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39-496: The discovery of metal phthalocyanines can be traced to the observation of intensely colored byproducts from reactions of phthalic acid (benzene-1,2-dicarboxylic acid) or its derivatives with sources of nitrogen and metals. CuPc (copper phthalocyanine) was first prepared in 1927 by the reaction of copper(I) cyanide and o -dibromobenzene , which mainly produces colorless phthalonitrile as well as an intensely blue by-product. A couple of years later, workers at Scottish Dyes observed

78-473: A wire , transistor , or rectifier . This concept of using a molecule as a traditional electronic component was first presented by Aviram and Ratner in 1974, when they proposed a theoretical molecular rectifier composed of donor and acceptor sites which are insulated from one another. Single-molecule electronics is an emerging field, and entire electronic circuits consisting exclusively of molecular sized compounds are still very far from being realized. However,

117-661: A component of organic field-effect transistors . Copper Phthalocyanine (CuPc) has been suggested for data storage in quantum computing , due to the length of time its electrons can remain in superposition. CuPc can be easily processed into a thin film for use in device fabrication, which makes it an attractive qubit candidate. Approximately 25% of all artificial organic pigments are phthalocyanine derivatives. Copper phthalocyanine dyes are produced by introducing solubilizing groups, such as one or more sulfonic acid functions. These dyes find extensive use in various areas of textile dyeing (Direct dyes for cotton ), for spin dyeing and in

156-416: A larger overlap and thus, a smaller Cu-Cu spacing (~3.8 Å) compared to the β phase (~4.8 Å). The compound is non-biodegradable, but not toxic to fish or plants. No specific dangers have been associated with this compound. Oral LD 50 in mammals is estimated to be greater than 5 g per kg, with no ill effects found at that level of ingestion, for chronic ingestion estimated dose of low concern

195-405: A p z orbital, which is orthogonal to the other three sigma-bonds. The electrons in these delocalized orbitals have high mobility when the material is doped by oxidation, which removes some of these delocalized electrons. Thus the conjugated p-orbitals form a one-dimensional electronic band , and the electrons within this band become mobile when it is emptied partly. Despite intensive research,

234-531: A reverse tendency for the baking process mainly on the grounds of economical and ecological concerns (solvent-free, shorter lead time). This approach involves heating phthalonitrile with a copper salt, usually copper(I)chloride at 200°C to 240°C. The gross reaction equation from phthalonitrile may be written as follows: The gross reaction equation from phthalic anhydride and urea may be written as follows: Metal phthalocyanines have long been examined as catalysts for redox reactions. Areas of interest are

273-473: A subsequent hydrolysis of the anhydride. Phthalic acid was first obtained by French chemist Auguste Laurent in 1836 by oxidizing naphthalene tetrachloride. Believing the resulting substance to be a naphthalene derivative, he named it "naphthalic acid". After the Swiss chemist Jean Charles Galissard de Marignac determined its correct formula, Laurent gave it its present name. Manufacturing methods in

312-703: A theoretical calculation of transport through a modified charge-transfer molecule with donor acceptor groups that would allow transport only in one direction, essentially like a semiconductor diode. This was a breakthrough that inspired many years of research in the field of molecular electronics. The biggest advantage of conductive polymers is their processability, mainly by dispersion . Conductive polymers are not plastics , i.e., they are not thermoformable, yet they are organic polymers, like (insulating) polymers. They can offer high electrical conductivity but have different mechanical properties than other commercially used polymers. The electrical properties can be fine-tuned using

351-408: Is Phthalogen Dye IBN. 1,3-Diiminoisoindolene, the intermediate formed during phthalocyanine manufacture, used in combination with a copper salt affords the dye GK 161. Copper phthalocyanine is also used as a source material for manufacture of Phthalocyanine Green G . Other related and commercially available phthalocyanines blue pigments are: Copper phthalocyanine is a complex of copper (II) with

390-432: Is also used. Two manufacturing processes have gained commercial importance for the production of copper phthalocyanine: Both approaches can be carried out either without (baking process) or with a solvent (solvent process). Higher yields may be achieved with the solvent process (> 95%) than with the baking process (70 to 80%), so that the solvent process has initially simulated more interest. However, recents trends show

429-400: Is of modest commercial importance, the closely related derivative phthalic anhydride is a commodity chemical produced on a large scale. Phthalic acid is one of three isomers of benzenedicarboxylic acid , the others being isophthalic acid and terephthalic acid . Phthalic acid is produced by the catalytic oxidation of naphthalene or ortho- xylene directly to phthalic anhydride and

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468-489: Is potentially suited for organic solar cells because of its high chemical stability and uniform growth. CuPc usually plays the role of the electron donor in donor/ acceptor based solar cells. One of the most common donor/acceptor architectures is CuPc/C 60 ( buckminsterfullerene ) which rapidly became a model system for the study of small organic molecules. Photon to electron conversion efficiency in such system reaches approximately 5%. CuPc has also been investigated as

507-411: Is to use the tip of a scanning tunneling microscope (STM) to contact molecules adhered at the other end to a metal substrate. Another popular way to anchor molecules to the electrodes is to make use of sulfur 's high chemical affinity to gold ; though useful, the anchoring is non-specific and thus anchors the molecules randomly to all gold surfaces, and the contact resistance is highly dependent on

546-532: Is very energy consuming. The first time in history molecular electronics are mentioned was in 1956 by the German physicist Arthur Von Hippel, who suggested a bottom-up procedure of developing electronics from atoms and molecules rather than using prefabricated materials, an idea he named molecular engineering. However the first breakthrough in the field is considered by many the article by Aviram and Ratner in 1974. In this article named Molecular Rectifiers, they presented

585-408: The oxygen reduction reaction and the sweetening of gas streams by removal of hydrogen sulfide . Due to its stability, phthalo blue is also used in inks , coatings, and many plastics . The pigment is insoluble and has no tendency to migrate in the material. It is a standard pigment used in printing ink and the packaging industry. Industrial production was of the order of 10,000 tonnes per annum in

624-460: The paper industry . Direct blue 86 is the sodium salt of CuPc- sulfonic acid , whereas direct blue 199 is the quaternary ammonium salt of the CuPc-sulfonic acid. The quaternary ammonium salts of these sulfonic acids are used as solvent dyes because of their solubility in organic solvents , such as Solvent Blue 38 and Solvent Blue 48. The dye derived from cobalt phthalocyanine and an amine

663-455: The 1980s and 1990s in Japan alone. The pigment is the highest volume pigment produced. All major artists' pigment manufacturers produce variants of copper phthalocyanine, designated color index PB15 (blue) and color indexes PG7 and PG36 (green) . A common component on the artist's palette, phthalo blue is a cool blue with a bias towards green. It has intense tinting strength and easily overpowers

702-409: The availability of stable and reproducible dispersions, poly(3,4-ethylenedioxythiophene) (PEDOT) and polyaniline have gained some large-scale applications. While PEDOT is mainly used in antistatic applications and as a transparent conductive layer in the form of PEDOT and polystyrene sulfonic acid (PSS, mixed form: PEDOT:PSS) dispersions, polyaniline is widely used to make printed circuit boards, in

741-455: The conjugate base of phthalocyanine , i.e. CuPc. The description is analogous to that for copper porphyrins, which are also formally derived by double deprotonation of porphyrins. CuPc belongs to the D 4h point group . It is paramagnetic with one unpaired electron per molecule. The substance is practically insoluble in water (< 0.1 g/100 ml at 20 °C (68 °F)), but soluble in concentrated sulfuric acid. Density of

780-495: The continuous demand for more computing power, together with the inherent limits of the present day lithographic methods make the transition seem unavoidable. Currently, the focus is on discovering molecules with interesting properties and on finding ways to obtain reliable and reproducible contacts between the molecular components and the bulk material of the electrodes. Molecular electronics operates at distances less than 100 nanometers. Miniaturization down to single molecules brings

819-416: The electronic properties of the setup and is highly sensitive to distances to conducting surfaces nearby. One of the biggest problems with measuring on single molecules is to establish reproducible electrical contact with only one molecule and doing so without shortcutting the electrodes. Because the current photolithographic technology is unable to produce electrode gaps small enough to contact both ends of

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858-443: The fabrication of electronic components. It is an interdisciplinary area that spans physics , chemistry , and materials science . The unifying feature is use of molecular building blocks to fabricate electronic components. Due to the prospect of size reduction in electronics offered by molecular-level control of properties, molecular electronics has generated much excitement. It provides a potential means to extend Moore's Law beyond

897-456: The final finish, to protect copper from corrosion and preventing its solderability. Newer nanostructured forms of conducting polymers provide fresh impetus to this field, with their higher surface area and better dispersability. Recently supramolecular chemistry has been introduced to the field, which provide new opportunity for developing next generation of molecular electronics. For example, two orders of magnitude current intensity enhancement

936-613: The foreseen limits of small-scale conventional silicon integrated circuits . Molecular scale electronics , also called single-molecule electronics, is a branch of nanotechnology that uses single molecules, or nanoscale collections of single molecules, as electronic components . Because single molecules constitute the smallest stable structures possible, this miniaturization is the ultimate goal for shrinking electrical circuits . Conventional electronic devices are traditionally made from bulk materials. Bulk methods have inherent limits, and are growing increasingly demanding and costly. Thus,

975-481: The form of phthalic anhydride is an important industrial chemical, used for making phthalates ( esters of phthalic acid) that are used as plasticizers . However, phthalic anhydride is usually not made by dehydration of phthalic acid but from p-xylene or naphthalene . It is a dibasic acid, with p K a s of 2.89 and 5.51. The monopotassium salt, potassium hydrogen phthalate is a standard acid in analytical chemistry . Typically phthalate esters are prepared from

1014-504: The formation of traces of phthalocyanine dyes in the synthesis of phthalimide by the reaction of phthalic anhydride and ammonia in the presence of metallic iron. In 1937, DuPont started producing copper phthalocyanine blue in the USA under the trade name Monastral Blue after it had been previously launched in Great Britain ( ICI ) and Germany ( I.G. Farbenindustrie ) in 1935. Difficulty

1053-487: The idea was born that the components could instead be built up atom by atom in a chemistry lab (bottom up) as opposed to carving them out of bulk material (top down). In single-molecule electronics, the bulk material is replaced by single molecules. That is, instead of creating structures by removing or applying material after a pattern scaffold, the atoms are put together in a chemistry lab. The molecules used have properties that resemble traditional electronic components such as

1092-418: The methods of organic synthesis and of advanced dispersion. The linear-backbone polymers such as polyacetylene , polypyrrole , and polyaniline are the main classes of conductive polymers. Poly(3-alkylthiophenes) are the archetypical materials for solar cells and transistors. Conducting polymers have backbones of contiguous sp hybridized carbon centers. One valence electron on each center resides in

1131-422: The mix when combined with other colors. It is a transparent staining color and can be applied using glazing techniques. It is present in a wide variety of products, such as color deposition hair conditioner, gel ink pens, eye patches, parfum, shampoo, skin-care products, soap, sunscreen, tattoo ink, toothpaste, and even turf colorants. CuPc has often been investigated in the context of molecular electronics . It

1170-442: The molecules tested (in the order of nanometers), alternative strategies are used. These include molecular-sized gaps called break junctions, in which a thin electrode is stretched until it breaks. One of the ways to overcome the gap size issue is by trapping molecular functionalized nanoparticles (internanoparticle spacing is matchable to the size of molecules), and later target the molecule by place exchange reaction. Another method

1209-404: The nineteenth century included oxidation of naphthalene tetrachloride with nitric acid, or, better, oxidation of the hydrocarbon with fuming sulfuric acid, using mercury or mercury(II) sulfate as a catalyst. Naphthalene, on oxidation with potassium permanganate or potassium dichromate , gives Phthalic anhydride, which, through hydrolysis with hot water, gives Phthalic acid. Phthalic acid in

Copper phthalocyanine - Misplaced Pages Continue

1248-698: The precise atomic geometry around the site of anchoring and thereby inherently compromises the reproducibility of the connection. To circumvent the latter issue, experiments have shown that fullerenes could be a good candidate for use instead of sulfur because of the large conjugated π-system that can electrically contact many more atoms at once than a single atom of sulfur. The shift from metal electrodes to semiconductor electrodes allows for more tailored properties and thus for more interesting applications. There are some concepts for contacting organic molecules using semiconductor-only electrodes, for example by using indium arsenide nanowires with an embedded segment of

1287-636: The relationship between morphology, chain structure, and conductivity is poorly understood yet. Due to their poor processability, conductive polymers have few large-scale applications. They have some promise in antistatic materials and have been built into commercial displays and batteries, but have had limits due to the production costs, material inconsistencies, toxicity, poor solubility in solvents, and inability to directly melt process. Nevertheless, conducting polymers are rapidly gaining attraction in new uses with increasingly processable materials with better electrical and physical properties and lower costs. With

1326-420: The scale down to a regime where quantum mechanics effects are important. In contrast to the case in conventional electronic components, where electrons can be filled in or drawn out more or less like a continuous flow of electric charge , the transfer of a single electron alters the system significantly. The significant amount of energy due to charging has to be taken into account when making calculations about

1365-459: The solid is ~1.6 g/cm. The color is due to a π–π* electronic transition, with λ max ≈ 610 nm. CuPc crystallizes in various forms (polymorphs). Five different polymorphs have been identified: phases α, β, η, γ and χ. The two most common structures in CuPc are the β phase and the metastable α phase. Those phases can be distinguished by the overlap of their neighboring molecules. The α phase has

1404-428: The widely available phthalic anhydride . Reduction of phthalic acid with sodium amalgam in the presence of water gives the 1,3-cyclohexadiene derivative. The toxicity of phthalic acid is moderate with LD 50 (mouse) of 550 mg/kg. The bacteria Pseudomonas sp. P1 degrades phthalic acid. Molecular electronics Molecular electronics is the study and application of molecular building blocks for

1443-443: The wider bandgap material indium phosphide used as an electronic barrier to be bridged by molecules. One of the biggest hindrances for single-molecule electronics to be commercially exploited is the lack of means to connect a molecular sized circuit to bulk electrodes in a way that gives reproducible results. Also problematic is that some measurements on single molecules are done at cryogenic temperatures , near absolute zero, which

1482-454: Was 0.2 mg/kg per day in rats. No evidence indicates carcinogenic effects. Sulfonated phthalocyanine has been found to cause neuroanatomical defects in developing chicken embryos when injected directly into incubating eggs. Phthalic acid In organic chemistry , phthalic acid is an aromatic dicarboxylic acid , with formula C 6 H 4 (CO 2 H) 2 and structure HO(O)C− C 6 H 4 − C(O)OH . Although phthalic acid

1521-760: Was experienced in forming stable dispersions with the first alpha forms, especially in mixtures with rutile titanium , where the blue pigment tended to flocculate . The beta form was more stable, as was the improved stabilized alpha form. Today, there are even more isomeric forms available. The substance, IUPAC name (29 H ,31 H -phthalocyaninato(2−)- N 29, N 30, N 31, N 32)copper(II), is known by many names such as monastral blue , phthalo blue , helio blue , thalo blue , Winsor blue , phthalocyanine blue , C.I. Pigment Blue 15:2 , copper phthalocyanine blue , copper tetrabenzoporphyrazine , Cu-phthaloblue , P.B.15.2 , C.I. 74160 , and British Rail Blue. Numerous other trade names and synonyms exist. The abbreviation "CuPc"

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