31 research outputs found
Makro-, mikro- és nanoelektrokémia integrációja = Integration of macro, micro and nanoelectrochemistry
A pályázat futamidejének végére létrejött egy pásztázó elektrokémiai mikroszkóp mérőegyüttes, amellyel a mezoszkopikus léptékű felületvizsgálatban elvileg elválasztható a topológiai és a kémiai heterogenitás, a többi felületvizsgálati módszerhez képest egyedülálló módon. A makroszkopikus mérésekben elektrokémiai módszereket, az atomi felbontásúakban pásztázó alagút és atomi erőmikroszkópiát használtunk. A műszeregyüttessel a mezoszkopikus mérettartományban fejlesztés alatt álló szuperkondenzátor-struktúrákat, önszerveződő monorétegeket és lokális korróziós jelenségeket vizsgáltunk. | At the end of the project duration, a scanning electrochemical microscope setup, complete with auxiliary units, was implemented by which one theoretically can distinguish between topological and chemical heterogeneity – a unique possibility as compared to the other surface analysis tools. For the macroscopic measurements electrochemical methods were used while atomic scale measurements were implemented by scanning tunnelling and atomic force microscopy. The setup was used to investigate supercapacitor structures under development, self-organised monolayers and localised corrosion phenomena
Funkcionális nanoszerkezetű bevonatok = Functional nanostructured layers
A projekt keretĂ©ben tanulmányoztuk nanostrukturált bevonatok, nanokompozitok Ă©s önszervezĹ‘dĂ©ssel kialakĂtott rĂ©tegek fizikai Ă©s kĂ©miai tulajdonságait, vizsgáltuk a felĂĽletmĂłdosĂtás kinetikáját Ă©s hatásmechanizmusát. Megvizsgáltuk ezen mĂłdszerek alkalmazhatĂłságát funkcionális bevonatok előállĂtására. Eljárást dolgoztunk ki Ăşj tĂpusĂş felĂĽletmĂłdosĂtásra acĂ©l Ă©s vas felĂĽletĂ©n, amelyek alkalmasak korrĂłziĂłvĂ©dĹ‘ rĂ©tegkĂ©nt törtĂ©nĹ‘ alkalmazásra. Optimalizáltuk a rĂ©tegkĂ©pzĂ©s során alkalmazott kĂsĂ©rleti körĂĽlmĂ©nyeket. MĂłdszert dolgoztunk ki mágneses Fe nanoporok előállĂtására, valamint vas nanorĂ©szecskĂ©k fotoaktĂv Ă©s szigetelĹ‘ tulajdonságĂş ZnO nanorĂ©teggel törtĂ©nĹ‘ bevonására. LĂ©zeroptikai Ă©s számĂtĂłgĂ©pes szimuláciĂłs mĂłdszert dolgoztunk ki vĂzfelszĂni nanorĂ©szecskĂ©k kontakt nedvesedĂ©sĂ©nek jellemzĂ©sĂ©re. NanorĂ©szecskĂ©k szabályozott szerkezetű LB-rĂ©tegeit állĂtottuk elĹ‘, melyek alkalmasak antireflexiĂłs bevonatok előállĂtására Ă©s antireflexiĂłs hatás szabályozására. Nanoszerkezetű Ni bevonatokat állĂtottunk elĹ‘ pulzálĂł elektrokĂ©miai eljárással Watt? s tĂpusĂş elektrolitbĂłl fĂ©mes Ă©s nem fĂ©mes hordozĂłra. FelĂĽletmĂłdosĂtott AFM szenzor segĂtsĂ©gĂ©vel az atomi erĹ‘ mikroszkĂłpia mĂłdszerĂ©n alapulĂł lokális felĂĽleti energia meghatározás egy Ăşj metodikáját dolgoztuk ki Ă©s alkalmaztuk kĂĽlönbözĹ‘ energiájĂş modellfelĂĽletek minĹ‘sĂtĂ©sĂ©re. | The aim of the project was to study the physical and chemical properties of nanostructured coatings, nanocomposites and self-assembled nanolayers. The possibilities to apply these methods for preparing functional coatings have been investigated. New surface modification methods for iron and steel have been developed, for anticorrosive purpose. The experimental conditions of layer formation have been optimised. Method for preparation of magnetic iron nanopowder, and coating of iron nanoparticules with fotoactive and isolating ZnO nanolayers have been elaborated. Laser-optical and computer simulation method has been developed to characterise the contact wettability of nanoparticules at water surface. LB-layers of nanoparticules with controlled structure have been prepared, which may be applied as antireflexive coating and control antireflexion effect. Nanostructured Ni coatings have prepared on metallic and non-metallic substrate by electrochemical pulse technique from Watt?s type electrolyte. A microscopic method based on surface modification of AFM tip has been developed for determining the local energy. An evaluation process has been established and its ability to determine the adhesion strength in nanoscale spatial variation has been demonstrated on model surfaces
Corrosion protection in sulfate medium by self-assemb films adsorbed on AA 2024 T3 aluminum alloy surface
Comportamento eletroquĂmico da cisteĂna e do difosfonato para o aço inoxidável 304 em HCl 1 mol L-1
Performance of primers containing polyphosphate-based ion-exchange pigments for the protection of galvanised steel
New corrosion inhibitors for evaporative cooling systems
Corrosion of heat exchangers and installations in evaporative cooling systems is a serious problem of industry, as it may lead to increased maintenance effort, damages, up to plant shut-down causing high cost. Furthermore, there may be a high environmental impact due to the discharge of blow-down water containing heavy metals or hazardous compounds, which may enter the water system via leakages.
State of the art corrosion inhibitor programs are based on phosphate, phosphonates, zinc and combinations thereof. Although generally satisfying control of corrosion can be achieved, all programs suffer more or less severe drawbacks, such as lack of biodegradability, content of heavy metals or necessity of pH control combined with acid dosage. Consequently, there is a need of corrosion inhibitors having an improved environmental profile and/or an improved performance. This paper shows the first results of two newly developed corrosion inhibitors. Both molecules are based on modified organic acids, free of heavy metals, one additionally doesn’t contain phosphorous.
Corrosion tests have been carried out with carbon steel specimen in dependence of inhibitor concentration, water composition and water temperature. Electrochemical methods, e.g. voltammetrie and polarization resistance, were applied as well as beaker tests and long term tests in cooling circuit simulating devices. Furthermore, the anti-scaling efficiency of the new inhibitors was studied.
The results of the corrosion tests clearly show an excellent efficiency of both substances, that meets the performance of commercially available corrosion inhibitors. In addition to this the phosphorous containing molecule shows a very good inhibition of calcium carbonate scaling, similar or even better compared to the performance of modern polycarboxylates. Thus, it could be the backbone of a complete treatment program for cooling systems. The second corrosion inhibitor could be applied in phosphorous and heavy metal free corrosion inhibition programs