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dc.rights.licenseRestricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.
dc.contributorDuquette, D. J.
dc.contributor.authorCalebrese, Steven
dc.date.accessioned2021-11-03T08:04:12Z
dc.date.available2021-11-03T08:04:12Z
dc.date.created2014-01-16T11:57:58Z
dc.date.issued2013-08
dc.identifier.urihttps://hdl.handle.net/20.500.13015/963
dc.descriptionAugust 2013
dc.descriptionSchool of Engineering
dc.description.abstractThin Film samples were exposed to a single drop of 0.1 N and 1 N aqueous sulfuric acid solutions at temperatures between 25° C and 92° C. It was optically observed that a white filmed appeared on the surface as a reaction product. At both concentrations, increases in temperature lead to an increase in reaction rate for droplet exposed samples. These reactions were found to follow Arrhenius behavior. The 1 N solution activation energy of film appearance was found to be 69100 J, and for 0.1 N solution was found to be 48300 J. It was expected that an increase in concentration would lead to an increase in reaction rate as well. However for single droplet exposure it was found that lower concentrations resulted in increased reaction rate. This may be due to the difference in interfacial energy between the solution and PZT surface as a result of the concentration of sulfuric acid.
dc.description.abstractSuggested future work and analytical techniques are also proposed to fully characterize the dissolution kinetics of PZT in aqueous sulfuric acid. These include the characterization of the interfacial energy between solution droplets and PZT surface, potentiostatic bath exposure of thin films in which the potential on the substrate is fixed, solution analysis via ICP-MS or other alternative, and the comparison of dissolution rate between bulk PZT and thin film PZT to determine the effect pinholes may have on the reaction. Various temperatures and acid concentrations are also proposed in order to fully characterize the Arrhenius behavior of reaction rate.
dc.description.abstractThe potential on the substrate during bath exposure was between -0.22 V and 0.1 V. As a ferroelectric, PZT is expected to spontaneously polarize and variations in potential are expected. The value of -0.22 V corresponds to the potential of a normal hydrogen electrode, the conditions that would be found if the platinum layer were exposed, which could occur due to pinholes in the sample. The potential on the substrate and time of exposure were not found to correspond to dissolution depth using XPS depth profiling. A proposed reason is that attack was not found to be uniform across the surface, most likely as a result of high energy regions such as pinholes in the PZT film.
dc.description.abstractUsing XPS and XRD characterization techniques, PbSO4 was found to be one reaction product of both the PZT bulk sample exposed to a bath of solution, and thin film samples exposed to a single droplet of solution. Other reaction products were not able to be identified using the analysis techniques in this study, because the reaction products of zirconium and titanium are believed to take the form of ions in solution. While XPS confirmed their elemental presence in solution after evaporation, analysis of the solution itself was never conducted.
dc.description.abstractWith the recent interest for PZT use as a self-powered nanonsensor in extreme environments, such as an oil well, it is important to ensure the stability of the material under these conditions. Oil wells are known for being extremely caustic, with high temperature, low pH and high pressures. It has been shown that in the presence of sulfuric acid PZT is subject to chemical attack. This study attempts to identify the effects that pH and temperature have on the rate of the reaction.
dc.description.abstractSulfuric acid was used as a proxy for the H2S environment found in oil wells. Exposure of bulk PZT and thin film specimens to H2S was studied. PZT 52/48 thin films were fabricated via the sol gel process. PZT was exposed to both single drops of aqueous sulfuric acid and submerged in a bath of solution. During bath exposure potential on the substrate surface of thin film samples was recorded using a voltmeter vs. and Ag/AgCl reference electrode.
dc.language.isoENG
dc.publisherRensselaer Polytechnic Institute, Troy, NY
dc.relation.ispartofRensselaer Theses and Dissertations Online Collection
dc.subjectMaterials science and engineering
dc.titleDissolution of PZT 52/48 in aqueous sulfuric acid environments
dc.typeElectronic thesis
dc.typeThesis
dc.digitool.pid170067
dc.digitool.pid170068
dc.digitool.pid170069
dc.rights.holderThis electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
dc.description.degreeMS
dc.relation.departmentDept. of Materials Science and Engineering


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