FG Technische Chemie

54 Items

Recent Submissions
Experimental Activity Descriptors for Iridium-based Catalysts for the Electrochemical Oxygen Evolution Reaction (OER)

Spöri, Camillo Wolfgang ; Briois, Pascal ; Nong, Hong Nhan ; Reier, Tobias ; Billard, Alain ; Kühl, Stefanie ; Teschner, Detre ; Strasser, Peter (2019-06-13)

Recent progress in the activity improvement of anode catalysts for acidic electrochemical water splitting was largely achieved through empirical studies of iridium-based bimetallic oxides. However, practical, experimentally accessible, yet general predictors of catalytic OER activity are lacking. This study investigates iridium and iridium-nickel thin film model electrocatalysts for the OER and...

The Stability Challenges of Oxygen Evolving Catalysts: Towards a Common Fundamental Understanding and Mitigation of Catalyst Degradation

Spöri, Camillo Wolfgang ; Kwan, Jason Tai Hong ; Bonakdarpour, Arman ; Wilkinson, David P. ; Strasser, Peter (2017-05-04)

This review addresses the technical challenges, their scientific basis, as well as recent progress and the road ahead with respect to the stability and degradation of OER catalysts operating at electrolyzer anodes in acidic environments with an emphasis on MEA based operation. First, we start clarifying the complexity associated with the term “catalyst stability”, cover today’s performance targ...

Surface Plasmon Resonance Immunosensor for the Detection of Campylobacter jejuni

Masdor, Noor Azlina ; Altintas, Zeynep ; Tothill, Ibtisam E. (2017-05-16)

Campylobacteriosis is an internationally important foodborne disease caused by Campylobacter jejuni. The bacterium is prevalent in chicken meat and it is estimated that as much as 90% of chicken meat on the market may be contaminated with the bacterium. The current gold standard for the detection of C. jejuni is the culturing method, which takes at least 48 h to confirm the presence of the bact...

Structure-stability-activity studies on low Ir content mixed metal oxides for the electrochemical water oxidation in acidic media

Spöri, Camillo Wolfgang (2019)

Today, renewable energy power plants are being installed on an increasing scale, however, their growing capacity calls for reliable high-performance storage technologies to be developed simultaneously. PEM water electrolysis is one of the key emerging technologies for chemical energy storage in form of hydrogen, which, for example, can be used in fuel cells for transportation and reconversion t...

Untersuchung von Deflagrationen selbstzersetzlicher Feststoffe und Entwicklung einer neuartigen Prüfmethode zur Beurteilung der Deflagrationsfähigkeit in geschlossenen Systemen

Salg, Steffen (2019)

Das Deflagrationsverhalten selbstzersetzlicher fester Stoffe wurde bei unterschiedlichen Randbedingungen untersucht. Darüber hinaus wurde eine neue Prüfmethode entwickelt, mit welcher das Deflagrationsverhalten in geschlossenen Systemen beurteilt werden kann. Es wurden drei neue Messsysteme mit verschiedenen Volumina und Geometrien im Labormaßstab in Betrieb genommen. Die Verwendung der neuen M...

Metal-nitrogen-doped carbon (M-N-C) catalysts for the direct electrochemical reduction of CO2 to value-added chemicals and fuels

Ju, Wen (2019)

In the past decades, the surplus of atmospheric CO2 concentration has drawn tremendous political and scientific attention for its negative impacts, such as the greenhouse effect and ocean carbonation. To mitigate such CO2 issues, a combination of various strategies is required. The electrochemical CO2 reduction reaction (CO2RR) is a promising alternative to convert CO2 into carbon-based chemica...

Model-system studies on manganese oxide-based water oxidation catalysts made with atomic layer deposition

Plate, Paul (2019)

Climate change has become the main challenge of our society. Extensive CO2 emission due to fossil fuel combustion has to be minimized to prevent severe damages to the climate system. Hence, new and sustainable energy carriers have to be explored. Hydrogen can be produced in a sustainable manner, however, current processes are not yet economically viable. Photoelectrochemical water splitting is ...

Real-time imaging of activation and degradation of carbon supported octahedral Pt–Ni alloy fuel cell catalysts at the nanoscale using in situ electrochemical liquid cell STEM

Beermann, Vera ; Holtz, Megan E. ; Padgett, Elliot ; de Araujo, Jorge Ferreira ; Muller, David A. ; Strasser, Peter (2019-05-20)

Octahedrally shaped Pt–Ni alloy nanoparticles on carbon supports have demonstrated unprecedented electrocatalytic activity for the oxygen reduction reaction (ORR), sparking interest as catalysts for low-temperature fuel cell cathodes. However, deterioration of the octahedral shape that gives the catalyst its superior activity currently prohibits the use of shaped catalysts in fuel cell devices,...

Precious metal-free bifunctional catalysts for reversible seawater electrolyzers

Dresp, Sören (2019)

Regenerative hydrogen, which is produced by renewable electricity used in water electrolyzers, is considered as ideal energy carrier of the future. The selective splitting of seawater into oxygen and hydrogen seem to be a promising alternative compared to established water electrolysis technologies, which typically use highly purified water and electrolytes only. In addition, the back transform...

Pulsed laser deposition of efficient ternary metal oxide photoelectrodes

Kölbach, Moritz (2019)

Climate change, mainly driven by the combustion of fossil fuels releasing the greenhouse gas CO2, is a major threat to humanity and the ecosystems on our planet. To limit global warming, a transition towards a sustainable energy infrastructure based on renewable energies is essential. The storage of solar energy in the form of chemical bonds, in so-called solar fuels, is thereby believed to be ...

In situ studies of Pt nanoparticles on different supports for corrosion stable PEM fuel cell cathodes

Schmies, Henrike (2019)

Wasserstoffbrennstoffzellen bieten als elektrochemische Energiewandler die Möglichkeit, Wasserstoff aus erneuerbaren Resourcen als saubere und emissionsarme Energiequelle für elektrische Verbraucher, wie Elektromotoren, zu nutzen. Um eine konkurrenzfähige Alternative zu heutigen Verbrennungsmotoren in der Automobilindustrie darstellen zu können, müssen aber noch verschiedenste Hindernisse überw...

A new inductive-annealing dual electrochemical cell for crystal alloy and thin-film electrode voltammetry

Özer, Ebru (2019)

Proton exchange membrane (PEM) electrolyzers are considered as the most promising candidates for the supply of high purity hydrogen through water electrolysis. As a non polluting technology these electrolyzers enable to store surplus electricity of intermittent renewable power sources. In the highly acidic corrosive media of PEM electrolyzers, noble metal materials and their oxides represent th...

Studies on shape defined Pt-alloy based nanoparticles for the electrochemical reduction of oxygen

Beermann, Vera (2018)

Fuel cells represent an almost ideal technology to provide electricity from sustainable energies. However, to date expensive platinum catalysts are used which do not provide sufficient performances at the cathode side where the oxygen reduction reaction (ORR) takes place. A cost-efficient and active alternative is represented by the group of Pt-Ni alloys. Octahedral shaped Pt-Ni alloy nanoparti...

Palladium-catalyzed hydroxycarbonylation of 1-dodecene in microemulsion systems: does reaction performance care about phase behavior?

Schmidt, Marcel ; Urban, Carolina ; Schmidt, Svenja ; Schomäcker, Reinhard (2018-10-17)

Catalysis, particularly metal-catalyzed reactions in microemulsion systems, offers a sustainable approach for organic reactions in water. However, it is still a challenging task because of the complex role of the nonionic surfactant in such a system and the interaction of the phase behavior and reaction performance. To get a profound knowledge of this role and interaction, a systematic study of...

Comparison of alkane activation over supported and bulk transition metal oxide catalysts and transition metal free carbon nano structures

Kube, Pierre (2018)

Vanadium-based and transition metal-free catalysts have been extensively studied during the last decades in the partial oxidation of ethane and propane due to the high activity and good selectivity. The selectivity to the desired olefin is, however, still too low for industrial application. Improvements require at first an in-depth understanding of the entire reaction network and the relation o...

Grazing incidence X-ray diffraction

Scherzer, Michael (2018)

The interest to study iridium electrocatalysts originates from their use in PEM electrolyzers, which are used to produce hydrogen from water splitting. The need to overcome the exploitation of fossil fuels and to promote the use of sustainable resources makes this a promising alternative. Usage of expensive and rare iridium additionally pushes research to find cost efficient alternatives, proba...

Surface plasmon resonance based sensor for the detection of glycopeptide antibiotics in milk using rationally designed nanoMIPs

Altintas, Zeynep (2017-07-25)

Glycopeptide antibiotics are known as the last resort for the treatment of serious infections caused by Gram-positive bacteria. The use of milk products contaminated with these antibiotic residues leads to allergic reactions and sensitivity in human. Also, long-term consumption of milk products containing low levels of these antibiotics may cause the relevant bacteria to build up resistance to ...

Property-performance correlations in the oxidative coupling of methane

Wang, Huan (2018)

The oxidative coupling of methane is a “dream reaction” in heterogeneous catalysis to achieve direct conversion for natural gas towards value-added and easily transportable C2 products with high economic relevance. Although extensive academic papers and patents have been reported over the last three decades, no economically viable industrial-scale application is yet achieved because of the limi...

Rhodium-catalysed hydroformylation of long-chain alkenes in aqueous multiphase systems: Kinetic studies and systematic process development

Pogrzeba, Tobias (2018)

In the course of the development of new sustainable industrial chemical processes the exploitation of switchable solvent systems is increasingly investigated in various fields. The application of highly efficient catalysts and safer solvents is mandatory to make a step towards a greener chemistry, as well as to find innovative ways to reduce waste from chemical reactions. Consequently, the use ...

High throughput modules for performance and mechanism assessment of flame retardants in polymeric materials

Rabe, Sebastian (2017)

Due to the ever-increasing number of additives, adjuvants, synergists, and fillers, together with variations in concentration, particle size distribution and other modifications, methods for accelerated assessment of flame retarded polymeric materials are strongly needed. This work presents two novel approaches to assess the rapid screening of flame retardants in polymeric materials. Furthermor...