Markus Heidelmann
YOU?
Author Swipe
View article: Mechanistic Understanding of Laser‐Induced Defect Engineering of Anisotropic Cobalt Oxide Spinel Platelets in Water
Mechanistic Understanding of Laser‐Induced Defect Engineering of Anisotropic Cobalt Oxide Spinel Platelets in Water Open
In this study, we employ the pulsed laser defect engineering in liquid (PUDEL) to tailor the surface properties of cobalt (II, III) oxide (Co 3 O 4 ) platelets grown in the < 111 > direction. By varying the laser intensity and pulse number…
View article: Insight into the Correlation of Shape and Magnetism of Hematite Nanospindles
Insight into the Correlation of Shape and Magnetism of Hematite Nanospindles Open
It is established that the Morin transition, a spin reorientation in hematite, is shifted to lower temperatures with decreasing nanoparticle volume. However, our findings indicate an opposite effect in a series of hematite nanospindles: Th…
View article: Unveiling Surface Species Formed on Ni‐Fe Spinel Oxides During the Oxygen Evolution Reaction at the Atomic Scale
Unveiling Surface Species Formed on Ni‐Fe Spinel Oxides During the Oxygen Evolution Reaction at the Atomic Scale Open
Optimizing electrocatalyst performance requires an atomic‐scale understanding of surface state changes and how those changes affect activity and stability during the reaction. This is particularly important for the oxygen evolution reactio…
View article: Scanning Transmission Electron Microscopy Analysis of the Si(111)–AlN–GaN Nanowire Interface Grown by Polarity‐ and Site‐Controlled Growth Method
Scanning Transmission Electron Microscopy Analysis of the Si(111)–AlN–GaN Nanowire Interface Grown by Polarity‐ and Site‐Controlled Growth Method Open
In GaN‐on‐Si nanowire integration schemes, where the nanowires are contacted through the substrate, the interfaces between silicon substrate, AlN buffer layer, and GaN nanowire are of high interest. Herein, analysis by scanning transmissio…
View article: Poly(4‐Vinylpyridine)‐Based Cubosomes: Synthesis, Assembly, and Loading Capabilities
Poly(4‐Vinylpyridine)‐Based Cubosomes: Synthesis, Assembly, and Loading Capabilities Open
Polymer cubosomes (PCs) are 3D porous microparticles with high surface area that have great potential for applications that require a large interfacial area including catalysis, drug delivery, and energy storage. Most reported PCs are base…
View article: Effects of Dynamic Surface Transformation on the Activity and Stability of Mixed Co‐Mn Cubic Spinel Oxides in the Oxygen Evolution Reaction in Alkaline Media
Effects of Dynamic Surface Transformation on the Activity and Stability of Mixed Co‐Mn Cubic Spinel Oxides in the Oxygen Evolution Reaction in Alkaline Media Open
An atomic‐scale understanding of how electrocatalyst surfaces reconstruct and transform during electrocatalytic reactions is essential for optimizing their activity and longevity. This is particularly important for the oxygen evolution rea…
View article: Correlating atomic-scale structural and compositional details of Ca-doped LaCoO3 perovskite nanoparticles with activity and stability towards the oxygen evolution reaction
Correlating atomic-scale structural and compositional details of Ca-doped LaCoO3 perovskite nanoparticles with activity and stability towards the oxygen evolution reaction Open
Developing efficient oxygen evolution reaction (OER) electrocatalysts requires a thorough understanding of structure–activity-stability relationships, ideally at the atomic scale. Herein, we employed atom probe tomography and transmission …
View article: Kinetics of Direct Reaction of Vanadate, Chromate, and Permanganate with Graphene Nanoplatelets for Use in Water Purification
Kinetics of Direct Reaction of Vanadate, Chromate, and Permanganate with Graphene Nanoplatelets for Use in Water Purification Open
Oxometalates of vanadium(V), chromium(VI), and manganese(VII) have negative impacts on water resources due to their toxicity. To remove them, the kinetics of 0.04 mM oxometalates in natural and synthetic water were studied using graphene n…
View article: Tunable Syngas Formation at Industrially Relevant Current Densities via CO<sub>2</sub>Electroreduction and Hydrogen Evolution over Ni and Fe‐derived Catalysts obtained via One‐Step Pyrolysis of Polybenzoxazine Based Composites
Tunable Syngas Formation at Industrially Relevant Current Densities via CO<sub>2</sub>Electroreduction and Hydrogen Evolution over Ni and Fe‐derived Catalysts obtained via One‐Step Pyrolysis of Polybenzoxazine Based Composites Open
Simultaneous electroreduction of CO 2 and H 2 O to syngas can provide a sustainable feed for established processes used to synthesize carbon‐based chemicals. The synthesis of MO x /M‐N‐Cs (M = Ni, Fe) electrocatalysts reported via one‐step…
View article: Correlating Atomic-Scale Structural and Compositional Details of Perovskites with Activity and Stability Towards the Oxygen Evolution Reaction
Correlating Atomic-Scale Structural and Compositional Details of Perovskites with Activity and Stability Towards the Oxygen Evolution Reaction Open
View article: Graphene self-folding: Evolution of free-standing few-layer graphene in plasma synthesis
Graphene self-folding: Evolution of free-standing few-layer graphene in plasma synthesis Open
Substrate and catalyst free gas-phase plasma synthesis of freestanding few-layer graphene (FLG) flakes leads to crumpled FLG structures. In this paper, we elucidate a folding-based mechanism and structure-formation process in accordance wi…
View article: Machine Hammer Peening and Its Effect on the Surface Integrity of Arc-Sprayed WC-W2C-FeCMnSi Coatings
Machine Hammer Peening and Its Effect on the Surface Integrity of Arc-Sprayed WC-W2C-FeCMnSi Coatings Open
With respect to post-processing techniques in the field of surface engineering, it was recently found that machine hammer peening (MHP) represents a promising approach to functionalizing thermally sprayed coatings as the MHP contributes to…
View article: Multicompartment Nanostructures as Templates for Multimetallic Hybrid Materials
Multicompartment Nanostructures as Templates for Multimetallic Hybrid Materials Open
ABC triblock terpolymers are promising soft templates for organic/inorganic hybrids because of their ability to form nanostructures with complex shapes, multiple compartments, and precisely localized chemistry. Exemplified on multicompartm…
View article: Linking Composition, Structure and Thickness of CoOOH layers to Oxygen Evolution Reaction Activity by Correlative Microscopy
Linking Composition, Structure and Thickness of CoOOH layers to Oxygen Evolution Reaction Activity by Correlative Microscopy Open
The role of β‐CoOOH crystallographic orientations in catalytic activity for the oxygen evolution reaction (OER) remains elusive. We combine correlative electron backscatter diffraction/scanning electrochemical cell microscopy with X‐ray ph…
View article: Linking Composition, Structure and Thickness of CoOOH layers to Oxygen Evolution Reaction Activity by Correlative Microscopy
Linking Composition, Structure and Thickness of CoOOH layers to Oxygen Evolution Reaction Activity by Correlative Microscopy Open
The role of β‐CoOOH crystallographic orientations in catalytic activity for the oxygen evolution reaction (OER) remains elusive. We combine correlative electron backscatter diffraction/scanning electrochemical cell microscopy with X‐ray ph…
View article: Cobalt nickel boride as electrocatalyst for the oxidation of alcohols in alkaline media
Cobalt nickel boride as electrocatalyst for the oxidation of alcohols in alkaline media Open
A mixed Co and Ni boride precursor was synthesized via chemical reduction and subsequently annealed at 400 or 500 °C with or without prior addition of the monomer benzoxazine (BO). The resulting mixed CoNiB materials were investigated as e…
View article: Differentiating between Acidic and Basic Surface Hydroxyls on Metal Oxides by Fluoride Substitution: A Case Study on Blue TiO<sub>2</sub> from Laser Defect Engineering
Differentiating between Acidic and Basic Surface Hydroxyls on Metal Oxides by Fluoride Substitution: A Case Study on Blue TiO<sub>2</sub> from Laser Defect Engineering Open
Both oxygen vacancies and surface hydroxyls play a crucial role in catalysis. Yet, their relationship is not often explored. Herein, we prepare two series of TiO 2 (rutile and P25) with increasing oxygen deficiency and Ti 3+ concentration …
View article: Unterscheidung zwischen sauren und basischen Oberflächenhydroxylgruppen auf Metalloxiden durch Fluoridsubstitution: Eine Fallstudie am Beispiel von defektreichem, blauem TiO<sub>2</sub> aus der laserbasierten Defekterzeugung
Unterscheidung zwischen sauren und basischen Oberflächenhydroxylgruppen auf Metalloxiden durch Fluoridsubstitution: Eine Fallstudie am Beispiel von defektreichem, blauem TiO<sub>2</sub> aus der laserbasierten Defekterzeugung Open
Sowohl oberflächennahe Sauerstofffehlstellen als auch Hydroxylgruppen an der Oberfläche spielen eine entscheidende Rolle in der Katalyse. Dennoch bleiben die genauen Zusammenhänge durch die limitierte analytische Zugänglichkeit dieser Stru…
View article: Graphene Origami: Evolution of Free-Standing Few-Layer Graphene in Plasma Synthesis
Graphene Origami: Evolution of Free-Standing Few-Layer Graphene in Plasma Synthesis Open
View article: Correction: Comparison of EUV Photomask Metrology Between CD-AFM and TEM
Correction: Comparison of EUV Photomask Metrology Between CD-AFM and TEM Open
View article: Beneficial Effects of Low Iron Contents on Cobalt‐Containing Spinel Catalysts in the Gas Phase 2‐Propanol Oxidation
Beneficial Effects of Low Iron Contents on Cobalt‐Containing Spinel Catalysts in the Gas Phase 2‐Propanol Oxidation Open
Oxidation reactions are highly relevant transformation reactions in the industry. Mixed Co and Fe containing oxides are promising substituents for noble‐metal‐based catalysts due to lower cost and higher thermal stability. Performing oxida…
View article: Comparison of EUV Photomask Metrology Between CD-AFM and TEM
Comparison of EUV Photomask Metrology Between CD-AFM and TEM Open
Accurate metrology of extreme ultraviolet (EUV) photomask is a crucial task. In this paper, two different methods for reference EUV photomask metrology are compared. One is the critical dimension atomic force microscopy (CD-AFM). In the me…
View article: 3D atomic-scale imaging of mixed Co-Fe spinel oxide nanoparticles during oxygen evolution reaction
3D atomic-scale imaging of mixed Co-Fe spinel oxide nanoparticles during oxygen evolution reaction Open
The three-dimensional (3D) distribution of individual atoms on the surface of catalyst nanoparticles plays a vital role in their activity and stability. Optimising the performance of electrocatalysts requires atomic-scale information, but …
View article: The Effect of Water on the 2‐Propanol Oxidation Activity of Co‐Substituted LaFe<sub>1−x</sub>Co<sub>x</sub>O<sub>3</sub> Perovskites
The Effect of Water on the 2‐Propanol Oxidation Activity of Co‐Substituted LaFe<sub>1−x</sub>Co<sub>x</sub>O<sub>3</sub> Perovskites Open
Perovskites are interesting oxidation catalysts due to their chemical flexibility enabling the tuning of several properties. In this work, we synthesized LaFe 1−x Co x O 3 catalysts by co‐precipitation and thermal decomposition, characteri…
View article: The ultramicrotome as a tool for the preparation of ultra- thin samples for TEM investigations
The ultramicrotome as a tool for the preparation of ultra- thin samples for TEM investigations Open
View article: Influence of Nanoparticle Processing on the Thermoelectric Properties of (Bi<sub>x</sub>Sb<sub>1−X</sub>)<sub>2</sub>Te<sub>3</sub> Ternary Alloys
Influence of Nanoparticle Processing on the Thermoelectric Properties of (Bi<sub>x</sub>Sb<sub>1−X</sub>)<sub>2</sub>Te<sub>3</sub> Ternary Alloys Open
The synthesis of phase‐pure ternary solutions of tetradymite‐type materials (Bi x Sb 1−x ) 2 Te 3 (x=0.25; 0.50; 0.75) in an ionic liquid approach has been carried out. The nanoparticles are characterized by means of energy‐dispersive X‐ra…
View article: Room temperature synthesized solid solution AuFe nanoparticles and their transformation into Au/Fe Janus nanocrystals
Room temperature synthesized solid solution AuFe nanoparticles and their transformation into Au/Fe Janus nanocrystals Open
Solid solution AuFe nanoparticles with paramagnetic Fe atoms in the Au matrix synthesized at 25 °C transform into Janus particles upon annealing at 700 °C with the ferromagnetic bcc Fe phase epitaxially grown on fcc Au.
View article: Ameisensäure‐unterstützte selektive Hydrogenolyse von 5‐Hydroxymethylfurfural zu 2,5‐Dimethylfuran über bifunktionale Pd‐Nanopartikel auf N‐dotiertem mesoporösem Kohlenstoff als Träger
Ameisensäure‐unterstützte selektive Hydrogenolyse von 5‐Hydroxymethylfurfural zu 2,5‐Dimethylfuran über bifunktionale Pd‐Nanopartikel auf N‐dotiertem mesoporösem Kohlenstoff als Träger Open
Aus Biomasse gewonnenes 5‐Hydroxymethylfurfural (HMF) gilt als vielversprechende Plattformchemikalien zur Herstellung von 2,5‐Dimethylfuran (DMF) als flüssigen Transportkraftstoff. Pd‐Nanopartikel auf N‐haltigen und N‐freien mesoporösen Ko…
View article: Formic Acid‐Assisted Selective Hydrogenolysis of 5‐Hydroxymethylfurfural to 2,5‐Dimethylfuran over Bifunctional Pd Nanoparticles Supported on N‐Doped Mesoporous Carbon
Formic Acid‐Assisted Selective Hydrogenolysis of 5‐Hydroxymethylfurfural to 2,5‐Dimethylfuran over Bifunctional Pd Nanoparticles Supported on N‐Doped Mesoporous Carbon Open
Biomass‐derived 5‐hydroxymethylfurfural (HMF) is regarded as one of the most promising platform chemicals to produce 2,5‐dimethylfuran (DMF) as a potential liquid transportation fuel. Pd nanoparticles supported on N‐containing and N‐free m…
View article: High-Angle Annular Dark-Field (HAADF) Contrast
High-Angle Annular Dark-Field (HAADF) Contrast Open