Conjugated Polymer Network Ultrathin Films on Metal Interfaces using the Precursor Polymer Approach: Design, Synthesis and In-situ Characterization

2002 ◽  
Vol 734 ◽  
Author(s):  
Rigoberto Advincula ◽  
Chuanjun Xia ◽  
Prasad Taranekar ◽  
Ken Onishi ◽  
Suxiang Deng ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Ultrathin Films ◽  
Polymer Network ◽  
Dielectric Materials ◽  
Design Synthesis ◽  
Metal Oxide Surfaces ◽  
Lithographic Patterning ◽  
Precursor Polymer ◽  
Electrochemical Approach

ABSTRACTWe have reported recently a novel method for cross-linking conjugated polymers involving a “precursor polymer” route, where the electrochemical method can be used to prepare ultrathin films on conducting metal and metal oxide surfaces. In this paper, we present the design, synthesis, protocol, and recent results in the application of these thin film materials. An emphasis will be given on how these films are characterized in-situ by a combined surface plasmon spectroscopy (SPS) and electrochemical approach. As a methodology, the concept can be extended to new methods of electrodeposition, patterning, and grafting of conjugated polymers on electrochemically addressable metal surfaces. Compared to spin-cast or electropolymerized monomer films, they are very robust both thermally and mechanically. Other applications of these films to sensors, dielectric materials, non-lithographic patterning, etc. are currently being investigated.

The Precursor Polymer Approach to Electrodeposition and Patterning of Conjugated Polymer Ultrathin Films

2001 ◽  
Vol 708 ◽  
Author(s):  
Rigoberto Advincula ◽  
Chuanjun Xia ◽  
Prasad Taranekar ◽  
Suxiang Deng ◽  
Ken Onishi
Keyword(s):  
Ultrathin Films ◽  
Optical Quality ◽  
Polymer Backbone ◽  
High Optical Quality ◽  
Electrode Surfaces ◽  
Flat Electrode ◽  
Precursor Polymer ◽  
Synthesis Design ◽  
Key Points

ABSTRACTIn this paper, we report strategies for electrodepositing and patterning ultrathin films of conjugated polymers on flat electrode surfaces using the precursor polymer approach. This involves a rational synthesis design of the precursor polymer followed by careful electrodeposition and characterization of ultrathin films on conducting substrates. This has resulted in the preparation of smooth, high optical quality films, which should be important for applications involving flat electrode surfaces in devices. Characterization was made using surface sensitive spectroscopic and microscopic techniques. Copolymerization with monomers, polymer backbone design, and grafting on modified surfaces are key points in this strategy. Novel methods of in-situ characterization techniques have also been developed combing electrochemistry and surface plasmon resonance techniques.

Molecular-Level Control in The Deposition of Ultrathin Films of Highly Conductive, In-Situ Polymerized P-Doped Conjugated Polymers

1993 ◽  
Vol 328 ◽  
Author(s):  
A. C. Fou ◽  
D. L. Ellis ◽  
M. F. Rubner
Keyword(s):  
Conducting Polymers ◽  
Conjugated Polymers ◽  
Ultrathin Films ◽  
Self Assembly ◽  
Oxidative Polymerization ◽  
Multilayer Films ◽  
Solution Chemistry ◽  
Level Control ◽  
Multilayer Architecture

ABSTRACTA novel thin film processing technique has been developed for the fabrication of ultrathin films of conducting polymers with angstrom-level control over thickness and multilayer architecture. Molecular self-assembly of in-situ polymerized conjugated polymers consists of a layer-by-layer process in which a substrate is alternately dipped into a solution of a p-doped conducting polymer (e.g. polypyrrole, polyaniline) and a solution of a polyanion. In-situ oxidative polymerization produces the more highly conductive, underivatized form of the conjugated polymer, which is deposited in a single layer of precisely controlled thickness (30 to 60 Å). The thickness of each layer can be fine-tuned by adjusting the dipping time and the solution chemistry. The surface chemistry of the substrate (e.g. hydrophobic, charged, etc.) also strongly influences the deposition, thereby making it possible to selectively deposit conducting polypyrrole onto well defined regions of the substrates. Typical multilayer films exhibit conductivities in the range of 20–50 S/cm, but samples with conductivities as high as 300 S/cm have been realized. There is no limit to the number of layers that can be built up nor to the complexity of the multilayer architecture of the film; achieved simply by alternating the sequence of dips into solutions of various polycations and polyanions. This new self-assembly process opens up vast possibilities in applications which require large area, ultrathin films of conducting polymers and, more importantly, in applications that can take advantage of the unique interactions achievable in the complex, supermolecular architectures of multilayer films.

Epitaxial growth manner and structure of superconducting oxide films

1990 ◽  
Vol 48 (4) ◽  
pp. 2-3
Author(s):  
Yoshichika Bando ◽  
Takahito Terashima ◽  
Kenji Iijima ◽  
Kazunuki Yamamoto ◽  
Kazuto Hirata ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Film Surface ◽  
High Energy ◽  
Epitaxial Films ◽  
Layer By Layer ◽  
Initial Growth ◽  
In Situ Growth ◽  
High Quality ◽  
Activated Reactive Evaporation

The high quality thin films of high-Tc superconducting oxide are necessary for elucidating the superconducting mechanism and for device application. The recent trend in the preparation of high-Tc films has been toward “in-situ” growth of the superconducting phase at relatively low temperatures. The purpose of “in-situ” growth is to attain surface smoothness suitable for fabricating film devices but also to obtain high quality film. We present the investigation on the initial growth manner of YBCO by in-situ reflective high energy electron diffraction (RHEED) technique and on the structural and superconducting properties of the resulting ultrathin films below 100Å. The epitaxial films have been grown on (100) plane of MgO and SrTiO, heated below 650°C by activated reactive evaporation. The in-situ RHEED observation and the intensity measurement was carried out during deposition of YBCO on the substrate at 650°C. The deposition rate was 0.8Å/s. Fig. 1 shows the RHEED patterns at every stage of deposition of YBCO on MgO(100). All the patterns exhibit the sharp streaks, indicating that the film surface is atomically smooth and the growth manner is layer-by-layer.

A hybrid bulk-heterojunction photoanode for direct solar-to-chemical conversion

2021 ◽  
Author(s):  
Liang Yao ◽  
Yongpeng Liu ◽  
Han-Hee Cho ◽  
Meng Xia ◽  
Arvindh Sekar ◽  
...  
Keyword(s):  
Organic Semiconductor ◽  
Bulk Heterojunction ◽  
Polymer Network ◽  
Chemical Conversion ◽  
Solar Fuel ◽  
Fuel Production

The development of efficient and stable organic semiconductor-based photoanodes for solar fuel production is advanced by using a robust in situ-formed covalent polymer network together with a mesoporous inorganic film in a hybrid bulk heterojunction.

scholarly journals Biomimetic Transparent Eye Protection Inspired by the Carapace of an Ostracod (Crustacea)

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 663
Author(s):  
Andrew R. Parker ◽  
Barbara P. Palka ◽  
Julie Albon ◽  
Keith M. Meek ◽  
Simon Holden ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Thin Film Deposition ◽  
Dielectric Materials ◽  
Scratch Resistance ◽  
Film Deposition ◽  
Original Form ◽  
Biomimetic Material ◽  
Eye Protection ◽  
Protection Coating

In this study we mimic the unique, transparent protective carapace (shell) of myodocopid ostracods, through which their compound eyes see, to demonstrate that the carapace ultrastructure also provides functions of strength and protection for a relatively thin structure. The bulk ultrastructure of the transparent window in the carapace of the relatively large, pelagic cypridinid (Myodocopida) Macrocypridina castanea was mimicked using the thin film deposition of dielectric materials to create a transparent, 15 bi-layer material. This biomimetic material was subjected to the natural forces withstood by the ostracod carapace in situ, including scratching by captured prey and strikes by water-borne particles. The biomimetic material was then tested in terms of its extrinsic (hardness value) and intrinsic (elastic modulus) response to indentation along with its scratch resistance. The performance of the biomimetic material was compared with that of a commonly used, anti-scratch resistant lens and polycarbonate that is typically used in the field of transparent armoury. The biomimetic material showed the best scratch resistant performance, and significantly greater hardness and elastic modulus values. The ability of biomimetic material to revert back to its original form (post loading), along with its scratch resistant qualities, offers potential for biomimetic eye protection coating that could enhance material currently in use.

In Situ Magnetic-Circular-X-Ray-Dichroism Measurements: An Epitaxial Fe Wedge on Cu(100)

MRS Bulletin ◽  
1999 ◽  
Vol 24 (1) ◽  
pp. 41-45 ◽  
Author(s):  
M.E. Dávila ◽  
D. Arvanitis ◽  
J. Hunter Dunn ◽  
N. Mårtensson ◽  
P. Srivastava ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Magnetic Circular Dichroism ◽  
Polarized Light ◽  
Measured Quantity ◽  
Easy Magnetization ◽  
Magnetization Direction ◽  
Core Electron ◽  
Circularly Polarized ◽  
X Ray

Circularly polarized x-ray radiation is attracting increasing interest as a tool for the characterization of the electronic, magnetic, and chiral properties of low-dimensional structures. Using circular light (with electric field vector parallel to the orbital plane), a dependence of the measured quantity by changing either the orientation of the light polarization or the magnetization is indicative of the existence of magnetic circular dichroism. It can be observed in x-ray absorption spectroscopy (XAS), in which the photon energy is scanned through an absorption threshold exciting a core electron into an unoccupied valence state using circularly polarized light. Synchrotron radiation sources have made this technique possible. It can also be observed in photo-emission spectroscopy from core and valence levels. Here we focus on magnetic circular x-ray dichroism (MCXD) in XAS as an element-specific tool to investigate magnetic properties of ultrathin films in situ. The application of magneto-optical sum rules enables the determination of the orbital and spin magnetic moments per atom from XAS spectra, as well as the easy magnetization direction.MCXD-based magnetometry in XAS is extensively used by measuring the L absorption edges of 3d-transition metals, where large intensity changes (up to 60%) of the L-edge white lines are observed upon reversal of either the sample magnetization or the light helicity. The high magnetic contrast obtained, combined with the elemental specificity of the technique, allows for the study of very dilute samples such as ultrathin films. We first concentrate on the selection rules governing MCXD in XAS.

Cyclic Voltammetry, Impedance Measurements and In-Situ EPR Studies of Conjugated Polymers

1991 ◽  
Vol 21 ◽  
pp. 139-162 ◽  
Author(s):  
L. Wuckel ◽  
M. Schwarzenberg ◽  
A. Bartl ◽  
H.G. Döge
Keyword(s):  
Cyclic Voltammetry ◽  
Conjugated Polymers ◽  
Impedance Measurements
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