A5040374592- Electrocatalysts for Energy Conversion
- Fuel Cells and Related Materials
- Advanced battery technologies research
- Electrochemical Analysis and Applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Advanced Battery Materials and Technologies
- Advanced Memory and Neural Computing
- Catalysis and Hydrodesulfurization Studies
- Advancements in Battery Materials
- Machine Learning in Materials Science
- Electrohydrodynamics and Fluid Dynamics
- Catalytic Processes in Materials Science
- Extraction and Separation Processes
- Conducting polymers and applications
- Synthesis and characterization of novel inorganic/organometallic compounds
- Inorganic Fluorides and Related Compounds
- Innovative Microfluidic and Catalytic Techniques Innovation
- Supercapacitor Materials and Fabrication
- CO2 Reduction Techniques and Catalysts
- Corrosion Behavior and Inhibition
- Advanced Battery Technologies Research
- Fluorine in Organic Chemistry
- Minerals Flotation and Separation Techniques
- Nanomaterials for catalytic reactions
Technische Universität Berlin
2018-2025
Philipps University of Marburg
2015
We report and study the translation of exceptionally high catalytic oxygen electroreduction activities molybdenum-doped octahedrally shaped PtNi(Mo) nanoparticles from conventional thin-film rotating disk electrode screenings (3.43 ± 0.35 A mgPt–1 at 0.9 VRHE) to membrane assembly (MEA)-based single fuel cell tests with sustained Pt mass 0.45 Vcell, one highest ever reported performances for advanced alloys in real devices. Scanning transmission electron microscopy energy dispersive X-ray...
Cathode catalyst layers of proton exchange membrane fuel cells (PEMFCs) typically consist carbon-supported platinum catalysts with varying weight ratios proton-conducting ionomers. N-Doping carbon support materials is proposed to enhance the performance and durability cathode layer under operating conditions in a PEMFC. However, detailed understanding contributing N-moieties missing. Here, we report successful synthesis cell implementation Pt electrocatalysts supported on N-doped carbons,...
Nitrogen-enriched porous carbons have been discussed as supports for Pt nanoparticle catalysts deployed at cathode layers of polymer electrolyte membrane fuel cells (PEMFC). Here, we present an analysis the chemical process carbon surface modification using ammonolysis preoxidized blacks, and correlate their structure with catalytic activity stability in situ analytical techniques. Upon ammonolysis, support materials were characterized respect to elemental composition, physical area, zeta...
The intermittency of renewable energy is a key limiting factor for the successful decarbonization both producing and consuming sectors. Green hydrogen has potential to act as central vector connecting hard-to-abate sectors power. However, combining storage conversion holistic electrolyzer system remains challenging. Here we show innovative Zink-Zwischenschritt Elektrolyseur (ZZE), or Zinc Intermediate step Electrolyzer in English, that decouples water splitting reaction uses zinc store...
Using a variety of in situ techniques, we tracked the structural stability and concomitantly electrocatalytic oxygen reduction reaction (ORR) platinum nanoparticles on ruthenium–titanium mixed oxide (RTO) supports during electrochemical accelerated stress tests, mimicking fuel cell operating conditions. High-energy X-ray diffraction (HE-XRD) offered insights evolution morphology structure RTO-supported Pt potential cycling. The changes atomic composition were using scanning flow measurements...
The theoretical design of effective metal electrocatalysts for energy conversion and storage devices relies greatly on supposed unilateral effects catalysts structure electrocatalyzed reactions. Here, by using high-energy X-ray diffraction from the new Extremely Brilliant Source European Synchrotron Radiation Facility (ESRF-EBS) device-relevant Pd Pt nanocatalysts during cyclic voltammetry experiments in liquid electrolytes, we reveal near ubiquitous feedback various electrochemical...
Recently proposed bimetallic octahedral Pt-Ni electrocatalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cell (PEMFC) cathodes suffer from particle instabilities form of Ni corrosion and shape degradation. Advanced trimetallic Pt-based have contributed to their catalytic performance stability. In this work, we propose analyse a novel quaternary (oh-)Pt nanoalloy concept with two distinct metals serving as stabilizing surface dopants. An efficient solvothermal...
SEM images reveal the dendritic structure of MCNDs with high surface area, excellent porosity, and uniform distribution leading to outstanding performance Pt catalysts based on making a highly effective supporting material.
Shape-selective, sub-10 nm-sized metal nanoparticles are of high fundamental and practical interest in catalysis electrocatalysis, where the surface structure dictates kinetic properties nanomaterials. Unlike their bimetallic analogues, synthesis size-controlled, pure Pt octahedral nanocatalysts has remained a formidable chemical challenge. In shaped systems, however, benefit shape is often convoluted with composition complex ways. present work, seed-templated approach presented for...
We have carried out a basic study on the charge transfer across interface between LiNi0.5Mn1.5O4 (LNMO) thin-film cathodes and different solid electrolyte coatings, namely LiNbO3, ZrO2 Li4Ti5O12. In contact to LNMO, spinel material Li4Ti5O12 should act as electrolyte, since it exhibits very low electronic conductivity in fully oxidized state. The thin films were prepared by means of sol-gel chemistry spin-coating. electrochemical interfacial properties studied combining impedance...
Abstract So far unknown bis(triarylphosphoranylidene)iminium cations [PPN] + with one fluorine atom in para ([PPN‐1 F ] ), two meta ([PPN‐2 or three and positions of the phenyl rings ([PPN‐3 ) were obtained by a newly developed one‐pot reaction. These halogenated characterized IR Raman spectroscopy comparison quantum‐chemical calculations, ESI mass spectrometry, NMR spectroscopy, single‐crystal X‐ray diffraction. To assess their quality as weakly coordinating associated ability to stabilize...
Identifying the structural response of nanoparticle-support ensembles to reaction conditions is essential determine their structure in catalytically active state as well unravel possible degradation pathways. In this work, we investigate (electronic) carbon- and oxide-supported Pt nanoparticles during electrochemical oxidation by situ X-ray diffraction, absorption spectroscopy dissolution rate mass spectrometry. We prepared ellipsoidal impregnation carbon titanium-based oxide support...
Pt-based nanoparticles supported on carbon materials are state-of-the-art electrocatalysts for proton exchange membrane fuel cells (PEMFCs). Interparticle distance and particle size of the play a crucial role catalyst's performance. The synthesis approach wet impregnation thermal reduction in regular static packed-bed tube furnace often results poorly distributed Pt particles terms interparticle size. Here, we report fluidized bed gas reactor preparation well-dispersed nanoparticles. To...
Proton Exchange Membrane Fuel Cells (PEMFCs) offer energy solutions of high efficiency and low environmental impact. However, the sluggish kinetics oxygen reduction reaction (ORR) at cathode limit...
Metal nitrogen carbon catalysts (MNC) are an attractive substitute for platinum-based in the oxygen reduction reaction (ORR) PEM fuel cells. However, state-of-the-art MNC still suffer from low activity and instability. Li et al. [1] demonstrated use of zinc imidazolate frameworks (ZIF-8) chemical vapor deposition (CVD) to form active sites without unwanted particle formation or additional treatment steps. In this method, gaseous iron chloride exchanges precatalyst sites. work, we introduce a...
The proton exchange membrane fuel cell (PEMFC) is a promising device for the transportation sector of fossil free society, using green hydrogen from water electrolysis as clean and sustainable option. However, sluggish kinetics well durability issues limit implementation until this day. Therefore, modifications to platinum catalysts [1] carbon supports [2] are made improve overall performance cathode catalyst system. Herein, we present investigation corrosion behavior different support...
Pt-based nanoparticles supported on carbon materials are state-of-the-art electrocatalysts for proton exchange membrane fuel cells (PEMFCs). Particle size and interparticle distance of the play a crucial role catalyst's performance. The synthesis approach wet impregnation thermal reduction in regular tube furnace tends to lead inhomogeneous distributed Pt particles terms distance. Therefore, we introducing home-built fluidized bed reactor well-distributed locally separated nanoparticles. In...
The proton exchange membrane fuel cell (PEMFC) has drawn attention as a promising alternative to fossil fuel-based combustion engines. requirements for next-level PEMFC electrocatalysts are severe: high mass activity accompanied by performance stability low loaded Pt-based electrodes. [1] This results in challenging target the catalyst design on cathode site. Further reduction of Pt loading is limited due additional voltage losses originating from O 2 transport resistances. [2] objective...
Abstract The theoretical design of effective metal electrocatalysts for energy conversion and storage devices relies on the structure sensitivity electrochemical processes to their catalyst materials, assuming structural integrity during operation. However, predictions do not necessarily match practical performance. Here, by using high-energy X-ray diffraction from new Extremely Brilliant Source European Radiation Synchrotron Facility (ESRF-EBS) device-relevant Pd Pt nanocatalysts cyclic...