TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - DELTA - Investigation of corrosion and microbially influenced corrosion processes by means of X-Ray absorption spectroscopy N2 - Alloys relevant for corrosion research are inherently complex in chemical composition and microstructure. Their local surface chemistry differs significantly from the bulk composition and their surfaces are subjected to ever changing environmental conditions. Thus, a thorough understanding of the mechanisms leading to material degradation and failure requires a detailed characterisation of the initial and final states as well as an adequate monitoring of the relevant properties as a function of time. Moreover, corrosion products tend to oxidize in contact with the atmosphere. Microbially influenced corrosion (MIC) poses a particular challenge regarding the experimental methods that can be used for the investigations. The use of highly sensitive methods of ultra-high vacuum surface analysis requires the removal of the biofilm, which leads to significant changes in the interfacial chemistry. In recent projects we applied X-ray absorption near edge spectroscopy (XANES) to investigate mechanisms of aqueous corrosion, high temperature corrosion and MIC processes of stainless steel and multi-principal element alloys (MPEAs). By combining in situ XANES studies on model thin films with ex situ XANES analysis of technical samples we aimed to obtain a holistic understanding of degradation processes. In this presentation we will summarize our results on the application of XANES to corrosion and MIC research with two case studies. In the first case study, in situ and ex situ XANES were used for the investigation of aqueous and high-temperature corrosion processes of alloys from FeNiCr-Mn MPEA family to clarify the role of Mn in determining the corrosion resistance and passive film formation. Our results indicate that Mn plays a major role in suppressing Fe oxidation. In the second example we have shown by means of in situ and ex situ XANES analysis that cultivation of metal reducing bacteria (MRB) in abundance of Fe(III) ions leads to a significant increase in electrochemical activity and thus, to an accelerated corrosion of the metallic substrate. This implies that bacterial colonies released from active corrosion sites might show a preconditioning effect and pose a higher corrosion risk. T2 - eMRS 2024 Spring Meeting CY - Strasbourg, France DA - 27.05.2024 KW - Corrosion KW - XANES KW - MIC KW - Multi-principal element alloys PY - 2024 AN - OPUS4-62636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Almalla, A. A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia T1 - In Situ Atomic Force Microscopy Analysis of the Corrosion Processes at the Buried Interface of an Epoxy-like Model Organic Film and AA2024-T3 Aluminum Alloy N2 - The application of characterization methods with high spatial resolution to the analysis of buried coating/metal interfaces requires the design and use of model systems. Herein, an epoxy-like thin film is used as a model coating resembling the epoxy-based coatings and adhesives widely used in technical applications. Spin coating is used for the deposition of a 30 nm-thin bilayer (BL) composed of poly-(ethylenimine) (PEI) and poly[(o-cresyl glycidyl ether)-co-formaldehyde] (CNER). Fourier-transform infrared spectroscopy (FTIR) results confirm that the exposure of coated AA2024-T3 (AA) samples to the corrosive electrolyte solution does not cause the degradation of the polymer layer. In situ atomic force microscopy (AFM) studies are performed to monitor local corrosion processes at the buried interface of the epoxy-like film and the AA2024-T3 aluminum alloy surface in an aqueous electrolyte solution. Hydrogen evolution due to the reduction of water as the cathodic corrosion reaction leads to local blister formation. Based on the results of the complementary energy-dispersive X-ray spectroscopy (EDX) analysis performed at the same region of interest, most of the hydrogen evolved originates at the vicinity of Mg-containing intermetallic particles. KW - Scanning Kelvin probe force microscopy KW - Aluminum alloys KW - Buried interfaces KW - In situ atomic force microscopy KW - Local corrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546932 DO - https://doi.org/10.1002/adem.202101342 SN - 1438-1656 SP - 1 EP - 9 PB - Wiley VHC-Verlag AN - OPUS4-54693 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wetzel, Annica A1 - von der Au, Marcus A1 - Dietrich, P. M. A1 - Radnik, Jörg A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia T1 - The comparison of the corrosion behavior of the CrCoNi medium entropy alloy and CrMnFeCoNi high entropy alloy N2 - This work presents the determination of the corrosion characteristics of CrCoNi (medium entropy alloy) and CrMnFeCoNi (high entropy alloy) in 0.1 M NaCl and 0.1 M H2SO4. The morphology and chemical composition of the oxide layers formed on CrCoNi and CrMnFeCoNi were comparatively analyzed by scanning Kelvin probe microscopy (SKPFM) and scanning electron microscopy (SEM) and supported with chemical analysis by means of inductively coupled plasma mass spectrometry (ICP-MS) and X-Ray photoelectron spectroscopy (XPS). The analysis of the 3p core level peaks showed that the oxide layer (native and after anodic passivation) on CrCoNi consisted mainly of Cr oxides, while the oxide layer on CrMnFeCoNi was primarily composed of a mixture of Cr and Fe oxides. In addition, XPS was utilized to assess the oxide layer thicknesses. These results were compared to the thicknesses obtained by means of electrochemical impedance spectroscopy (EIS), with both approaches yielding values up to about 4 nm depending on the electrolyte and the alloy. Cyclic polarization measurements indicated superior corrosion resistance of CrCoNi in both aqueous environments compared to CrMnFeCoNi, as well as to AISI 304 stainless steel. KW - Medium entropy alloy KW - High entropy alloy KW - SKPFM KW - XPS KW - Passivation KW - Corrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559902 DO - https://doi.org/10.1016/j.apsusc.2022.154171 SN - 0169-4332 VL - 601 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-55990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Almalla, A. A1 - Hertwig, Andreas A1 - Fischer, Daniel A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia T1 - Development of layer-by-layer assembled thin coatings on aluminium alloy AA2024-T3 for high resolution studies of local corrosion processes N2 - The aim of this study is to develop nanometer-thin epoxy-based films on aluminium alloy AA2024-T3 as a model coating system for high resolution corrosion studies. Spin coating was used for the layer-by-layer (LbL) deposition of poly-(ethylenimine) (PEI) and poly([o-cresyl glycidyl ether]-co-formaldehyde) (CNER) bilayers. The film chemistry and the cross-linking process were characterized by means of Fourier-transform infrared spectroscopy (FTIR). Ellipsometric data confirmed the linear increase of film thickness. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) results indicate the improvement of the film barrier properties with increasing film thickness. Mapping of the topography and the volta potential was performed by means of scanning Kelvin probe force microscopy (SKPFM). The results indicate the presence of a homogeneous film structure, while the intermetallic phases can still be identified below the coating. The SKPFM Analysis confirmed that the model films are suitable for investigation of corrosion processes at the coating/metal interface. KW - Spectroscopy KW - Coatings KW - Electrochemistry KW - Microscopy KW - Resins PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514627 DO - https://doi.org/10.1002/app.49826 SN - 0021-8995 VL - 137 IS - 48 SP - e49826-1 EP - e49826-9 PB - Wiley CY - New York, NY AN - OPUS4-51462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wetzel, Annica A1 - Morell, Daniel A1 - von der Au, Marcus A1 - Wittstock, Gunther A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia T1 - Transpassive Metal Dissolution vs. Oxygen Evolution Reaction: Implication for Alloy Stability and Electrocatalysis T1 - Transpassive Metallauflösung vs. Sauerstoffentwicklung: Auswirkungen auf Legierungsstabilität und Elektrokatalyse N2 - Multi-principal element alloys (MPEAs) are gaining interest in corrosion and electrocatalysis research due to their electrochemical stability across a broad pH range and the design flexibility they offer. Using the equimolar CrCoNi alloy, we observe significant metal dissolution in a corrosive electrolyte (0.1 M NaCl, pH 2) concurrently with the oxygen evolution reaction (OER) in the transpassive region despite the absence of hysteresis in polarization curves or other obvious corrosion indicators. We present a characterization scheme to delineate the contribution of OER and alloy dissolution, using scanning electrochemical microscopy (SECM) for OER-onset detection, and quantitative chemical analysis with inductively coupled-mass spectrometry (ICP-MS) and ultraviolet visible light (UV-Vis) spectroscopy to elucidate metal dissolution processes. In-situ electrochemical atomic force microscopy (EC-AFM) revealed that the transpassive metal dissolution on CrCoNi is dominated by intergranular corrosion. These results have significant implications for the stability of MPEAs in corrosion systems, emphasizing the necessity of analytically determining metal ions released from MPEA electrodes into the electrolyte when evaluating Faradaic efficiencies of OER catalysts. The release of transition metal ions not only reduces the Faradaic efficiency of electrolyzers but may also cause poisoning and degradation of membranes in electrochemical reactors. N2 - Multi-Hauptelement-Legierungen (MPEAs) gewinnen in der Korrosions- und Elektrokatalyseforschung aufgrund ihrer elektrochemischen Stabilität über einen breiten pH-Bereich und der Vielfalt der möglichen chemischen Zusammensetzungen zunehmend an Interesse. In unseren Untersuchungen mit der äquimolaren CrCoNi-Legierung in einem sauren Elektrolyten (0.1 M NaCl, pH 2) beobachteten wir eine signifikante Metallauflösung, die mit der Sauerstoffentwicklungsreaktion (OER) im transpassiven Bereich einhergeht, obwohl in zyklischen Polarisationskurven keine Hysterese auftrat oder andere offensichtliche Korrosionsindikatoren vorlagen. In diesem Artikel wird ein Charakterisierungskonzept eingeführt, dass die Beiträge der OER und der Legierungsauflösung differenziert. Hierfür kommt die elektrochemische Rastermikroskopie (SECM) zum Nachweis des Beginns der OER und die quantitative chemische Analyse mit induktiv gekoppelter Massenspektrometrie (ICP-MS) und UV/Vis-Spektrometrie zur Aufklärung der Metallauflösungsprozesse zum Einsatz. Die elektrochemische In situ-Atomkraftmikroskopie (EC-AFM) zeigte, dass die intergranulare Korrosion der dominierende Mechanismus der transpassive Metallauflösung von CrCoNi ist. Diese Ergebnisse besitzen erhebliche Auswirkungen für die Beurteilung der Stabilität von MPEAs in Korrosionssystemen und der Stromausbeute von OER-Katalysatoren auf der Basis von MPEAs. Die Daten unterstreichen die Notwendigkeit der analytischen Bestimmung von Metallionen, die von MPEA-Elektroden freigesetzt werden. Die Freisetzung von Übergangsmetallionen verringert nicht nur die Stromausbeute von Elektrolyseuren, sondern kann zu einer Schädigung von Membranen in elektrochemischen Reaktoren führen. KW - Transpassive dissolution KW - Corrosion KW - Multi-prinicpal element alloys (MPEAs) KW - Passivation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597045 DO - https://doi.org/10.1002/anie.202317058 SP - 1 EP - 8 PB - Wiley VHC-Verlag AN - OPUS4-59704 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Neue Projekte im Bereich Biokorrosion: Spektro-elektrochemische Untersuchungen der Biofilmbildung und MIC auf Metalloberflächen N2 - In this presentation, new projects of FB 6.2 focussing on the Analysis of microbiologically influenced corrosion (MIC) have been summarized. T2 - Sitzung der DECHEMA-GfKORR-Fachgruppe: Mikrobielle Materialzerstörung und Materialschutz CY - DECHEMA Forschungsinstitut, Frankfurt am Main, Germany DA - 30.05.2016 KW - MIC KW - Microbiologically influenced corrosion KW - Local electrochemical methods KW - Spectroelectrochemistry PY - 2016 AN - OPUS4-38200 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Material Acceleration Platforms of BAM (MAPs@BAM) N2 - Material Acceleration Platforms (MAPs) represent a transformative approach to the development of resilient and sustainable technology value chains. These platforms can identify candidate chemistries and structures via simulations, and database searches and leverage machine learning-based rapid screening to accelerate the discovery and deployment of novel materials, thereby addressing critical challenges in modern technology sectors. Incorporating high-fidelity advanced characterization in the early phases of material development is crucial for early de-risking. Advanced characterization techniques, such as X-ray diffraction, advanced electrochemical and spectroscopic techniques provide comprehensive insights into the structural, chemical, and physical properties of materials. Long-term testing further contributes to the de-risking process by evaluating the durability and stability of materials under various environmental and operational conditions. This presentation will briefly summarize how we address these issues at MAPs@BAM and provide deep-dives on best practices. As the demand for advanced materials continues to grow, MAPs will play an increasingly vital role in driving technological advancements and addressing global challenges. T2 - FutureLabsLive Basel CY - Basel, Switzerland DA - 25.06.2024 KW - MAPs@BAM PY - 2024 AN - OPUS4-62643 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Material Acceleration Platforms of BAM (MAPs@BAM) N2 - Material Acceleration Platforms (MAPs) represent a transformative approach to the development of resilient and sustainable technology value chains. These platforms can identify candidate chemistries and structures via simulations, and database searches and leverage machine learning-based rapid screening to accelerate the discovery and deployment of novel materials, thereby addressing critical challenges in modern technology sectors. Incorporating high-fidelity advanced characterization in the early phases of material development is crucial for early de-risking. Advanced characterization techniques, such as X-ray diffraction, advanced electrochemical and spectroscopic techniques provide comprehensive insights into the structural, chemical, and physical properties of materials. Long-term testing further contributes to the de-risking process by evaluating the durability and stability of materials under various environmental and operational conditions. This presentation will briefly summarize how we address these issues at MAPs@BAM and provide deep-dives on best practices. As the demand for advanced materials continues to grow, MAPs will play an increasingly vital role in driving technological advancements and addressing global challenges. T2 - EERA-JPNM Days Workshop (EERA-Joint Programme on Nuclear Materials) CY - Online meeting DA - 29.05.2024 KW - MAPs@BAM PY - 2024 AN - OPUS4-62642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - The interplay of anodic passivation and oxygen evolution on multi-principal element alloys (MPEAs) N2 - Multi-principal element alloys (MPEAs) are of great academic and industrial interest as emerging materials for engineering applications as well as potential electrode materials in energy conversion and storage. Several MPEAs have been studied for their general corrosion behavior, but studies on their dissolution in the high anodic “transpassive” potentials relevant for oxygen evolution reaction (OER) and local corrosion behavior remained scarce. In this project we have investigated CrMnFeCoNi, FeCrNi and CrCoNi MPEAs in terms of their transpassive behavior in NaCl electrolytes and artificial seawater [1, 2]. We introduced a characterization procedure to distinguish the individual contributions of oxygen evolution reaction (OER) and alloy dissolution [2]. This scheme utilizes scanning electrochemical microscopy (SECM) for detecting the onset of OER and employs quantitative chemical analysis methods, namely inductively coupled mass spectrometry (ICP-MS) and ultraviolet-visible light (UV-Vis) spectroscopy, to elucidate the processes of metal dissolution. In-situ atomic force microscopy (AFM) and scanning Kelvin probe force microscopy (SKPFM) were used to analyze the corrosion morphology and surface potentials before, during, and after passivity breakdown. Our results clearly demonstrate the superior corrosion behavior of CrCoNi and FeCrNi MPEA in comparison to the CrFeMnCoNi HEA, as well as AISI 304 stainless steel. We have observed that significant OER occurs in parallel with metal dissolution on the CrCoNi and FeCrNi MPEA surfaces during anodic polarization at potentials relevant to water electrolysis. Most importantly, our findings underscore the necessity of analyzing metal ions dissolved into the electrolyte to accurately assess the Faradaic efficiencies of non-noble metal OER electrocatalysts. The presentation will summarize our characterization procedure and give an overview on the key properties of the studied MPEAs.  [1] A. Wetzel, M. von der Au, P.M. Dietrich, J. Radnik, O. Ozcan, J. Witt, The comparison of the corrosion behavior of the CrCoNi medium entropy alloy and CrMnFeCoNi high entropy alloy, Appl. Surf. Sci., 601 (2022) 154171. [2] A. Wetzel, D. Morell, M. von der Au, G. Wittstock, O. Ozcan, J. Witt, Transpassive Metal Dissolution vs. Oxygen Evolution Reaction: Implication for Alloy Stability and Electrocatalysis, Angew. Chem. Int. Ed. Engl., n/a (2024) e202317058. T2 - ECASIA 2024 CY - Gothenburg, Sweden DA - 09.06.2024 KW - CCMat KW - Corrosion KW - Electrocatalysis KW - Oxygen evolution reaction PY - 2024 AN - OPUS4-62637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - State-of-the-art in map development: Best practices for application in nuclear materials N2 - Material Acceleration Platforms (MAPs) represent a transformative approach to the development of resilient and sustainable technology value chains. These platforms can identify candidate chemistries and structures via simulations, and database searches and leverage machine learning-based rapid screening to accelerate the discovery and deployment of novel materials, thereby addressing critical challenges in modern technology sectors. Incorporating high-fidelity advanced characterization in the early phases of material development is crucial for early de-risking. Advanced characterization techniques, such as X-ray diffraction, advanced electrochemical and spectroscopic techniques provide comprehensive insights into the structural, chemical, and physical properties of materials. Long-term testing further contributes to the de-risking process by evaluating the durability and stability of materials under various environmental and operational conditions. This presentation will briefly summarize how we address these issues at MAPs@BAM and provide deep-dives on best practices. As the demand for advanced materials continues to grow, MAPs will play an increasingly vital role in driving technological advancements and addressing global challenges. T2 - CONNECT-NM European Partnership Kick-off Meeting CY - Madrid, Spain DA - 02.10.2024 KW - MAPs@BAM KW - Corrosion PY - 2024 AN - OPUS4-62646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Material Acceleration Platforms of BAM (MAPs@BAM) N2 - Material Acceleration Platforms (MAPs) represent a transformative approach to the development of resilient and sustainable technology value chains. These platforms can identify candidate chemistries and structures via simulations, and database searches and leverage machine learning-based rapid screening to accelerate the discovery and deployment of novel materials, thereby addressing critical challenges in modern technology sectors. Incorporating high-fidelity advanced characterization in the early phases of material development is crucial for early de-risking. Advanced characterization techniques, such as X-ray diffraction, advanced electrochemical and spectroscopic techniques provide comprehensive insights into the structural, chemical, and physical properties of materials. Long-term testing further contributes to the de-risking process by evaluating the durability and stability of materials under various environmental and operational conditions. This presentation will briefly summarize how we address these issues at MAPs@BAM and provide deep-dives on best practices. As the demand for advanced materials continues to grow, MAPs will play an increasingly vital role in driving technological advancements and addressing global challenges. T2 - International Cooperation on Innovative Materials for Energy Workshop CY - Brussels, Belgium DA - 19.04.2024 KW - MAPs@BAM PY - 2024 AN - OPUS4-62641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wurzler, Nina A1 - Özcan Sandikcioglu, Özlem T1 - The effect of flavins on the corrosion properties of stainless steels during initial stages of microbiologically influenced corrosion N2 - Microbiologically influenced corrosion (MIC) on steel occurs where the presence and activity of microbes change the localized conditions on the surface of a metal substrate. For instance, metal reducing bacteria (MRB) are capable of utilizing metal compounds in the passive layer on stainless steel as electron acceptors during their metabolism. This weakening of the passive film not only leads to an acceleration of the general corrosion processes, but also increases the susceptibility of stainless steels to pitting corrosion. Even though the electron transfer mechanisms are not yet fully understood, recent research shows that the secretion of electron shuttles like flavins contribute significantly to the extracellular electron transfer (EET). Electron shuttle molecules like riboflavin (RB) or flavin mononucleotide (FMN) are secreted by MRB after the transition from planktonic to sessile mode and exist in the biofilm at low concentrations. Therefore, they are precise early phase indicators of bacterial settlement. This project aims at clarifying the electrochemical interaction mechanisms of MRB with stainless steel surfaces, with a special focus on the role of the extracellular redox molecules. The analysis of corrosion processes as a function of chloride and flavin concentration have been performed by means of electrochemical methods. Due to the differences in their chemical structure, FMN and RB have shown significant differences in terms of their adsorption behavior and the stability of the formed films, which directly influences the electron transfer processes. Therefore, Electrochemical Quartz Crystal Microbalance (eQCM) studies have been performed on sputtered FeCr electrodes to investigate the adsorption/desorption kinetics of flavins. The results of electrochemical studies are complemented by the analysis of the changes in the passive film chemistry and the chemical composition of the adsorbed films by means of Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) and X-ray photoelectron spectroscopy (XPS). Changes in surface morphology have been investigated by means of Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM).The presentation will summarize our results on the degradation mechanisms of passive films on stainless steel surfaces in the presence of flavins and provide useful insights from a fundamental aspect for the understanding of the initial stages of microbiologically influenced corrosion. T2 - 17TH EUROPEAN CONFERENCE ON APPLICATIONS OF SURFACE AND INTERFACE ANALYSIS CY - Montpellier, France DA - 24.09.2017 KW - Flavins KW - Microbiologically influenced corrosion KW - Stainless steel KW - MIC PY - 2017 AN - OPUS4-43402 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Coupled electrochemical, microscopic and spectroscopic techniques for the analysis of local corrosion and mic processes N2 - Summary of the research topics of the division 6.2 and recent results T2 - HZDR-IRE Institutscolloquium CY - Dresden, Germany DA - 24.09.2019 KW - MIC KW - Localised corrosion KW - Corrosion monitoring KW - Biofilmbildung KW - Atomic Force Microscopy (AFM) PY - 2019 AN - OPUS4-50295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Özcan Sandikcioglu, Özlem T1 - Chemical and electrochemical interaction mechanisms of metal-reducing bacteria with gold surfaces N2 - Bacterial biofilms are considered one of the salient contributing factors to the deterioration of metals and their alloys, occurring in virtually all environments and across various industrial systems. Considering the sheer magnitude of detrimental effects, it is of pertinent interest to elucidate the interaction mechanisms of sessile bacteria with metal and metal oxide surfaces to facilitate the development of efficient antifouling strategies. A common constituent of microbial communities within aquatic and sedimentary settings, the Shewanella genus consists of facultatively aerobic, Gram-negative bacterium which exhibit exceptional plasticity in respiratory capacities. During aerobic conditions, Shewanella utilizes oxygen as a terminal electron acceptor; conversely, under anaerobic conditions, it is able to undertake respiration by reducing alternative terminal electron acceptors such as oxidized metals via extracellular electron transfer mechanisms not yet thoroughly discerned. The aim of this work is to explicate the mechanisms governing the initial bacterial adhesion and subsequent biofilm formation on metallic surfaces. To investigate this dynamic interplay, a combined approach has been followed which couples surface enhanced Raman spectroscopy (SERS) with electrochemical techniques using Shewanella sp. model biofilms. Gold nano-islands deposited on thin glass slides have been chosen as inert model substrates with good uniformity and high surface enhancement factor. Furthermore, the utilization of gold as substrate material not only allowed the differentiation of the sole effect of substrate polarization on bacterial attachment but also enabled a precise adjustment of the surface chemistry and surface energy by means of surface functionalization with organothiol self-assembled monolayers. The results present the correlation of the primary settlement rate of bacteria on metallic substrates with the environmental parameters such as electrolyte composition and pH as well as surface-related properties like hydrophobicity/hydrophilicity and polarization. With the overall strategic goal of transferring this methodology to technical systems the results provide the fundamental basis for the bottom-up design of anti-fouling surfaces. T2 - Electrochemistry 2016 CY - Göslar, Germany DA - 26.09.2016 KW - Bacterial biofilms KW - Electrochemistry KW - Microbiology KW - Surface enhanced Raman spectroscopy KW - Raman spectroscopy KW - Microbiologically induced corrosion KW - Anti-fouling KW - Shewanella KW - Biocorrosion PY - 2016 AN - OPUS4-47243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -