Cathodic electrophoretic deposition

The activities of CNTs have been evaluated by Girishkumar et al. [7] using ex situ EIS. Their study was conducted in a three-compartment electrochemical cell using a GDE electrode (a carbon fibre paper coated with SWCNTs and Pt black as an anode or cathode). Electrophoretic deposition was used to deposit both the commercially available carbon black (CB) for comparison and the SWCNT onto the carbon Toray paper. Commercially available Pt black from Johnson Matthey was used as the catalyst. In both cases, the loading of the electrocatalyst (Pt), the carbon support, and the geometric area of the electrode were kept the same. EIS was conducted in a potentiostatic mode at either an open circuit potential or controlled potentials. 

For the purposes of electrophoretic deposition, 1-methylpiperazine, a secondary-tertiary diamine, was chosen to attach a tertiary amine group to the polymer chain (see Figure 3). The stoichiometric ratio of amine to imide groups was adjusted in the range 0.25 to 0.65, and a ratio of 0.4 was found to be about optimum. The tertiary amine group was then available to be protonated with acid, forming the positively charged substituent requisite for emulsification and cathodic electrophoretic deposition. Both acetic acid and lactic acid were used successfully at a level stoichiometrically equivalent to that of the amine modifier. 

TiOj core and PT shell) particles have been reported recently [109], Cathodic electrophoretic deposition was used to fabricate solar cells with these hybrid particles. 

Zhitomirsky I (2002) Cathodic electrophoretic deposition of ceramic and organoceramic materials— fundamental... 

The electrolyte (YSZ) layer ( 40 fim thick) is applied to the cathode by EYD (see Section 3.6.9). Because this is an expensive route efforts are made to use more cost-effective methods, for example plasma-spraying and electrophoretic deposition followed by sintering. 

Electrophoretic deposition (EPD) is a colloidal process in which the charged colloidal particles are driven by a dc electric field to deposit on a substrate, forming a condensed film. This process is a combination of electrophoresis and deposition (Sarkar and Nicholson 1996). It has a long history and the first application was in 1927 for Th02 and tungsten deposition on a platinum cathode. Recently, photocatalyst semiconductor nanoparticles/microparticles have also been assembled by this... 

The use of electrophoretic methods allows one to coat the surface of electrodes (of cathodes as well as of anodes) with films of various composition. Electrophoretic deposition is more economical than electrolysis, and allows one to apply coatings of complex composition, as well as to carry out deposition in non-aqueous media. The latter is especially beneficial in cases when it is not desirable to carry out electrolysis in water due to the saturation of material with hydrogen gas (the so-called hydrogenation ,... 

Two different electrodeposition techniques are currently in use electrolytic and electrophoretic. Electrolytic deposition occurs at the surface of the cathode when water is reduced to produce hydrogen gas and hydroxyl ions, which results in an increased pH at the electrode surface [115, 118]. Electrophoretic deposition occurs when charged particles, dispersed or suspended in liquid medium, are attracted to and deposited onto a conductive substrate of opposite charge in the presence of an electric field [112, 113, 119]. 

The main deposition methods of NS-Ti02 onto stainless steels are cathodic arc deposition [532], electrophoretic deposition [533], anodic spark deposition (ASD) [534], the sol-gel method [535, 536], atmospheric pressure metal organic CVD (AP-MOCVD) [537, 538] and radio frequency (RF) magnetron sputtering [539]. Preparation methods and applications of NS-Ti02 thin films on stainless steel have been summarized in Table 15. 

Electrophoretic deposition is used for depositing thin films firom colloidal dispersion (11). Nanosized particles in a sol can be stabilized by steric or electrostatic means, and they develop a charge on the surface. When an electric field is applied, these charged particles move in response to the field and this motion is called electrophoresis for example, positively charged particles will deposit at the cathode. Nanorod arrays have been synthesized by a combination of sol preparation and electrophoretic deposition. The conditions employed for the growth of nanorod arrays by electrophoretic deposition are summarized in Table 7.1 (11). First, the sol is brought in contact with the template. Then a potential is applied (typically... 

Cathodic electrophoretic paint is the preferred polymeric material used to insulate the carbon fibers as the negative potentials required for deposition avoid any possibility of further oxidative dissolution of the carbon fiber. The usual approach for electrophoretic deposition is to suspend the article being coated in an appropriate suspension of polymer particles and polarising the iton versus a secondary electrode. 

The sols for electrophoretic deposition are prepared in the following procedure. The heat-treated titania particles are re-dispersed in EtOH, and then added to a 1 mass% ammonia water containing PAA (m.w. = 450,000). The concentrations of titania and PAA are 1 and 0.1 mass% in the whole sol, respectively. The molar ratio of EtOH/H20 is 8/2. By applying DC voltage on the electrodes immersed in the sol, the particles are electrophoresed to the anode to form a film. The anode as a coating substrate is stainless steel sheet (SUS430,40 x 25 x 1.0 mm ) and the cathode as a counter electrode is spiral stainless steel wire (SUS304, 0.9 mm in diameter). 

Electrophoretic Deposition n A direct-current process analogous to electroplating, used to coat electrically-conductive articles with plastics, deposited from aqueous lattices or dispersions. The cathode may be a noncorrodible metal such as stainless steel, generally serving as the container in which the process is performed. The DC potential is usually under 100 V. The deposited coatings are baked to remove residual water. Among available polymer lattices suitable for the process are PVC, polyvinylidene chloride, acrylics, nylons, polyesters, polytetrafluoroethylene, and polyethylene. 

Hence, the electrophoretic deposition from powder suspensions in organic media is a powerful tool for the production of apatite type lanthanum silicate (ATLS) based half cells with La2Nio sCuo 2O4+5 (LNC) or Lao sSro 2Nio 6Feo 403 (LSNF) cathodes. 

Electrochemical Characterization of Lao. ro.2Nio.4Feae03 cathode layer on apatite type lanthanum silicate electrolyte. The porous Lao sSro 2Nio 4Feo 6O3.5 cathode, with a thickness of approximately 30 un and a geometric area of 2.1 cm, was deposited on the electrolyte disk via electrophoretic deposition and then sintered at 1350 C for 5 hours. 

Electrocoating The deposition of larger-than-ion electrically charged particles (paint, glass, etc.) from an electrolyte under an applied voltage. The deposition is usually on the cathode (cathodic electrocoating) but can be on the anode (anodic electrocoating) side of the electrolytic cell. Also called Electrophoretic deposition. 

For more detailed theoretical considerations on electrophoretic deposition see The main fields of application of this electrodeposition are the preparation of insulated heater coils and of activated cathodes (a metal covered with a thin layer of oxides of the alkaline earths) for radio tubes and the preparation of rubber objects from latex In the last-named case a metal form is used as an anode in a latex to which filling substances and vulcanizers have been added in finely divided form In the deposit the different components are intimately mixed to a degree scarcely possible by mechanical methodes. After vulcanfeing, the quality of rubber objects prepared in this way is very good ... 

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