A5035851839- Electrocatalysts for Energy Conversion
- Catalytic Processes in Materials Science
- Electrochemical Analysis and Applications
- nanoparticles nucleation surface interactions
- Advanced Chemical Physics Studies
- Catalysis and Oxidation Reactions
- Molecular Junctions and Nanostructures
- Advancements in Battery Materials
- CO2 Reduction Techniques and Catalysts
- Ionic liquids properties and applications
- TiO2 Photocatalysis and Solar Cells
- Gas Sensing Nanomaterials and Sensors
- ZnO doping and properties
- Photochromic and Fluorescence Chemistry
- Electronic and Structural Properties of Oxides
- Photochemistry and Electron Transfer Studies
- Advanced Photocatalysis Techniques
- Porphyrin and Phthalocyanine Chemistry
Friedrich-Alexander-Universität Erlangen-Nürnberg
2018-2022
Abstract Cobalt oxide is a promising earth abundant electrocatalyst and one of the most intensively studied oxides in electrocatalysis. In this study, structural dynamics well‐defined cobalt nanoislands (NIs) on Au(111) are investigated situ under potential control. The samples prepared ultra‐high vacuum system characterized using scanning tunneling microscopy (STM). After transfer into electrochemical environment, structure, mobility, dissolution via (EC) STM, cyclic voltammetry, EC on‐line...
We have explored the stability, structure, and chemical transformations of atomically defined Co3O4(111) thin films under electrochemical conditions. The well-ordered were prepared on an Ir(100) single crystal ultrahigh vacuum (UHV) conditions subsequently transferred characterized in environment by means cyclic voltammetry (CV), scanning flow cell inductively coupled plasma mass spectrometry (SCF-ICP-MS), infrared reflection absorption spectroscopy (EC-IRRAS). found that are stable...
Model studies at complex, yet well-defined electrodes can provide a better understanding of electrocatalytic reactions. New experimental devices are required to prepare such model electrocatalysts with atomic-level control. In this work, we discuss the design new setup, which enables preparation in ultra-high vacuum (UHV) using full portfolio surface science techniques. The setup allows for direct transfer samples from UHV and immersion into electrolyte without contact air. As special...
We have prepared model systems for Pt–Ga supported catalytically active liquid metal solutions (SCALMS) by physical vapor deposition of Pt and Ga onto highly oriented pyrolytic graphite (HOPG). Prior to deposition, the HOPG support was modified Ar+ bombardment. In this work, we focus on stability deposits toward agglomeration, which is a critical challenge in application. Specifically, study behavior catalysts ultrahigh vacuum (UHV) under near ambient pressure (NAP) conditions at different...
Dissolution and redeposition processes determine the stability of electrode materials. In this work, we address these in situ during oxidation subsequent reduction Au(111) electrodes an acidic electrolyte (0.1 M H2SO4). We used complementary techniques, namely, electrochemical scanning tunneling microscopy (EC-STM) on-line inductively coupled plasma mass spectrometry (ICP–MS). observed that rate distinctively influences dissolution resulting morphology surface. Slow leads to formation...
Electronic metal–support interactions play a key role in the design of heterogeneous catalysts, as they provide tool for tuning catalytic properties and enhancing catalyst stability. In this work, we explore electrocatalysis using model approach. We investigate adsorption reaction behavior atomically defined Pt/Co3O4 catalysts under ultrahigh vacuum (UHV) electrochemical conditions. The systems were prepared by physical vapor deposition (PVD) Pt onto well-ordered Co3O4(111) films on Ir(100),...
We have studied particle size effects on atomically-defined model catalysts both in ultrahigh vacuum (UHV) and under electrochemical (EC) conditions liquid electrolytes. The were prepared UHV by physical vapour deposition (PVD) of Pt onto an ordered Co3O4(111) film Ir(100), yielding nanoparticles (NPs) with average from 10 to 500 atoms per (0.8 3 nm). systems characterized using surface science methods including scanning tunnelling microscopy (STM), before transferring them out the into...
Achieving high stability of supported noble metal nanoparticles with respect to sintering is one the major challenges in electrocatalysis. In this study, we explored role metal–support interaction stabilizing morphology a well-defined model electrode consisting Pt on well-ordered Co3O4(111) films Ir(100). We employed X-ray photoelectron spectroscopy coupled an electrochemical cell analyze changes oxidation states both and support as function potential. found that immersion into aqueous...
Solid catalysts with ionic liquid layers (SCILLs) have recently attracted a lot of attention, as the (IL) coating can give rise to drastically improved selectivity. Here, we studied interaction IL 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)-imide [C4C1Pyr][NTf2] Pt(111) and Pt nanoparticles (NPs) on highly oriented pyrolytic graphite under ultrahigh vacuum conditions. The film NPs consists strongly bound monolayer weakly bulk phase. In monolayer, [NTf2]− adopts cis...
Molecular solar thermal (MOST) systems open application fields for energy conversion as they combine conversion, storage, and release in one single molecule. For release, catalysts must be controllable, selective, stable over many operation cycles. Here, we present a MOST/catalyst couple, which combines all these properties. We explore storage tailor-made MOST system (cyano-3-(3,4-dimethoxyphenyl)-norbornadiene/quadricyclane; NBD′/QC′) the heterogeneously catalyzed at Au(111) surface. By...
Particle size and shape effects control the oxidation behavior of nanostructured electrocatalysts. We investigated state Pd nanoparticles supported on Ar+-sputtered highly oriented pyrolytic graphite (HOPG) well-ordered Co3O4(111) films Ir(100) as a function electrode potential by means synchrotron radiation photoelectron spectroscopy coupled with an ex situ emersion electrochemical (EC) cell. Scanning tunneling microscopy revealed growth hemispherical flat HOPG Co3O4(111), respectively. The...
Solid catalysts with ionic liquid layers (SCILLs) are heterogeneous coated a thin layer of an (IL) to improve their selectivity. In this study, we investigated the interplay room-temperature IL 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide [C4C1Pyr][NTf2] transition metal surfaces both Pd(111) single crystals and Pd nanoparticles (NPs) supported on highly oriented pyrolytic graphite (HOPG). To end, combine theoretical insights obtained by density functional theory (DFT)...
Porphyrins are large organic molecules that interesting for different applications, such as photovoltaic cells, gas sensors, or in catalysis. For many of these the interactions between adsorbed and surfaces play a crucial role. Studies porphyrins on typically fall into one two groups: (1) evaporation onto well-defined single-crystal under well-controlled ultrahigh vacuum conditions (2) more application-oriented wet chemical deposition less high surface area ambient conditions. In this study,...