Alkanephosphonic Acids Research Articles

“Nickel Nanoflowers” with Surface-Attached Fluoropolymer Networks by C,H Insertion for the Generation of Metallic Superhydrophobic Surfaces

Metallic superhydrophobic surfaces (SHSs) combine the attractive properties of metals, such as ductility, hardness, and conductivity, with the favorable wetting properties of nanostructured surfaces. Moreover, they promise additional benefits with respect to corrosion protection. For the modification of the intrinsically polar and hydrophilic surfaces of metals, a new method has been developed to deposit a long-term stable, highly hydrophobic coating, using nanostructured Ni surfaces as an example. Such substrates were chosen because the deposition of a thin Ni layer is a common choice for enhancing corrosion resistance of other metals. As the hydrophobic coating, we propose a thin film of an extremely hydrophobic fluoropolymer network. To form this network, a thin layer of a fluoropolymer precursor is deposited on the Ni substrate which includes a comonomer that is capable of C,H insertion cross-linking (CHic). Upon UV irradiation or heating, the cross-linker units become activated and the thin glassy film of the precursor is transformed into a polymer network that coats the surface conformally and permanently, as shown by extensive extraction experiments. To achieve an even higher stability, the same precursor film can also be transformed into a chemically surface-attached network by depositing a self-assembled monolayer of an alkane phosphonic acid on the Ni before coating with the precursor. During cross-linking, by the same chemical process, the growing polymer network will simultaneously attach to the alkane phosphonic acid layer at the surface of the metal. This strategy has been used to turn fractal Ni "nanoflower" surfaces grown by anisotropic electroplating into SHSs. The wetting characteristics of the obtained nanostructured metallic surfaces are studied. Additionally, the corrosion protection effect and the significant mechanical durability are demonstrated.

Electrochemical Investigation of Chemical Lift-off Lithography on Au and ITO

Chemical lift-off lithography (CLL) on Au and indium tin oxide (ITO) were investigated using electrochemical methods in terms of the coverage, stability, and substrate-dependence. Self-assembled monolayers (SAMs) of 11-mercaptoundecanol (MUO) on Au and hydroxyundecylphosphonic acid (HUPA) on ITO were patterned by an oxygen plasma-activated PDMS stamp. Siloxyl groups (SiOH) from the activated PDMS formed covalent bonds with the hydroxyl groups of the SAM (OH) on the Au and ITO substrate, which enables the detachment of the SAM molecules from the surface, called CLL. The interfacial properties of the SAM-modified electrodes and post-CLL electrodes were investigated with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results revealed that ca. 78% of the SAM on Au is detached by CLL and the remaining SAM is stable during subsequent SAM formations. For alkanephosphonic acid on ITO, ca. 57% of the SAM was removed in terms of electrochemistry indicating the dependence of CLL on the anchoring groups. AFM images show the pattern formation by CLL on both Au and ITO.

Fluorophosphonate-functionalised titanium via a pre-adsorbed alkane phosphonic acid: a novel dual action surface finish for bone regenerative applications

Enhancing vitamin D-induced human osteoblast (hOB) maturation at bone biomaterial surfaces is likely to improve prosthesis integration with resultant reductions in the need for revision arthroplasty consequent to aseptic loosening. Biomaterials that are less appealing to microorganisms implicated in implant failures through infection are also highly desirable. However, finding surfaces that enhance hOB maturation to active vitamin D yet deter bacteria remain elusive. In addressing this, we have sought to bio-functionalise titanium (Ti) with lysophosphatidic acid (LPA) and related, phosphatase-resistant, LPA analogues. The impetus for this follows our discovery that LPA co-operates with active vitamin D3 metabolites to secure hOB maturation in vitro including cells grown upon Ti. LPA has also been found, by others, to inhibit virulence factor production and biofilm formation of the human opportunistic pathogen Pseudomonas aeruginosa. Collectively, selected LPA species might offer potential dual-action surface finishes for contemporary bone biomaterials. In attaching a phosphatase-resistant LPA analogue to Ti we took advantage of the affinity of alkane phosphonic acids for TiO2. Herein, we provide evidence for the facile development of a dual-action Ti surface for potential orthopaedic and dental applications. Successful conjugation of an LPA analogue (3S)1-fluoro-3-hydroxy-4-(oleoyloxy)butyl-1-phosphonate (FHBP) to the Ti surface was supported through physiochemical characterisation using x-ray photoelectron spectroscopy and secondary ion mass spectrometry. hOB maturation to active vitamin D3 was enhanced for cells grown on FHBP-Ti whilst these same surfaces exhibited clear antiadherent properties towards a clinical isolate of Staphylococcus aureus.

Controlling the assembly of CdS nanorods via solvent and acidity.

We report control over the phase behavior of CdS nanorods via the solvent and acidity. CdS nanorods were synthesized using alkane phosphonic acid ligands, which were replaced after synthesis by a series of aromatic ligands. Change of ligand enabled us to cast films from different solvents. By replacing toluene with ethanol or water the rod-rod interactions dominate over rod-substrate interactions, thereby favoring simple hexagonal ordering (2D). When dispersed in water, a net electrostatic charge on the nanorods could be induced by deprotonating the ligands at high pH. This net charge favors 2D nematic ordering over homeotropic ordering of the nanorods on a substrate. A calculation of the van der Waals and electrostatic interactions is presented that explains the observed influence of solvent and pH.

Characterizing the Molecular Order of Phosphonic Acid Self-Assembled Monolayers on Indium Tin Oxide Surfaces

Self-assembled monolayers (SAMs) of alkanephosphonic acids with chain lengths between 8 and 18 carbon units were formed on thin films of indium tin oxide (ITO) sputter-deposited on silicon substrates with 400 nm thermally grown SiO(2). The silicon substrates, while not intended for use in near-IR or visible optics applications, do provide smooth surfaces that permit systematic engineering of grain size and surface roughness as a function of the sputter pressure. Argon sputter pressures from 4 to 20 mTorr show systematic changes in surface morphology ranging from smooth, micrometer-sized grain structures to <50 nm grains with 3× higher surface roughness. Near-edge X-ray absorption fine structure (NEXAFS) spectroscopy experiments are conducted for alkanephosphonic acids deposited on these wide range of ITO surfaces to evaluate the effects of these morphological features on monolayer ordering. Results indicate that long-chain SAMs are more highly ordered, and have a smaller tilt angle, than short-chain SAMs. Surprisingly, the 1-octadecyl phosphonic acids maintain their order as the lateral grain dimensions of the ITO surface shrink to ∼50 nm. It is only when the ITO surface roughness becomes greater than the SAM chain length (∼15 Å) that SAMs are observed to become relatively disordered.

A Novel Synthesis of 1-Aminoalkanephosphonic Acid Derivatives from 1-(N-Acylamino)- alkyltriphenylphosphonium Salts

Efficient and convenient procedures for the α-amidoalkylation of trialkylphosphites with 1-(N-acylamino)alkyltriphenylphosphonium salts followed by a Michaelis–Arbuzov-type reaction to afford 1-(N-acylamino)alkanephosphonic acid esters have been developed. High yields and simple isolation and purification protocols are the main advantages of this method.

Nanotribological Properties of Alkanephosphonic Acid Self-Assembled Monolayers on Aluminum Oxide: Effects of Fluorination and Substrate Crystallinity

Two phosphonic acid (PA) self-assembled monolayers (SAMs) are studied on three aluminum oxide surfaces: the C and R crystallographic planes of single crystal alpha-alumina (sapphire) and an amorphous vapor-deposited alumina thin film. SAMs are either fully hydrogenated CH3(CH2)17PO3H2 or semifluorinated CF3(CF2)7(CH2)11PO3H2. Atomic force microscope (AFM) topographic imaging reveals that the deposited films are homogeneous, atomically smooth, and stable for months in the laboratory environment. Static and advancing contact angle measurements agree with previous work on identical or similar films, but receding measurements suggest reduced coverage here. To enable reproducible nanotribology measurements with the AFM, a scanning protocol is developed that leads to a stable configuration of the silicon tip. Adhesion for the semifluorinated films is either comparable to or lower than that for the hydrogenated films, with a dependence on contact history observed. Friction between each film and the tips depends strongly upon the type of molecule, with the fluorinated species exhibiting substantially higher friction. Subtle but reproducible differences in friction are observed for a given SAM depending on the substrate, revealing differences in packing density for the SAMs on the different substrates. Friction is seen to increase linearly with load, a consequence of the tip's penetration into the monolayer.

FABRICATION OF PATTERNED ELECTROLUMINESCENT POLYMERS WITH MICROCONTACT PRINTING

For most practical applications, it is essential to fabricate micro- or nano-scale polymer electroluminescent (EL) devices and pixel arrays. Microcontact printing, which uses a patterned elastomer (usually PDMS) as the mold to generate or transfer the pattern offers immediate advantages. Here we describe a method of patterning polymeric EL materials based on microcontact printing using PDMS mold. In this technique, we use the self-assembled monolayer (SAM) system of alkanephosphonic acids on ITO substrate, and patterned EL polymer is formed on the SAM-modified ITO substrate.

Effects of Fluorination on Self-Assembled Monolayer Formation from Alkanephosphonic Acids on Aluminum: Kinetics and Structure

We have used infrared spectroscopy, ellipsometry, and contact angle measurements to study self-assembled monolayer (SAM) formation on aluminum native oxide from three alkanephosphonic acids: CF3(CF2)7(CH2)11PO3H2 (F8H11PA), and CH3(CH2)nPO3H2 (n = 15 (H16PA); n = 21 (H22PA)). These compounds show significant differences in film structure and film formation kinetics. Strikingly, the methylene segment of the semifluorinated F8H11PA SAM never reaches an ordered state even at long assembly times. This contrasts with the ordered chains in equilibrium films from H16PA and H22PA. We attribute this behavior to steric effects of the fluorocarbon segment and the phosphonic acid headgroup. F8H11PA represents an amphiphile in which bulky head and tail groups prevent an interposed hydrocarbon segment from ordering. For all three phosphonic acids, negative peaks attributed to loss of Al−OH groups in the infrared spectra of the monolayers are consistent with a condensation reaction between the acids and surface hydroxy...

Patterning Indium Tin Oxide and Indium Zinc Oxide Using Microcontact Printing and Wet Etching

We report a procedure that uses microcontact printing and wet chemical etching to fabricate patterned films of indium tin oxide (ITO) and indium zinc oxide (IZO). The procedure consists of three steps: (1) inking a patterned elastomeric stamp with an alkanephosphonic acid; (2) microcontact printing to form a patterned multilayer film of alkanephosphonic acid on the surface of an ITO or IZO film; (3) etching the unprotected regions of the ITO or IZO film using 0.05 M oxalic acid as the etchant. We demonstrate this procedure by fabricating patterned ITO and IZO films with areas as large as 15 cm2 and minimum feature sizes of ∼2 μm. The key step in this procedure is applying the alkanephosphonic acid ink to the surface of the stamp. We present two different inking methods to illustrate the impact of stamp inking on the quality of printed and etched ITO and IZO films.

Self-Assembly and Bonding of Alkanephosphonic Acids on the Native Oxide Surface of Titanium

Alkanephosphonic acids assemble from solution on the native oxide surface of titanium to form alkane chain ordered films which, however, are easily removed by solvent rinse. In contrast, assembling the alkanephosphonic acid from solution on the native oxide surface of titanium followed by gentle heating gives an alkane chain ordered film of the acid which is strongly surface-bound; this film resists removal by solvent washing or simple mechanical peel testing. Surface imaging by atomic force microscopy shows comprehensive surface coverage by aggregated islands, with elevations of each consistent with monolayer formation. ω-Carboxyalkanephosphonic acids are also easily bound to the native oxide surface of Ti through self-assembly/heating. Infrared analysis is consistent with surface attachment through the phosphonate headgroup.

Phosphites Add Across Double Bonds

From the ACS meeting Chemists in Japan have developed a technique for the catalytic addition of hydrogen-phosphorus bonds (hydrophosphorylation) to olefins and conjugated dienes. Their achievement makes possible the convenient production of alkanephosphonic acid derivatives for potential use as synthetic intermediates, flame retardants, herbicides, chiral ligands (for asymmetric synthetic catalysts), and extraction media (to treat actinide nuclear waste). Hydrophosphorylation thus joins hydroboration and hydrosilylation as a means of forming bonds from carbon to other elements. The work was carried out by postdoctoral fellow Farzad Mirzaei, organic chemistry department chairman Masato Tanaka, senior research chemist Li-Biao Han, and postdoctoral fellow Chang-Qiu Zhao at the National Institute of Materials & Chemical Research, Tsukuba, Japan. Mirzaei reported the group's progress in a presentation to the Division of Organic Chemistry. The researchers find that success depends on the use of the cyclic ester...

Underpotentially Deposited Copper Promotes Self-Assembly of Alkanephosphonate Monolayers on Gold Substrates

Gold surfaces that had been previously modified electrochemically by the underpotential deposition (upd) of a monolayer of copper adsorb alkanephosphonic acids from solution to form oriented monolayers. While bare gold surfaces do not adsorb alkanephosphonic acids, a layer of copper at less than a monolayer is sufficient to alter the chemisorptive properties of the gold substrate. Octadecanephosphonic acid forms oriented oleophobic monolayers on the Au/Cu(upd) surface that are stable in both polar and nonpolar solvents. The alkanephosphonate films on Au/Cu(upd) are less densely packed than those that form on copper, but the Au/Cu(upd) substrate offers greater tolerance against oxidation and greater convenience of use. Electroactive monolayers can be formed on Au/Cu(upd) using 11-ferrocenylundecanephosphonic acid, where the assembled films exhibit the reversible electrochemical signature of the ferrocenyl group and a surface coverage of ∼4.0 × 10-10 mol/cm2.

Enhanced Bonding of Alkanephosphonic Acids to Oxidized Titanium Using Surface-Bound Alkoxyzirconium Complex Interfaces

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTEnhanced Bonding of Alkanephosphonic Acids to Oxidized Titanium Using Surface-Bound Alkoxyzirconium Complex InterfacesEllen S. Gawalt, Gang Lu, Steven L. Bernasek, and Jeffrey SchwartzView Author Information Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009 Cite this: Langmuir 1999, 15, 26, 8929–8933Publication Date (Web):October 7, 1999Publication History Received12 July 1999Published online7 October 1999Published inissue 1 December 1999https://doi.org/10.1021/la990906mCopyright © 1999 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views939Altmetric-Citations92LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (78 KB) Get e-AlertsSUBJECTS:Deposition,Organophosphorus compounds,Oxides,Pretreatment,Thin films Get e-Alerts

Microcontact Printing of Alkanephosphonic Acids on Aluminum: Pattern Transfer by Wet Chemical Etching

Microcontact printing (μCP) has been used to pattern octadecanephosphonic acid on the native oxide surface film of aluminum supported on silicon or on silicon nitride-coated silicon wafers. The patterned alkanephosphonic acid protects the Al2O3/Al film from etching in a solution containing phosphoric, acetic, and nitric acids and water in a ratio of 16:1:1:2 and allows the nonpatterned film to be removed selectively. The patterned Al2O3/Al structures resulting from etching are continuous and electrically conductive within each pattern, and separated patterns are electrically isolated. Resistance measurements of the patterned structures are presented. Using μCP, Schottky diodes of aluminum have been prepared on p-type Si(100). The Schottky diodes exhibit rectifying behavior, and the forward-bias current−voltage (I−V) and reverse-bias capacitance−voltage (C−V) characteristics are presented.

Polarographic Investigations of Functionalized Alkanephosphonic Acids. Part II

Polarographic Investigations of Functionalized Alkanephosphonic Acids. Part II

ChemInform Abstract: Synthesis of 1‐Methyl‐1‐(N‐substituted carbamoyl‐ and thiocarbamoyl‐ amino)alkanephosphonic Acid Diethyl Esters.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

SYNTHESIS OF 1-METHYL-1-(N-SUBSTITUTED CARBAMOYL- AND THIOCARBAMOYL-AMINO) ALKANEPHOSPHONIC ACIDS-DIETHYL ESTERS

Abstract Diethylesters of 1-methyl-1-(N-substituted carbamoyl- or thiocarbamoyl-amino)-alkane-phosphonic acids are obtained by interaction of O,O-diethyl esters of 1-amino-1-methyl-alkanephosphonic acids and different isocyanates or isothiocyanates at room temperature. Cyclization of 1-methyl-I-(N-butylcarbamoyl-amino)-ethanephosphonic acid diethyl ester to 3-butyl-5,5,-dimethyl-2,4-dioxo-4-hydroxy-1,3,4-diazaphosphole is achieved.

Salting-out chromatography—VIII : Analysis of mixtures of monoalkyl esters of alkane-phosphonic acids and dialkyl esters of phosphoric acid

A method is described for the determination of each compound in a mixture of 19 acids of phosphorus.

Salting-out chromatography—VII: Analysis of mixtures of dialkylphosphoric acids, alkanephosphonic acids, and orthophosphoric acid

Attempted separations of several phosphorus acids by gas-partition and anion-cxchange chromatography were unsuccessful. This paper describes a quantitative method of separation by salting-out chromatography on special Dowex 50-X4 resins of low capacity.