It poses great problems to our society, making it the subject of investigation for many research groups, which dedicate great efforts to find means to prevent or control this process. The Universidad Autónoma de Madrid has tested a new protection technique that consists of the electrodeposition of a conductive polymer (polypyrrole) over the surface of a material like copper that is easily oxidised.
Copper is widely used for many applications and being a metal that oxidises relatively easily, its conservation represents a great economical benefit. Conventional methods to avoid or minimise corrosion of the material are in many cases short lived, very expensive and involve the use of toxic chemicals.
A recent article by Pilar Herrasti published in the Electrochimica Acta journal describes how copper has been successfully covered with a conductive polymer that creates a barrier with the corrosive environment while leaving the conductive property of the material untouched. Conductive polymers are remarkable materials - plastics with a slightly altered composition that make them capable of conducting electricity. Synthesising these polymers is not complicated and the process can be varied to increase or decrease their conductivity.
When an oxidising potential is applied to a pyrrole solution, it oxidises the compound over the electrode, and a thin film of the material is laid over the metal. In the case of copper, the methodology involves generating a layer of copper oxide over which the polymer is deposited. This layer is conductive like the metal and since it is deposited in an oxidised state it can then be reduced, maintaining the copper in the passivity zone (non corrosion zone), while simultaneously acting as a physical barrier between the copper and the environment. For its effect to be adequate on the material there are two fundamental conditions, the oxide-reductive potential must be high and there should be minimal porosity.
To achieve this goal, a detailed study of electrodeposition has been carried out, using different techniques, and adjusting the different parameters such as environmental composition and potentials or currents applied. The polymer deposited copper was then tested by submerging it in a solution of NaCl, simulating sea water, which is one of the most corrosive environments there are, since it contains large numbers of chloride ions.
These ions are responsible for an extremely localised form of corrosion that leads to the creation of small holes in the metal, known as pitting. The study of the behaviour of these materials had led to the conclusion that by tuning the different parameters, a thin film can be created that withstands the attack of this harsh environment for at least a month.
A new tool for discovering nanoporous materials
23.05.2017 | Ecole Polytechnique Fédérale de Lausanne
Did you know that packaging is becoming intelligent through flash systems?
23.05.2017 | Heraeus Noblelight GmbH
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy