aliphatic stripes of 4-nm width spatially separate the copper sulfide nanorods.Copper sulfide is an interesting material for its metal-like electrical conductivity, 10 chemical-sensing capability, 11 and ideal characteristics for solar energy absorption. 12 Metal sulfide nanoparticle thin films of up to 5-nm thickness have been synthesized under Langmuir monolayers and in Langmuir-Blodgett (LB) multilayers by exposing fatty acid and metal ion complexes to a hydrogen sulfide atmosphere. [13][14][15][16] In addition to synthesizing copper sulfide in the LB films, 17-22 copper sulfide nanoparticles and nanowires have been synthesized by other methods, such as microemulsions, 23 vesicles, 24 solid crystals, 25 electrochemistry, 26 an organic-assisted hydrothermal process, 27 and thermolysis. 28,29 The method described here offers several promising advantages over other methods: (1) the choice for pattern-forming amphiphiles is essentially unlimited; (2) spin coating is a simple yet controllable film-deposition method; (3) diverse surface chemistry and physics can be studied on well-defined nanoscale patches; and (4) the nanostructures are ideally suited for surface-scanning techniques such as atomic force microscopy (AFM).The thickness, uniformity, and spatial order of spin-coated films can be controlled by the con...

show abstract

mentioning

confidence: 64%

Synthesis of Copper Sulfide Nanorod Arrays on Molecular Templates

et al. 2004

View full text Add to dashboard Cite

show abstract

“…The interaction between the film-forming molecules and the domains, respectively, is noticable already at relatively low surface densities. Bettarini et al . concluded from ESR studies of collapsed copper−docosanoate monolayers that dimeric Cu−Cu units may be responsible for some noteworthy effects of this system, including expansion and hysteresis characteristics as well as poor LB transferability.…”

Section: Discussionmentioning

confidence: 99%

Effect of Bivalent Ba, Cu, Ni, and Zn Cations on the Structure of Octadecanoic Acid Monolayers at the Air−Water Interface As Determined by External Infrared Reflection−Absorption Spectroscopy

1996

View full text Add to dashboard Cite

Infrared reflection−absorption spectroscopic (IRRAS) measurements of octadecanoic acid monolayers on aqueous subphases containing 1 mM BaCl2, CuCl2, NiCl2, and ZnCl2, respectively, supplied insight into the molecular order and the coordination complexes of the system alkanoic acid/bivalent cation. The formation of highly ordered crystalline domains already at large areas per molecule is reflected by antisymmetric methylene stretching vibrations which are independent of the compression status, however, cation-dependent (Ba2+, Ni2+, ∼2917 cm-1; Cu2+, 2916.1 cm-1; Zn2+, unusually low, 2914.3 cm-1). The analysis of the antisymmetric and symmetric carboxylate stretching vibrations allowed the determination of coordination types of the respective alkanoic acid/cation system, while from the methylene scissoring vibration the subcell structure could be inferred in most cases. Ba2+ cations form an ionic alkanoate, the chain packing of which appears to be mainly orthorhombic. For Cu2+ cations both bridging bidentate and chelating bidentate complexes were found, and the chain packing is hexagonal. Ni2+ cations appear to show both monodentate and ionic complex formation, while for Zn2+ cations a single species was observed which is assigned to an unsymmetric chelating bidentate complex and a triclinic chain packing. Furthermore, the carboxylate and methylene scissoring bands allowed elucidation of the transformation mechanism that is encountered upon successive in situ acidification of the octadecanoic acid monolayer/Zn2+ system: in addition to the unsymmetric chelating bidentate complex (triclinic) encountered at pH 6.7, an ionic interaction becomes increasingly evident between pH 6.1 and 5.55, and eventually at pH 5.0 the free alkanoic acid (orthorhombic?) is the dominant species.

show abstract

“…The temperature (20 ~ was controlled with the Haake FK thermostat with an accuracy up to 0.01 ~ The plurilayers on germanium ATR plates were prepared and transferred [4] by the LB method by means of a KSV LB 5000 balance.…”

Section: -E X P E R I M E N T a Lmentioning

confidence: 99%

Monolayers of proteins: β-lactoglobulin and its interactions with phospholipids

et al. 1994

View full text Add to dashboard Cite

Summary. --Monolayers of a protein ~-lactoglobulin (~L) and two lipids distearoylphosphatidylcholine (DSPC) and dimirystoylphosphatidylcholine (DMPC) on aqueous subphase containing Na § or Ca 2+ ions are studied. The spreading isotherms and the ATR-FTIR spectra of LB plurilayers transferred, allow to deduce that a-helix conformation of ~-lactoglobulin is the prevailing form. The study of bidimensional mixtures between ~L with DSPC and with DMPC shows that the components are incompatible at the W/A interface. PACS 68.35.Md -Surface energy; thermodynamic properties. PACS 01.30.Cc -Conference proceedings. -I n t r o d u c t i o n .Bidimensional systems of amphiphiles represent a useful model for biological membranes.In particular, mixed monolayers of proteins and lipids represent the single monolayer of natural membranes. Besides these monolayers are well defined either by thermodynamic quantities or by the investigation of the molecular distribution and energies, and therefore constitute a useful way to study the orientation and interaction in cellular bilayers.In previous works, mixed films of lipids and polipeptides and of different polipeptidic substances were studied [1].To improve the representativity of monolayer model, a study of mixed monolayers of a protein ~-lactoglobulin (~L) with phospholipids with different length of the hydrophobic chains is reported.

show abstract

Characterization of the monolayer as the basis of Langmuir-Blodgett film formation: metal derivatives of behenic acid

Cited by 24 publications

References 0 publications

Synthesis of Copper Sulfide Nanorod Arrays on Molecular Templates

Synthesis of Copper Sulfide Nanorod Arrays on Molecular Templates

Effect of Bivalent Ba, Cu, Ni, and Zn Cations on the Structure of Octadecanoic Acid Monolayers at the Air−Water Interface As Determined by External Infrared Reflection−Absorption Spectroscopy

Monolayers of proteins: β-lactoglobulin and its interactions with phospholipids

Contact Info

Product

Resources

About