Pulse electrolysis

Last updated
Pulse Electrolysis
Experimental Electrolysis Cell.png
A Simplified Experimental Pulse Electrolysis Cell
Typical Materials
Type of Electrolysis:PDC Electrolysis
Catalyst material on the anodeAluminium
Catalyst material on the cathodeAluminium
State-of-the-art Operating Ranges
Cell temperature25 ± 2°C
Current density400 mA
Cell voltage+18 V DC
Cell voltage efficiency60-70%

Pulse electrolysis is an alternate electrolysis method that utilises a pulsed direct current to initiate non-spontaneous chemical reactions. [1] [2] [3] Also known as pulsed direct current (PDC) electrolysis, the increased number of variables that it introduces to the electrolysis method can change the application of the current to the electrodes and the resulting outcome. [4] [5] This varies from direct current (DC) electrolysis, which only allows the variation of one value, the voltage applied. By utilising conventional pulse width modulation (PMW), multiple dependent variables can be altered, including the type of waveform, typically a rectangular pulse wave, the duty cycle, and the frequency. Currently, there has been a focus on theoretical and experimental research into PDC electrolysis in terms of the electrolysis of water to produce hydrogen. Past research has demonstrated that there is a possibility it can result in a higher electrical efficiency in comparison to DC electrolysis. [5] This would allow electrolysis procedures to produce greater volumes of hydrogen with a reduced electrical energy consumption. [4] Although theoretical research has made large promise for the efficiencies and benefits of utilising pulse electrolysis, it has many contradictions including a common issue that it is difficult to replicate the successes of patents experimentally and produces its own negative effects on the electrolyser. [5]

Contents

PDC electrolysis is not only confined to the electrolysis of water. Uses in industry such as electroplating and electrocrystallisation are also undergoing research due to the wider range of properties that can be achieved. [6]

The various and alterable effects of using intermittent pulses in PDC electrolysis has resulted in an area of interest that could benefit industry. However, as it is still being researched and has produced conflicting results, a consistent and reliable answer to how dependent electrolysis efficiency is on the properties of an electrical pulse has not been determined, [4] hence, other forms of electrolysis such as polymer electrolyte membrane and alkaline water electrolysis are being used in industry.

Research history

PDC electrolysis was first considered theoretically in 1952, [7] and experimental research began as early as 1960 however it was originally focused on its technical applications to industry and the possibilities of improving the quality and rate of metal deposition. [8] It partially succeeded, providing promising results its ability to create smoother, denser deposits, and reducing the amount of metal required in electroplating. [6]

The first instance it was considered to initialise the electrolysis of water was from the perspective of magnetolysis in 1985, where high strength magnets, or in this case electromagnets, are used in conjunction with homopolar propellers. [9] Ghoroghichian and Bockris conducted this experimental research to determine how a pulsed current can impact the rate of hydrogen production and provide economic advantages. A current density ratio of 2.07 was observed, demonstrating, for the first time, that a pulsed current can double the production of hydrogen, in comparison to a steady state current. [10]

Since hydrogen gas cannot be collected in its free form, and it can be used to provide a source of renewable and clean energy through fuel cells, [11] [12] discovering an electrolysis method with the greatest efficiency is valued. With early experimental and theoretical success, many patents began to be developed until as recent as 2002,[ citation needed ] but since 1985, it has only been researched intermittently with varying levels of success. [13]

Experimental research

With the perspective that the current use of non-renewable fuel sources is a main cause of global environmental problems, [7] hydrogen is being viewed as a possible renewable fuel source replacement. [11] For this to be feasible, the production of hydrogen, through methods such as electrolysis, must be efficient in terms of the energy, cost and time required. [13] Whilst multiple methods of pulse electrolysis have been studied, and experimental results are mixed, the underlying theory behind this experimental approach seems to remain consistent. [13]

Double Layer Double Layer.png
Double Layer

Theoretical Concept

When a voltage is applied to an electrolysis cell, immediately following this an Electric Double Layer (EDL), or a diffusion layer, is theoretically formed. This can create a capacitance, or can cause the electrolyser to act as a capacitor. [13] When this is present, excess voltage must be supplied by the direct current to compensate for the loss in the 'capacitor', [14] which rises the required voltage supplied to what is called the thermo-neutral voltage. [4] One of the aims of PDC electrolysis is to overcome this, and theoretically, when the PMW switches the current on, a capacitance will be stored, and when the duty cycle is over, it will be released, continuing the flow of current whilst reducing the EDL that is formed. [4]

Poláčik and Pospíšil believe that by manipulating the dependent variables, such as the duty cycle, can increase or decrease the effectiveness of pulse electrolysis at reducing this layer. [4] A theoretical equation, the Sand equation, is used to calculate the amount of time required to allow the EDL to fall to zero, and allow PDC electrolysis to achieve its highest efficiencies. [15]

Use in Magnetolisis

Electrolysers require high currents produced by very low voltages. [10] [16] A homopolar generator has the ability to do this, so in Bockris and Ghoroghchian's original experiment in 1985, they followed Faraday's idea. Using a magnetic field of 0.86T produced by permanent magnets, they placed a stainless-steel disc in between. The disc needed a rotation speed of 2000 rpm to reach the correct electrical potential for electrolysis. The difference between Faraday's original model and Bockris and Ghorogchian's is that their disc will only rotate when it is in contact with an electrolyte. [10]

They encountered one large problem, a viscous force created by the electrolyte, that slowed down the motion of the disc. The two ways they could fix this is to rotate the disc and solution together or increase the magnetic field used. The latter being most practicable, the required magnetic field was calculated according to the power consumption rate or producing a cubic meter of hydrogen. It was discovered a magnetic field of 11T was needed for effective electrolysis, [10] more than 16 times greater than what was originally used. Since superconducting magnets would be required, and they can become too expensive to justify their use, ruling this out as a possible method.

Faraday disk generator the Magnetolysis design was based on Faraday disk generator.jpg
Faraday disk generator the Magnetolysis design was based on

Their final decision was to use a homopolar generator as an external source of power. This follows Faraday's method more closely.

In this method, a pulse potential was created to take advantage of previous studies that give an effectiveness factor of 2 when either a nickel electrode [10] or a Teflon-bonded platinum electrode was used. [15]

The generator was constructed with a magnetic flux density of 0.6T, a propeller radius of 30 cm and a loop coated with copper strips. [10] To increase the output potential, and reducing the rotation speed required, these were connected in series. Pulses of 2-3V that were sustained for 1ms were achieved. [10]

This was the first instance of a successful application of pulse electrolysis for the production of hydrogen. However, it still presents its own limitations in the possibility for it to be used in industry.

Conflicting research

A comparison between a pulsed and non-pulsed dc current electrolysers was explored in 1993 by Shaaban, that demonstrated a non-pulsed current used the least electrical power. This opposes the previous and future works conducted. [5]

The experimental electrolyser separated the anolyte and catholyte compartments and used a 324-Naflon membrane to allow the ion exchange. The distance between the anode, made with platinum coated titanium, and the cathode, stainless steel, was 3mm and was immersed in a 10 weight percent sulfuric acid electrolyte. He conducted tests under several different frequencies that included '0.01 Hz, 0.5 kHz, 5 kHz, i kHz, 10 kHz, 25 kHz, and 40 kHz' and with four duty cycles, '10, 25, 50, and 80%'. [5]

Initial observations revealed that the off-period resulted in a reversal in polarity, causing the reaction to reverse. This effected the cathode, which displayed a 2g loss after experimentation. [5] A diode was input into the circuit to rectify the polarity. However, the cell was prevented from dropping to 0 V during the off-period, maintaining a higher value of 2.3V. This further impacted the experiment, distorting the square wave produced by the function generator Shaaban used, as the electrical potential provided needed to overcome the cell voltage of 2.3V before current could flow. [5] Bokris et al. records that current would continue to flow, discharging ions from the EDL, but this was contradicted in this experiment. [7] This only occurred when the diode was in place but it prevented a current spike in the duty cycle as well.

With a 10% duty cycle at a 1 kHz pulse, temperature increases of nearly 7 °C greater than in the non-pulsed experimental electrolysis, were found. [5] Temperature increases can prevent the circuit

Calculating the power consumption, it was determined a non-pulsed current had power demand losses of 3.5%, and a pulsed current resulted in 13 - 16% losses. [5] It also opposes the idea from Bockris et al. that the effectiveness of non-pulsed dc current electrolysis increases by a factor of 2 when a pulsed current is applied. [10]

Industrial Uses

The possible increased effect a pulsed current will have on the corrodibility of metals was first looked at by de la Rive in 1837. [17] It was investigated around 60 years later by Coehn regarding the effect of a current with a rectangular waveform, on the plating of zinc deposits, resulting in a successful application for a patent. [18] [19] A full review on using PDC electrolysis in electroplating, also known as electrodeposition or 'pulse plating', was only published in 1954 by Baeyens, this being the first area of research into the use of pulse electrolysis in industry. [18] [20]

A pulsed current can be varied in many ways that increases the possible outcomes and can vary the properties of deposited metals during electroplating. [4] [5] [20] Hansel and Roy, in their review of the third European Pulse Plating Seminar, concluded that each deposition system must have a unique sequence developed in order to optimise the process and gain the desired results, opposing the inability of traditional plating to be as freely tailored to a situation. [21] The nucleation and crystallisation of the deposition metal is directly affected and can have favourable or unfavourable circumstances if specific conditions are not met. [21] It is reported that pulse plating can encourage nucleation causing grain refinement, and reducing grain size, as well as increasing the deposit density that can improve micro hardness. [21] [22]

These effects were first researched on zinc by Coehn. [19] It was discovered a pulsed current at a high frequency can produce deposits of higher quality, with properties ranging from a smoother finish by the reduction in grain size, [20] [23] as well as lowering its corrosion rate. [22] This is beneficial as it is mainly used as a sacrificial anode in industry. [23]

Advantages

In theoretical electrolysis of water, a voltage of only 1.23 V is required to split water into hydrogen and oxygen, The formation of an EDL increases this to its thermo-neutral voltage of 1.45 V. Minimising the EDL formed during pulse electrolysis is advantageous, as it can reduce the thermo-neutral voltage and the energy input required, increasing energy efficiency. [4]

Disadvantages

Whilst the method of PDC electrolysis has been proven by Ghoroghichian and Bockris in 1952 and 1985 to work extremely well in theory, it is difficult to replicate with consistently positive results in practical experimentation. Hence, the many mechanisms that have been patented are unable to be repeated and used in industry.[ citation needed ]

According to Shabaan, during the pulse-off period, if the electrolytic cell is not constructed properly, the current polarity can reverse. This can cause the cathode to deteriorate. [5] In electrolysis, the cathode is where the reduction of hydrogen occurs, forming the desired hydrogen gas. Any loss in mass can reduce the speed and effectiveness of the electrolytic reaction, reducing the overall efficiency of the pulse electrolysis method.

Shaaban also states that due to expected internal losses, such as through heat, the current density required will increase, which increases the required voltage. [24] As a result, greater over potentials are needed that further converts to heat. [5]

Related Research Articles

<span class="mw-page-title-main">Electrochemistry</span> Branch of chemistry

Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential difference and identifiable chemical change. These reactions involve electrons moving via an electronically-conducting phase between electrodes separated by an ionically conducting and electronically insulating electrolyte.

<span class="mw-page-title-main">Electrochemical cell</span> Electro-chemical device

An electrochemical cell is a device that generates electrical energy from chemical reactions. Electrical energy can also be applied to these cells to cause chemical reactions to occur. Electrochemical cells that generate an electric current are called voltaic or galvanic cells and those that generate chemical reactions, via electrolysis for example, are called electrolytic cells.

<span class="mw-page-title-main">Electrolysis</span> Technique in chemistry and manufacturing

In chemistry and manufacturing, electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell. The voltage that is needed for electrolysis to occur is called the decomposition potential. The word "lysis" means to separate or break, so in terms, electrolysis would mean "breakdown via electricity".

<span class="mw-page-title-main">Electroplating</span> Creation of protective or decorative metallic coating on other metal with electric current

Electroplating, also known as electrochemical deposition or electrodeposition, is a process for producing a metal coating on a solid substrate through the reduction of cations of that metal by means of a direct electric current. The part to be coated acts as the cathode of an electrolytic cell; the electrolyte is a solution of a salt of the metal to be coated; and the anode is usually either a block of that metal, or of some inert conductive material. The current is provided by an external power supply.

<span class="mw-page-title-main">Electrolytic cell</span> Cell that uses electrical energy to drive a non-spontaneous redox reaction

An electrolytic cell is an electrochemical cell that utilizes an external source of electrical energy to force a chemical reaction that would otherwise not occur. The external energy source is a voltage applied between the cell's two electrodes; an anode and a cathode, which are immersed in an electrolyte solution. This is in contrast to a galvanic cell, which itself is a source of electrical energy and the foundation of a battery. The net reaction taking place in a galvanic cell is a spontaneous reaction, i.e., the Gibbs free energy remains -ve, while the net reaction taking place in an electrolytic cell is the reverse of this spontaneous reaction, i.e., the Gibbs free energy is +ve.

A regenerative fuel cell or reverse fuel cell (RFC) is a fuel cell run in reverse mode, which consumes electricity and chemical B to produce chemical A. By definition, the process of any fuel cell could be reversed. However, a given device is usually optimized for operating in one mode and may not be built in such a way that it can be operated backwards. Standard fuel cells operated backwards generally do not make very efficient systems unless they are purpose-built to do so as with high-pressure electrolysers, regenerative fuel cells, solid-oxide electrolyser cells and unitized regenerative fuel cells.

<span class="mw-page-title-main">High-temperature electrolysis</span> Technique for producing hydrogen from water

High-temperature electrolysis is a technology for producing hydrogen from water at high temperatures.

<span class="mw-page-title-main">Electrolysis of water</span> Electricity-induced chemical reaction

Electrolysis of water is using electricity to split water into oxygen and hydrogen gas by electrolysis. Hydrogen gas released in this way can be used as hydrogen fuel, but must be kept apart from the oxygen as the mixture would be extremely explosive. Separately pressurised into convenient 'tanks' or 'gas bottles', hydrogen can be used for oxyhydrogen welding and other applications, as the hydrogen / oxygen flame can reach approximately 2,800°C.

<span class="mw-page-title-main">Electrogravimetry</span> Method of chemical analysis

Electrogravimetry is a method used to separate and quantify ions of a substance, usually a metal. In this process, the analyte solution is electrolyzed. Electrochemical reduction causes the analyte to be deposited on the cathode. The mass of the cathode is determined before and after the experiment, and the difference is used to calculate the mass of analyte in the original solution. Controlling the potential of the electrode is important to ensure that only the metal being analyzed will be deposited on the electrode.

In electrochemistry, overpotential is the potential difference (voltage) between a half-reaction's thermodynamically-determined reduction potential and the potential at which the redox event is experimentally observed. The term is directly related to a cell's voltage efficiency. In an electrolytic cell the existence of overpotential implies that the cell requires more energy than thermodynamically expected to drive a reaction. In a galvanic cell the existence of overpotential means less energy is recovered than thermodynamics predicts. In each case the extra/missing energy is lost as heat. The quantity of overpotential is specific to each cell design and varies across cells and operational conditions, even for the same reaction. Overpotential is experimentally determined by measuring the potential at which a given current density is achieved.

Hydrogen gas is produced by several industrial methods. Fossil fuels are the dominant source of hydrogen. As of 2020, the majority of hydrogen (~95%) is produced by steam reforming of natural gas and other light hydrocarbons, and partial oxidation of heavier hydrocarbons. Other methods of hydrogen production include biomass gasification and methane pyrolysis. Methane pyrolysis and water electrolysis can use any source of electricity including renewable energy.

Plasma activation is a method of surface modification employing plasma processing, which improves surface adhesion properties of many materials including metals, glass, ceramics, a broad range of polymers and textiles and even natural materials such as wood and seeds. Plasma functionalization also refers to the introduction of functional groups on the surface of exposed materials. It is widely used in industrial processes to prepare surfaces for bonding, gluing, coating and painting. Plasma processing achieves this effect through a combination of reduction of metal oxides, ultra-fine surface cleaning from organic contaminants, modification of the surface topography and deposition of functional chemical groups. Importantly, the plasma activation can be performed at atmospheric pressure using air or typical industrial gases including hydrogen, nitrogen and oxygen. Thus, the surface functionalization is achieved without expensive vacuum equipment or wet chemistry, which positively affects its costs, safety and environmental impact. Fast processing speeds further facilitate numerous industrial applications.

In electrochemistry, Faraday efficiency describes the efficiency with which charge (electrons) is transferred in a system facilitating an electrochemical reaction. The word "Faraday" in this term has two interrelated aspects: first, the historic unit for charge is the faraday (F), but has since been replaced by the coulomb (C); and secondly, the related Faraday's constant correlates charge with moles of matter and electrons. This phenomenon was originally understood through Michael Faraday's work and expressed in his laws of electrolysis.

<span class="mw-page-title-main">Solid oxide electrolyzer cell</span> Type of fuel cell

A solid oxide electrolyzer cell (SOEC) is a solid oxide fuel cell that runs in regenerative mode to achieve the electrolysis of water by using a solid oxide, or ceramic, electrolyte to produce hydrogen gas and oxygen. The production of pure hydrogen is compelling because it is a clean fuel that can be stored, making it a potential alternative to batteries, methane, and other energy sources. Electrolysis is currently the most promising method of hydrogen production from water due to high efficiency of conversion and relatively low required energy input when compared to thermochemical and photocatalytic methods.

Electrochemical engineering is the branch of chemical engineering dealing with the technological applications of electrochemical phenomena, such as electrosynthesis of chemicals, electrowinning and refining of metals, flow batteries and fuel cells, surface modification by electrodeposition, electrochemical separations and corrosion.

<span class="mw-page-title-main">Supercapacitor</span> High-capacity electrochemical capacitor

A supercapacitor (SC), also called an ultracapacitor, is a high-capacity capacitor, with a capacitance value much higher than solid-state capacitors but with lower voltage limits. It bridges the gap between electrolytic capacitors and rechargeable batteries. It typically stores 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerates many more charge and discharge cycles than rechargeable batteries.

<span class="mw-page-title-main">Proton exchange membrane electrolysis</span> Technology for splitting water molecules

Proton exchange membrane(PEM) electrolysis is the electrolysis of water in a cell equipped with a solid polymer electrolyte (SPE) that is responsible for the conduction of protons, separation of product gases, and electrical insulation of the electrodes. The PEM electrolyzer was introduced to overcome the issues of partial load, low current density, and low pressure operation currently plaguing the alkaline electrolyzer. It involves a proton-exchange membrane.

<span class="mw-page-title-main">Electrochemical stripping analysis</span> Method of chemical analysis

Electrochemical stripping analysis is a set of analytical chemistry methods based on voltammetry or potentiometry that are used for quantitative determination of ions in solution. Stripping voltammetry have been employed for analysis of organic molecules as well as metal ions. Carbon paste, glassy carbon paste, and glassy carbon electrodes when modified are termed as chemically modified electrodes and have been employed for the analysis of organic and inorganic compounds.

<span class="mw-page-title-main">Reversible solid oxide cell</span>

A reversible solid oxide cell (rSOC) is a solid-state electrochemical device that is operated alternatively as a solid oxide fuel cell (SOFC) and a solid oxide electrolysis cell (SOEC). Similarly to SOFCs, rSOCs are made of a dense electrolyte sandwiched between two porous electrodes. Their operating temperature ranges from 600°C to 900°C, hence they benefit from enhanced kinetics of the reactions and increased efficiency with respect to low-temperature electrochemical technologies.

<span class="mw-page-title-main">Anion exchange membrane electrolysis</span> Splitting of water using a semipermeable membrane

Anion exchange membrane(AEM) electrolysis is the electrolysis of water that utilises a semipermeable membrane that conducts hydroxide ions (OH−) called an anion exchange membrane. Like a proton-exchange membrane (PEM), the membrane separates the products, provides electrical insulation between electrodes, and conducts ions. Unlike PEM, AEM conducts hydroxide ions. The major advantage of AEM water electrolysis is that a high-cost noble metal catalyst is not required, low-cost transition metal catalyst can be used instead. AEM electrolysis is similar to alkaline water electrolysis, which uses a non-ion-selective separator instead of an anion-exchange membrane.

References

  1. ↑ "Pulse electrolysis of alkaline solutions as highly efficient method of production of hydrogen/oxygen gas mixtures". ResearchGate. Retrieved 2019-05-31.
  2. ↑ Morita, K.; Furuya, Etuo. (1994-07-01). "Pulse electrolysis within a solution boundary layer to minimize convective effects". Analytical Chemistry. U.S.: American Chemical Society. 66 (13): 2197–2199. doi:10.1021/ac00085a042.
  3. ↑ Kireev, S. Yu. (2017-03-01). "Intensification of processes of electrodeposition of metals by use of various modes of pulse electrolysis". Inorganic Materials: Applied Research. Springer Science+Business Media. 8 (2): 203–210. doi:10.1134/S2075113317020095. S2CID   99479894.
  4. 1 2 3 4 5 6 7 8 Poláčik, Ján; Pospíšil, Jiří (2016-10-01). "Some Aspects of PDC Electrolysis". Technological Engineering. 13 (1): 33–34. Bibcode:2016TeEng..13...33P. doi:10.2478/teen-2016-0011. ISSN   2451-3156. S2CID   99125043.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 Shaaban, Aly H. (1993). "Water Electrolysis and Pulsed Direct Current". Journal of the Electrochemical Society. 140 (10): 2863–2867. Bibcode:1993JElS..140.2863S. doi:10.1149/1.2220923.
  6. 1 2 Ibl, N.; Puippe, J.Cl.; Angerer, H. (1978). "Electrocrystallization in pulse electrolysis". Surface Technology. 6 (4): 287–300. doi:10.1016/0376-4583(78)90044-4.
  7. 1 2 3 Bockris, J. O'M.; Potter, E. C. (1952). "The Mechanism of Hydrogen Evolution at Nickel Cathodes in Aqueous Solutions". The Journal of Chemical Physics. 20 (4): 614–628. Bibcode:1952JChPh..20..614B. doi:10.1063/1.1700503. ISSN   0021-9606.
  8. ↑ Arouete, S.; Blurton, K. F.; Oswin, H. G. (1969). "Controlled Current Deposition of Zinc from Alkaline Solution". Journal of the Electrochemical Society. 116 (2): 166. Bibcode:1969JElS..116..166A. doi:10.1149/1.2411787.
  9. ↑ Ehrenhaft, Felix (1944-05-01). "The Decomposition of Water by the So-Called Permanent Magnet and the Measurement of the Intensity of the Magnetic Current". Physical Review. 65 (9–10): 287–289. Bibcode:1944PhRv...65..287E. doi:10.1103/PhysRev.65.287.2. ISSN   0031-899X.
  10. 1 2 3 4 5 6 7 8 Ghoroghchian, J; Bockris, J (1985). "Use of a homopolar generator in hydrogen production from water". International Journal of Hydrogen Energy. 10 (2): 101–112. Bibcode:1985IJHE...10..101G. doi:10.1016/0360-3199(85)90042-4.
  11. 1 2 Nicoletti, Giovanni; Arcuri, Natale; Nicoletti, Gerardo; Bruno, Roberto (2015). "A technical and environmental comparison between hydrogen and some fossil fuels". Energy Conversion and Management. 89: 205–213. doi:10.1016/j.enconman.2014.09.057.
  12. ↑ Shinnar, Reuel (2003). "The hydrogen economy, fuel cells, and electric cars". Technology in Society. 25 (4): 455–476. doi:10.1016/j.techsoc.2003.09.024.
  13. 1 2 3 4 Monk, Nigel; Watson, Simon (2016). "Review of pulsed power for efficient hydrogen production". International Journal of Hydrogen Energy. 41 (19): 7782–7791. doi:10.1016/j.ijhydene.2015.12.086.
  14. ↑ Clément, N.; Nishiguchi, K.; Dufreche, J. F.; Guerin, D.; Fujiwara, A.; Vuillaume, D. (2013-08-14). "Water Electrolysis and Energy Harvesting with Zero-Dimensional Ion-Sensitive Field-Effect Transistors". Nano Letters. 13 (8): 3903–3908. arXiv: 1307.6723 . Bibcode:2013NanoL..13.3903C. doi:10.1021/nl4019879. ISSN   1530-6984. PMID   23879333. S2CID   20925098.
  15. 1 2 Tseung, A.C.C.; Vassie, P.R. (1976). "A study of gas evolution in teflon bonded porous electrodes—III. Performance of teflon bonded Pt black electrodes for H2 evolution". Electrochimica Acta. 21 (4): 315–318. doi:10.1016/0013-4686(76)80026-6.
  16. ↑ Carmo, Marcelo; Fritz, David L.; Mergel, Jürgen; Stolten, Detlef (2013). "A comprehensive review on PEM water electrolysis". International Journal of Hydrogen Energy. 38 (12): 4901–4934. doi:10.1016/j.ijhydene.2013.01.151.
  17. ↑ de la Rive, A (1837). Comptes Rendus. 4: 835–840.
  18. 1 2 Pesco, Anthony M.; Cheh, Huk Y. (1989), "Theory and Applications of Periodic Electrolysis", Modern Aspects of Electrochemistry, Springer US, pp. 251–293, doi:10.1007/978-1-4684-8667-4_4, ISBN   9781468486698
  19. 1 2 A. Coehn, German Patent, 75482 (1893)
  20. 1 2 3 Baeyens, P. (1954). "Electroplating with Modulated Current". Transactions of the IMF. 31 (1): 429–453. doi:10.1080/00202967.1954.11869655. ISSN   0020-2967.
  21. 1 2 3 Hansal, Wolfgang; Roy, Sudipta (2008). "Pulse plating gaining importance – Review of the 3rdEuropean Pulse Plating Seminar". Transactions of the IMF. 86 (5): 249–250. doi:10.1179/174591908x345897. ISSN   0020-2967. S2CID   109143443.
  22. 1 2 Ramanauskas, R.; Gudavičiūtė, L.; Ščit, O.; Bučinskienė, D.; Juškėnas, R. (2008). "Pulse plating effect on composition and corrosion properties of zinc alloy coatings". Transactions of the IMF. 86 (2): 103–108. doi:10.1179/174591908X272924. ISSN   0020-2967. S2CID   96146510.
  23. 1 2 Giurlani, Walter; Zangari, Giovanni; Gambinossi, Filippo; Passaponti, Maurizio; Salvietti, Emanuele; Di Benedetto, Francesco; Caporali, Stefano; Innocenti, Massimo (2018-07-25). "Electroplating for Decorative Applications: Recent Trends in Research and Development". Coatings. 8 (8): 260. doi: 10.3390/coatings8080260 . hdl: 11392/2436643 . ISSN   2079-6412.
  24. ↑ Fang, YaHui; Liu, Zhi-Pan (2010). "Electrochemical reactions at the electrode/solution interface: Theory and applications to water electrolysis and oxygen reduction". Science China Chemistry. 53 (3): 543–552. doi:10.1007/s11426-010-0047-6. ISSN   1674-7291. S2CID   96201556.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.