A5053834748- Hydrogen Storage and Materials
- Ammonia Synthesis and Nitrogen Reduction
- MXene and MAX Phase Materials
- nanoparticles nucleation surface interactions
- Graphene research and applications
- Drilling and Well Engineering
- Magnesium Alloys: Properties and Applications
- Hydraulic Fracturing and Reservoir Analysis
- Boron and Carbon Nanomaterials Research
- Catalytic Processes in Materials Science
- Electronic and Structural Properties of Oxides
- Quantum and electron transport phenomena
- Magnetic properties of thin films
- Oil and Gas Production Techniques
- Copper-based nanomaterials and applications
- 2D Materials and Applications
- Internet Traffic Analysis and Secure E-voting
- African Botany and Ecology Studies
- Coagulation and Flocculation Studies
- Reservoir Engineering and Simulation Methods
- Maritime Transport Emissions and Efficiency
- Muon and positron interactions and applications
- Sensor Technology and Measurement Systems
- Gold and Silver Nanoparticles Synthesis and Applications
- Analytical Chemistry and Sensors
Technical University of Denmark
2024-2025
Center for Nanoscale Science and Technology
2025
McMaster University
2022-2024
Centre for Cellular and Molecular Biology
2022
Kerala University of Fisheries and Ocean Studies
2022
ReNorway (Norway)
2020
Trondheim Kommune
2020
Amrita Vishwa Vidyapeetham
2016-2019
Dutch Institute for Fundamental Energy Research
2018
University of Groningen
2010-2017
Nowadays bimetallic nanoparticles (NPs) have emerged as key materials for important modern applications in nanoplasmonics, catalysis, biodiagnostics, and nanomagnetics. Consequently the control of structural motifs with specific shapes provides increasing functionality selectivity related applications. However, producing NPs well controlled still remains a formidable challenge. Hence, we present here general methodology gas phase synthesis distinctively different ranging at single particle...
Mg-Ti alloys have uncommon optical and hydrogen absorbing properties, originating from a ``spinodal-like'' microstructure with small degree of chemical short-range order in the atomic distribution. In present study we artificially engineer by depositing Pd-capped Mg/Ti multilayers different periodicities. Notwithstanding large lattice mismatch between Mg Ti, as-deposited metallic show good structural coherence. On exposure to ${\text{H}}_{2}$ gas two-step hydrogenation process occurs Ti...
Colloidal nanocrystals electronic energy levels are determined by strong size-dependent quantum confinement. Understanding the configuration of nanocrystal superlattices is vital in order to use them heterostructures with other materials. A powerful method reported determine PbS assemblies combining utilization electric-double-layer-gated transistors and advanced ab-initio theory. As a service our authors readers, this journal provides supporting information supplied authors. Such materials...
Using in-situ scanning transmission electron microscopy (STEM) and low-loss plasmon energy-loss spectroscopy (EELS), we reveal asymmetric transformation mechanisms during the hydrogenation dehydrogenation of Mg thin films. Remarkably, hydrogenation, MgH₂ phase can nucleate from either bottom or top interface a film while symmetrically sandwiched between two Ti layers. This unexpected behavior, occurring under identical external conditions, highlights critical role nucleation barriers in...
In this work we present a unique transmission electron microscopy study of the thermal stability gas phase synthesized Mg nanoparticles, which have attracted strong interest as high capacity hydrogen storage materials. Indeed, nanoparticles with MgO shell (∼3 nm thick) annealed at 300 °C show evaporation, void formation, and growth in core both vacuum under pressure environment. This is mainly due to outward diffusion evaporation simultaneously inward vacancies leading (Kirkendall effect)....
Magnesium thin films covered with a layer of Pd absorb hydrogen at much higher pressures than bulk Mg. Such an effect was originally explained as consequence elastic clamping on Mg by the capping layer. An alternative interpretation later suggested that pressure increase could originate from simple alloying between and Pd. Here we resolve this controversy measuring hydrogenation dehydrogenation isotherms Mg-Pd film alloys over wide range compositions. Our results disentangle effects...
A scalable platform to synthesize ultrathin heavy metals may enable high-efficiency charge-to-spin conversion for next-generation spintronics. Here, we report the synthesis of air-stable, epitaxially registered monolayer Pb underneath graphene on SiC (0001) by confinement heteroepitaxy (CHet). Diffraction, spectroscopy, and microscopy reveal that CHet-based intercalation predominantly exhibits a mottled hexagonal superstructure due an ordered network Frenkel-Kontorova-like domain walls. The...
Using in situ scanning transmission electron microscopy (STEM) and low-loss plasmon energy-loss spectroscopy (EELS), we reveal asymmetric transformation mechanisms during the hydrogenation dehydrogenation of Mg thin films. Remarkably, hydrogenation, MgH2 phase can nucleate from either bottom or top interface a film while symmetrically sandwiched between two Ti layers. This unexpected behavior, occurring under identical external conditions, highlights critical role nucleation barriers...
A single step synthesis of hierarchical MgO nanoparticle–nanofiber composite using surfactant driven electrospinning.
Abstract Novel confinement techniques facilitate the formation of non‐layered 2D materials. Here it is demonstrated that and properties oxides (GaO x , InO SnO ) at epitaxial graphene (EG)/silicon carbide (SiC) interface dependent on EG buffer layer prior to element intercalation. Using Ga, defects in lead Ga transforming GaO with non‐periodic oxygen a crystalline matrix via air oxidation room temperature. However, monolayer 2 bilayer O 3 ferroelectric wurtzite structure(FE‐WZ') can then be...
In this work we report strategies to nucleate bimetallic nanoparticles (NPs) made by gas phase synthesis of elements showing difficulty in homogeneous nucleation. It is shown that the nucleation assisted problem NP can be solved via following pathways: (i) selecting an element which itself and act as a center for NPs; (ii) introducing H2 or CH4 impurity/trace initiate during NPs. The latter solve if none We illustrate abovementioned case Mg based NPs, are interesting hydrogen storage...
Here we report the extraordinary thermal stability of Mg rich bimetallic nanoparticles (NPs), which is important for hydrogen storage.
Although copper nanoparticles are used as model nanomaterial because of their small nucleation barrier, oxidization sensitivity hampers production fully metallic with controlled size and shape. Nevertheless, we demonstrate here synthesis nanoparticles, via high pressure magnetron sputtering, having highly tunable sizes shapes over a range spanning two orders magnitude. This is achieved by exploiting reducing gas environment to mediate proper conditions, allowing control robust motifs for...
Electrochemical deuteration of metastable Mg-Ti alloys is studied. To investigate the dynamics deuterium atoms in crystal host, as-prepared hydrides are examined by means NMR spectroscopy. Remarkably host compound, which phase segregates upon gas at high temperatures, preserves its original structure during low temperature electrochemical deuteration. Deuterium exchange dynamically between Mg-rich and Ti-rich sites. As a service to our authors readers, this journal provides supporting...
The effect of titanium on magnesium nanoparticle formation is investigated in relation to the importance Mg hydrogen storage. Addition Ti reduces Mg-nanoparticle sizes range 5–20 nm and leads less protective Mg-oxide shells. This return accelerates evaporation that hollow cores. presence oxygen plays a dual role forming MgO protected stable nanoparticles above critical size (∼15 nm) ones below this both due oxidation associated Kirkendall effects.
We report a catalyst free and substrate independent synthesis of magnesium nanowires using simple thermal evaporation method.
This work focuses on improving the thermal stability of Mg nanoparticles (NPs) for use in hydrogen storage. Three ways are investigated that can achieve this goal. (i) Addition Cu prevents void formation during NP production and reduces fast evaporation/voiding annealing. (ii) Alloying prevent evaporation: e.g., with Ni forms a thermally stable core/shell (MgNi2/Ni) preventing evaporation (iii) Covering NPs Ti film leads to suppression vacuum Indeed, hydrogenation Ti/Mg shows γ-MgH2 phase as...
Abstract As the oilfield industry requires new techniques to generate diversion over large pay zones and easier methods perform workover operations interventions through Coiled Tubing, research is focused provide with technologies that support growing demand for oil gas in world. Fluid systems are used divert acid non-mechanical isolation on a wellbore have traditionally been viscosified fluids solid particulates. These substances create (in most cases) drastic permeability reduction near...
Gas-phase tuning of different structural motifs and shape MgTi bimetallic nanoparticles using H<sub>2</sub> CH<sub>4</sub> as trace gas impurities.
Over the past few years there are many developments in area of classification data mining. Classification is a supervised learning method, that maps into predefined groups or classes. Nowadays techniques extensively used different applications. In this most research works done on text, image, signal etc. The main goal paper to use dictionary-based approach learn, represent and classify documents. We consider dictionary as collection documents each document represented vectors. An algorithm...
The schematic representation shows the synthesis of different Mg nanostructures using thermal evaporation method.
High temperature annealing of gas phase synthesized Mg nanoparticles surrounded by an MgO shell leads to formation hollow nanoshells due the evaporation assisted Kirkendall effect. Under electron beam exposure in TEM, (220) facets reduce their high surface energy forming cube facets, which is followed nanoshell size reduction and collapse within a few minutes. However, ambient conditions remain stable for significant periods time further degrade becoming filled with carbon while lossing any...