An electroosmotic pump is used for generating flow or pressure by use of an electric field. One application of this is removing liquid flooding

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

from channels and gas

diffusion Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical p ...

layers and direct hydration of the proton exchange membrane in the

membrane electrode assembly A membrane electrode assembly (MEA) is an assembled stack of proton-exchange membranes (PEM) or alkali anion exchange membrane (AAEM), catalyst and flat plate electrode used in fuel cells and polymer electrolyte membrane electrolysis, electrolyzers ...

(MEA) of the

proton exchange membrane fuel cell Proton-exchange membrane fuel cells (PEMFC), also known as polymer electrolyte membrane (PEM) fuel cells, are a type of fuel cell being developed mainly for transport applications, as well as for stationary fuel-cell applications and portable ...

s. Additionally, electroosmotic pumps have gained significant attention due to their potential applications in microfluidic channels, lab-on-a-chip devices, and biomedical engineering.

Principle

Electroosmotic pumps are fabricated from

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant f ...

nanospheres or hydrophilic porous glass, the

pump A pump is a device that moves fluids (liquids or gases), or sometimes Slurry, slurries, by mechanical action, typically converted from electrical energy into hydraulic or pneumatic energy. Mechanical pumps serve in a wide range of application ...

ing mechanism is generated by an external

electric field An electric field (sometimes called E-field) is a field (physics), physical field that surrounds electrically charged particles such as electrons. In classical electromagnetism, the electric field of a single charge (or group of charges) descri ...

applied on an electric double layer (EDL), generates high pressures (e.g., more than 340 atm (34

MPa MPA or mPa may refer to: Academia Academic degrees * Master of Performing Arts * Master of Professional Accountancy * Master of Public Administration * Master of Public Affairs Schools * Mesa Preparatory Academy * Morgan Park Academy * M ...

) at 12 kV applied potentials) and high flow rates (e.g., 40 ml/min at 100 V in a pumping structure less than 1 cm³ in volume). EO pumps are compact, have no moving parts, and scale favorably with fuel cell design. The EO pump might drop the parasitic load of water management in fuel cells from 20% to 0.5% of the fuel cell power.

Types

Cascaded electroosmotic pumps

High pressures or high flow rates are obtained by positioning several regular electroosmotic pumps in series or parallel respectively.

Porous electroosmotic pump

Pumps based on porous media can be created using sintered glass or microporous polymer membranes with appropriate

surface chemistry Surface science is the study of physics, physical and chemistry, chemical phenomena that occur at the interface (chemistry), interface of two phase (matter), phases, including solid–liquid interfaces, solid–gas interfaces, solid–vacuum int ...

Planar shallow electroosmotic pump

Planar shallow electroosmotic pumps are made of parallel shallow microchannels.

Electroosmotic micropumps

Electroosmotic effects can also be induced without external fields in order to power micron-scale motion. Bimetallic gold/silver patches have been shown to generate local fluid pumping by this mechanism when hydrogen peroxide is added to the solution. A related motion can be induced by silver phosphate particles, which can be tailored to generate reversible firework behavior among other properties. Titanium dioxide micromotors (TiO2) demonstrated swarming behavior in the absence or presence of additional fuels due to the self-generated electrolyte diffusioosmosis.

References

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External links

Electroosmotic pump and its applicationsPrinciples of electroosmotic pumps
Hydrogen technologies Pumps Microfluidics Fuel cells