img-paralax2-1024x533

Nanostructured Materials

RESEARCH

DEPARTMENTS
aemicros.png
RESEARCH GROUPS
Atomic
Nanostructured_Rale

DESCRIPTION

Our research group in the Department of Advanced Electron Microscopy, Imaging and Spectroscopy (AEMIS) at INL is involved in understanding the atomic structure of materials (energy related and catalytically important materials) and correlating it with their properties using a combination of electron microscopic and spectroscopic tools. Understanding the structure of materials is fundamental to exploring their various interesting properties: magnetic, optical and optoelectronic. The studies are carried out by employing the state-of-the art aberration corrected S/TEM in combination with analytical electron microscopy to provide combined atomic structure – chemical sensitive information.

RESEARCH PROJECTS

The hollow interior core of nanotubes, both carbon and non-carbon (BN, WS2 etc.) provide the necessary space for the filling, encapsulation and confinement of molecules and crystals both organic and inorganic. In addition they provide templates for the formation of core-shell nanotubes. The reduced dimensionality of the encapsulated material as a consequence of “confinement” presents the advantage of different characteristics compared to that of the bulk material. The interaction between the encapsulated material and the host nanotube plays a crucial role and therefore can govern the structure and electronic properties of such a system.
In this project nanotubes (CNTs as well as Inorganic NTs) which provide accessible space for templated growth of nanotubes or nanorods within them are employed to encapsulate metal halides such as GdI3 and BiI3 which are contrast agents for biomedical imaging. Capillary filling is employed to encapsulate these metal halides within nanotubes of carbon and WS2 to obtain core-shell nanotubes and/or nanorods. Aberration Corrected Scanning/Transmission Electron Microscopy and Spectroscopy using Titan G2 80-200 TEM/STEM with ChemiSTEM Technology and FEI Titan Themis 60-300 kV is employed to characterize the atomic structure, morphology and composition of these core-shell structures.

Project2_picture

External Collaborations:
Dr. Pedro Costa and Nitin M. Batra (KAUST, Saudi Arabia)

Dr. Andrey Enyashin – Molecular Dynamics Simulation (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Publications
(1) Nitin M. Batra, E. A. Anumol, Jasmin Smajic, Andrey N. Enyashin, Francis Leonard Deepak and Pedro M. F. J. Costa, Morphological phase diagram of a metal halide encapsulated in carbon nanotubes, Submitted (2017).
(2) Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes, E. A. Anumol, A. N. Enyashin, N. M. Batra, P. M. F. J. Costa and Francis Leonard Deepak, Nanoscale, 2016, 8, 12170-12181.
(3) Capillary Imbibition of Gadolinium Halides into WS2 Nanotubes: A Molecular Dynamics View, Francis Leonard Deepak and A. N. Enyashin, Isr. J. Chem, 2017, Special Issue: Computational Science of Inorganic Nanostructures, 2017, 57, 501-508. doi:10.1002/ijch.201600055.

People in this Project: E.A. Anumol and Francis Leonard Deepak

In this project HAADF-STEM tomography is employed to obtain the 3D morphology of nanomaterials such as nanocatalysts and core-shell nanotubes. A Titan G2 80-200 TEM/STEM with ChemiSTEM Technology is used for this. EDX-STEM tomography is employed to obtain 3D chemical mapping. Low accelerating voltage (80 kV) enables tomography of beam sensitive materials such as carbon nanotubes. A high tilt tomography holder  and Super-X EDS detector (in the Titan ChemiSTEM) comprising four SDD detectors enable the EDX mapping in a wide tilt range (-70° to +70°) . Inspect 3D software is used for reconstruction and Amira for visualization.

Volume rendering of HAADF-STEM and EDS tomograms of GdI3@WS2 nanotube. (a) Nanotube positioned vertically. From left to right, HAADF-STEM tomogram, combined tomograms of each element and individual elemental tomograms are given. (b) Cross-sectional view of the nanotube. The elements are color coded as blue (W), green (S), yellow (Gd) and red (I).

Volume rendering of HAADF-STEM and EDS tomograms of GdI3@WS2 nanotube. (a) Nanotube positioned vertically. From left to right, HAADF-STEM tomogram, combined tomograms of each element and individual elemental tomograms are given. (b) Cross-sectional view of the nanotube. The elements are color coded as blue (W), green (S), yellow (Gd) and red (I).

 External Collaborations:

Dr. Pedro Costa and Mr. Nitin M. Batra (KAUST, Saudi Arabia)

Dr. Andrey Enyashin – Molecular Dynamics Simulation (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Publications

Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes, E. A. Anumol, A. N. Enyashin, N. M. Batra, P. M. F. J. Costa and Francis Leonard Deepak, Nanoscale, 2016, 8, 12170-12181.

People in this Project: Junjie Li and Francis Leonard Deepak

Uncovering atomic scale dynamical processes of lattice induced epitaxial growth of nanocrystal on the support is critical to understanding crystallization, solid-phase epitaxial growth, and advanced nanofabrication, all of which are linked to different important applications in material field.

HRTEM images taken under an electron dose of 2390 e/Å2sec revealing lattice induced interfacial Bi nucleation on SrBiTa2O9 substrate from stable nanocluster and structural fluctuations of the newly formed nanocrystal

HRTEM images taken under an electron dose of 2390 e/Å2sec revealing lattice induced interfacial Bi nucleation on SrBiTa2O9 substrate from stable nanocluster and structural fluctuations of the newly formed nanocrystal

External Collaborations:

Dr. Andrey Enyashin (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Dr. Qiang Li (School of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China).

Dr. Zhongchang Wang (Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan).

Publications

  • In Situ Atomic-Scale Observation of Droplet Coalescence Driven Nucleation and Growth at Liquid/Solid Interfaces, Junjie Li, Qiang Li, Zhongchang Wang, and Francis Leonard Deepak, ACS Nano, 2017, 11 (6), pp 5590–5597.
  • Real-Time Dynamical Observation of Lattice Induced Nucleation and Growth in Interfacial Solid-Solid Phase Transitions, Junjie Li, Qiang Li, Zhongchang Wang, and Francis Leonard Deepak, Growth Des., 2016, 16, 7256−7262.

People in this Project: Junjie Li and Francis Leonard Deepak

 

Doping is an effective method to tune the electronic properties for MoS2 as well as other 2D semiconductors and has significant implications on their optical and electronic properties. In this project we fabricate doped MoS2 samples with different dopants and/or doping concentrations and study them employing high resolution imaging and spectroscopy.

External Collaborations:

Dr. G. Deokar (University of Namur, Belgium)

Publications

  • Geetanjali Deokar, Junjie Li, Francis Leonard Deepak, MoS2 nanoflowers, manuscript in prep.

People in this Project: Markus Snellman, E.A. Anumol, Junjie Li and Francis Leonard Deepak

 

Monometallic, Bimetallic and multimetallic core-shell nanoparticle/nanowire catalysts of noble metal alloys possesses superior activity, high selectivity and stability at low temperature compared to traditional bulk metals. This makes them ideal candidates for carrying out investigations on their structure, nature of alloy formation and thus understand the way the catalytic activity is enhanced. Bimetallic nanoparticles have two fundamental structures: a) alloys and b) core shell structures. There are several routes to the preparation of alloy nanoparticles both bimetallic and core-shell. Factors that will play a role in determining which of the two alternatives is more likely to occur include: the solubility of the metals, the relative surface energy, the kinetics of the synthesis and several others. Direct microscopic studies of various bimetallic nanoparticles have been carried out using high-resolution transmission electron microscopy (HRTEM). However, this method is limited because of the small difference in the lattice constant involved. Conventional transmission electron microscopy (CTEM) can produce chemical contrast due to due to different electron beam extinction distances. This has been applied successfully to image bimetallic nanoparticles down to 10 nm in diameter. Since the particles need to be in a low index zone orientation, this method is not easy to use in practice. As an alternative method of nanostructure determination high angle angular dark field (HAADF) imaging technique has been used successfully. The HAADF method has been used to detect variation in chemical composition down to single atom level in structures of nanosized particles. STEM-HAADF imaging carried out in an aberration corrected microscope reveals the atomistic structure and the alloying of bimetallic nanoparticles and nanowires. In combination with high resolution spectral and chemical analysis this techniques provides unprecedented information never obtained till date. Understanding the nature and structure of such bimetallic/multimetallic nanocatalysts is important to enable modification of their structure/morphology/composition and enhance their catalytic performance for fuel cells and other industrial applications.

HAADF images of a pair of Au-Ag Nanocages and their corresponding STEM-EDS

HAADF images of a pair of Au-Ag Nanocages and their corresponding STEM-EDS

External Collaborations:

Prof. M. Arturo López-Quintela (Dept. Physical Chemistry, Faculty of Chemistry Lab of Nanotechnology and Magnetism (NANOMAG) Research Technological Institute University of Santiago de Compostela)

Dr. P. John Thomas (School of Chemistry, Bangor University, Bangor, UK)

Prof. Maurizio Muniz-Miranda (“Ugo Schiff” Chemistry Dept, University of Florence)

Dr. Roberto Pilot (Consorzio INSTM and Department of Chemical Sciences, via Marzolo 1, 35131 Padova, Italy)

Dr. C.P. Vinod (Catalysis Division and Center of Excellence on Surface Science, CSIR National Chemical Laboratory, Pune, INDIA)

Dr. R. Nandini Devi (Catalysis Division, National Chemical Laboratory, Pune, India)

Publications

  • Magnetic Nanoparticles obtained by two-step Laser Ablation of Nickel and Silver in pure Water, Cristina Gellini, Francis Leonard Deepak, Maurizio Muniz-Miranda, Stefano Caporali, Francesco Muniz-Miranda, Alfonso Pedone, Claudia Innocenti, Claudio Sangregorio, Phys. Chem. C 2017, 121, 3597-3606.
  • A convenient route for Au@Ti-SiO2 nanocatalyst synthesis and its application for room temperature CO oxidation, Yogita Sonia, A. Anumol, Chandrani Nayak, Francis Leonard Deepak, C.P. Vinod, J. Phys. Chem. C 2017, 129, 4946-4957.
  • Understanding alloy structure and composition in sinter-resistant AgPd@SiO2 encapsulated catalysts and their effect on catalytic properties, Sourik Mondal, Thattarathody Rajesh, Basab B Dhar, Markus Snellman, Junjie Li, Francis Leonard Deepak, R. Nandini Devi, Submitted
  • Controlling Bimetallic Nanostructures by the Microemulsion Method with Subnanometer Resolution Using a Prediction Model, David Buceta, Concha Tojo, Miomir Vukmirovic, Francis Leonard Deepak, Arturo M. Lopez-Quintela, Langmuir, 2015, 31, 7435-7439.
  • Wavelength dispersion of the local field intensity in silver–gold nanocages, R. Pilot, Zoppi, S. Trigari, F. L. Deepak, E. Giorgetti and R. Bozio, Phys. Chem. Chem. Phys., 2015, 17, 7355.
  • Stable Ruthenium colloids by Laser Ablation, Brandi, S. Caporali, S. Cicchi, L. Lascialfari, M. Muniz-Miranda, S. Orazzini, M. Severi, Francis Leonard Deepak and E. Giorgetti, IEEE NANO, July 2015.
  • Advanced Methods of Electron Microscopy in Catalysis Research, Miguel Jose-Yacaman, Arturo Ponce-Pedraza, Sergio Mejía-Rosales and Francis Leonard Deepak, Advances in Imaging & Electron Physics (Academic Press), Editor: Peter Hawkes, vol. 177, pp: 279-342 (2013).

People in this Project: Sharath Kumar and Francis Leonard Deepak

The crystal structure of sodium titanate; the black framed area shows the unit cell of the structure.

The crystal structure of sodium titanate; the black framed area shows the unit cell of the structure.

 

The study is aimed at employing electron microcopy in combination with spectroscopic techniques to study these materials and provide an accurate and in-depth understanding into the various aspects related to their catalytic activity. The samples under consideration are transition metal modified TNTs which are prepared by cation exchange of the hydrothermally synthesized TNTs as well as doped TNTs. The techniques include employing Aberration Corrected Electron Microscopy (AC-TEM/STEM) along with the associated spectroscopic techniques, Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-Ray Spectroscopy (EDX), as this could provide the structure, composition and morphology of the specimen in a single experiment, from the same region, with high spatial resolution. Of particular importance would be the identification of the cations that are incorporated as dopants (and/or intercalated) and imaging them with single-atom sensitivity, along with elucidation of their oxidation/bonding states of undoped and doped samples (Ti4+ vs Co2+). It is expected that such a detailed experimental study using electron microscopy would provide new insights into the structural and compositional aspects which influences the catalytic properties.

External Collaborations:

Dr. Anabela Rolo (Dept. Physics, U. Minho, Braga, Portugal)

 

 

Ongoing National/European Projects

 

  • Regulatory testing of nanomaterials (NANoREG), FP7 Nanotechnologies & Nanosciences Thematic Cooperation Programme, Participant, Total funding: 242,000.00 €.
  • WATERNANOENV (National Project), Axencia Galega de Innovación (GAIN)-ERDF Partners: Instituto Tecnológico de Galicia (ITG)-coordinator, Universidade de Santiago de Compostela (USC)-subcontracted and INL-subcontracted, INL budget: €395,000.
  • FCT-Algeria.
  • NORTE 2020 through the European Regional Development Fund (ERDF).

National and International Collaborations

 

  • U. Minho, CICECO – U. Aveiro and INESC-MN (Portugal), USC (Spain), University of Florence (Italy), KAUST (Saudi Arabia), University of Bangor (U.K), NCL Pune (India), Ural Federal University (Russian Federation), University of Austin (USA).

PUBLICATIONS

2017

Nitin M. Batra E. A. Anumol, Jasmin Smajic Andrey Enyashin Francis Leonard Deepak; Costa, Pedro

Morphological phase diagram of a metal halide encapsulated in carbon nanotubes (Journal Article)

Submitted, 2017.

(BibTeX)

Yogita Sonia E.A. Anumol, Chandrani Nayak Francis Leonard Deepak Vinod Phys

A convenient route for Au@Ti-SiO2 nanocatalyst synthesis and its application for room temperature CO oxidation (Journal Article)

Chem. C , 129 (4946-4957), 2017.

(BibTeX)

Sourik Mondal Thattarathody Rajesh, Basab Dhar Markus Snellman Junjie Li Francis Leonard Deepak Nandini Devi

Understanding alloy structure and composition in sinter-resistant AgPd@SiO2 encapsulated catalysts and their effect on catalytic properties (Journal Article)

Submitted , 2017.

(BibTeX)

Cristina Gellini Francis Leonard Deepak, Maurizio Muniz Miranda Stefano Caporali Francesco Muniz-Miranda Alfonso Pedone Claudia Innocenti; Claudio Sangregorio, Phys

Magneto-Plasmonic Colloidal Nanoparticles Obtained by Laser Ablation of Nickel and Silver Targets in Water (Journal Article)

Chem. C, (121), pp. 3597−3606, 2017.

(BibTeX)

Junjie Li Zhongchang Wang, Francis Leonard Deepak

In-situ Atomic-scale Observation of Droplets Coalescence Driven Nucleation and Growth at Liquid/Solid Interface (Journal Article)

Submitted, 2017.

(BibTeX)

2016

E. A. Anumol A. N. Enyashin, Batra Costa; Deepak, Francis Leonard

Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes (Journal Article)

Nanoscale, (8), pp. 12170-12181, 2016.

(BibTeX)

Deepak, Francis Leonard; Enyashin,

Capillary Imbibition of Gadolinium Halides into WS2 Nanotubes: A Molecular Dynamics View (Journal Article)

Isr. J. Chem., 2016.

(Links | BibTeX)

Junjie Li Qiang Li, Zhongchang Wang; Deepak, Francis Leonard

Real-Time Dynamical Observation of Lattice Induced Nucleation and Growth in Interfacial Solid-Solid Phase Transitions (Journal Article)

Cryst. Growth Des., Just Accepted Manuscript, 2016.

(Links | BibTeX)

J. Rodrigo Magana Yury V. Kolen’ko, Francis Leonard Deepak Conxita Solans Rekha Goswami Shrestha Jonathan Hill Katsuhiko Ariga Lok Kumar Shrestha; Rodriguez-Abreu, Carlos

From Chromonic Self-Assembly to Hollow Carbon Nanofibers for Efficient Materials in Supercapacitor and Vapor Sensing Applications (Journal Article)

ACS Applied Materials & Interfaces, 2016.

(Links | BibTeX)

2015

Francis Leonard Deepak Manuel Bañobre-López, Enrique Carbó-Argibay Fátima Cerqueira Yolanda Piñeiro-Redondo JoséRivas Corey Thompson Saeed Kamali Carlos Rodríguez-Abreu Kirill Kovnir; Kolenko, Yury

A Systematic Study of the Structural and Magnetic Properties of Mn‑, Co‑, and Ni-Doped Colloidal Magnetite Nanoparticles (Journal Article)

J. Phys. Chem C, (119), pp. 11947-11957, 2015.

(BibTeX)

David Buceta Concha Tojo, Miomir Vukmirovic Francis Leonard Deepak Arturo Lopez-Quintela

Controlling Bimetallic Nanostructures by the Microemulsion Method with Subnanometer Resolution Using a Prediction Model (Journal Article)

Langmuir, (31), pp. 7435-7439, 2015.

(BibTeX)

Eunice Cunha M. Fernanda Proença, Florinda Costa António Fernandes Marta Ferro Paulo Lopes Mariam Debs Manuel Melle-Franco Francis Leonard Deepak Maria Paiva

Self-assembled functionalized graphene nanoribbons from carbon nanotubes (Journal Article)

ChemistryOpen, (4), pp. 115 – 119, 2015.

(BibTeX)

Maryam Salimian Maxim Ivanov, Francis Leonard Deepak Dmitri Petrovykh Igor Bdikin Marta Ferro Andre Kholkin Elby Titus; Goncalves, Gil

Synthesis and characterization of reduced graphene oxide /spiky nickel nanocomposites for nanoelectronic applications (Journal Article)

J. Mater. Chem. C, (3), pp. 11516 – 11523, 2015.

(BibTeX)

R. Pilot A. Zoppi, Trigari Deepak Giorgettib; Bozioa,

Wavelength dispersion of the local field intensity in silver–gold nanocages (Journal Article)

Phys.Chem.Chem.Phys., (17), pp. 7355, 2015.

(BibTeX)

Nitin M Batra Shashikant P Patole, Ahmed Abdelkader Dalaver Anjum Francis Deepak; Costa, Pedro

Structural changes of electron and ion beam-deposited contacts in annealed carbon-based electrical devices (Journal Article)

Nanotechnology, (26), pp. 445301, 2015.

(BibTeX)

J. D. Costa S. Serrano-Guisan, Borme Deepak Tarequzzaman Paz J.Ventura Ferreira; Freitas,

Impact of MgO thickness on the performance of Spin Transfer Torque Nano-Oscillators​ (Journal Article)

IEEE Trans. Magn, (52), pp. 1401604, 2015.

(BibTeX)

2014

Francis Leonard Deepak Jose Rivas, Miguel Jose-Yacaman

Understanding the structure of nanocatalysts with High Resolution Scanning/ Transmission Electron Microscopy (Journal Article)

IOP Conf. Ser.: Mater. Sci. Eng, (55), pp. 012005 , 2014.

(BibTeX)

Stephanie Vial Dmytro Nykypanchuk, Francis Leonard Deepak Marta Prado; Gan, Oleg

Plasmonic response of DNA-Assembled Gold Nanorods (AuNRs) (Journal Article)

Journal of Colloid and Interface Science, (433), pp. 34-42, 2014.

(BibTeX)

Yury V. Kolen’ko Manuel Bañobre-López, Carlos Rodríguez-Abreu Enrique Carbó-Argibay Francis Leonard Deepak Dmitri Petrovykh Fátima Cerqueira Saeed Kamali Kirill Kovnir Dmitry Shtansky Oleg Lebedev; Rivas, Jose

High-Temperature Magnetism as a Probe for Structural and Compositional Uniformity in Ligand-Capped Magnetite Nanoparticles (Journal Article)

J. Phys. Chem. C , (118), pp. 28322−28329, 2014.

(BibTeX)

Ana V. Silva Diana C. Leitao, Ricardo Ferreira Elvira Paz Francis Leonard Deepak Susana Cardoso; Freitas, Paulo

Linear nanometric tunnel junction sensors with exchange pinned sensing layer (Journal Article)

Journal of Applied Physics, (115), pp. 17E526, 2014.

(BibTeX)

Diana C. Leitao Elvira Paz, Ana Silva Anastasiia Moskaltsova Simon Knudde Francis Deepak Ricardo Ferreira Susana Cardoso; Freitas, Paulo

Nanoscale Magnetic Tunnel Junction sensing devices with soft pinned sensing layer and low aspect ratio (Journal Article)

IEEE Transactions on Magnetics, 50 , pp. 4410508, 2014.

(BibTeX)

GROUP LEADER

Leonard_Francis

THE TEAM

Anumol Ashokkumar
Research Fellow

Junjie Li
Research Fellow

Sharath Kumar
Master Student

Cherrelle Thomas
Scientific Visitor (UT-Austin, USA)

John Thomas
Scientific Visitor (University of Bangor, UK)

Irene Bechis
Summer Student (2017)

Joao Freitas
Summer Student (2017)

Markus Snellman
Summer Student (2017)

DESCRIPTION

Our research group in the Department of Advanced Electron Microscopy, Imaging and Spectroscopy (AEMIS) at INL is involved in understanding the atomic structure of materials (energy related and catalytically important materials) and correlating it with their properties using a combination of electron microscopic and spectroscopic tools. Understanding the structure of materials is fundamental to exploring their various interesting properties: magnetic, optical and optoelectronic. The studies are carried out by employing the state-of-the art aberration corrected S/TEM in combination with analytical electron microscopy to provide combined atomic structure – chemical sensitive information.

RESEARCH PROJECTS

The hollow interior core of nanotubes, both carbon and non-carbon (BN, WS2 etc.) provide the necessary space for the filling, encapsulation and confinement of molecules and crystals both organic and inorganic. In addition they provide templates for the formation of core-shell nanotubes. The reduced dimensionality of the encapsulated material as a consequence of “confinement” presents the advantage of different characteristics compared to that of the bulk material. The interaction between the encapsulated material and the host nanotube plays a crucial role and therefore can govern the structure and electronic properties of such a system.
In this project nanotubes (CNTs as well as Inorganic NTs) which provide accessible space for templated growth of nanotubes or nanorods within them are employed to encapsulate metal halides such as GdI3 and BiI3 which are contrast agents for biomedical imaging. Capillary filling is employed to encapsulate these metal halides within nanotubes of carbon and WS2 to obtain core-shell nanotubes and/or nanorods. Aberration Corrected Scanning/Transmission Electron Microscopy and Spectroscopy using Titan G2 80-200 TEM/STEM with ChemiSTEM Technology and FEI Titan Themis 60-300 kV is employed to characterize the atomic structure, morphology and composition of these core-shell structures.

Project2_picture

External Collaborations:
Dr. Pedro Costa and Nitin M. Batra (KAUST, Saudi Arabia)

Dr. Andrey Enyashin – Molecular Dynamics Simulation (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Publications
(1) Nitin M. Batra, E. A. Anumol, Jasmin Smajic, Andrey N. Enyashin, Francis Leonard Deepak and Pedro M. F. J. Costa, Morphological phase diagram of a metal halide encapsulated in carbon nanotubes, Submitted (2017).
(2) Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes, E. A. Anumol, A. N. Enyashin, N. M. Batra, P. M. F. J. Costa and Francis Leonard Deepak, Nanoscale, 2016, 8, 12170-12181.
(3) Capillary Imbibition of Gadolinium Halides into WS2 Nanotubes: A Molecular Dynamics View, Francis Leonard Deepak and A. N. Enyashin, Isr. J. Chem., 2016, doi:10.1002/ijch.201600055.

People in this Project: E.A. Anumol and Francis Leonard Deepak

In this project HAADF-STEM tomography is employed to obtain the 3D morphology of nanomaterials such as nanocatalysts and core-shell nanotubes. A Titan G2 80-200 TEM/STEM with ChemiSTEM Technology is used for this. EDX-STEM tomography is employed to obtain 3D chemical mapping. Low accelerating voltage (80 kV) enables tomography of beam sensitive materials such as carbon nanotubes. A high tilt tomography holder  and Super-X EDS detector (in the Titan ChemiSTEM) comprising four SDD detectors enable the EDX mapping in a wide tilt range (-70° to +70°) . Inspect 3D software is used for reconstruction and Amira for visualization.

Volume rendering of HAADF-STEM and EDS tomograms of GdI3@WS2 nanotube. (a) Nanotube positioned vertically. From left to right, HAADF-STEM tomogram, combined tomograms of each element and individual elemental tomograms are given. (b) Cross-sectional view of the nanotube. The elements are color coded as blue (W), green (S), yellow (Gd) and red (I).

Volume rendering of HAADF-STEM and EDS tomograms of GdI3@WS2 nanotube. (a) Nanotube positioned vertically. From left to right, HAADF-STEM tomogram, combined tomograms of each element and individual elemental tomograms are given. (b) Cross-sectional view of the nanotube. The elements are color coded as blue (W), green (S), yellow (Gd) and red (I).

 External Collaborations:

Dr. Pedro Costa and Mr. Nitin M. Batra (KAUST, Saudi Arabia)

Dr. Andrey Enyashin – Molecular Dynamics Simulation (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Publications

Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes, E. A. Anumol, A. N. Enyashin, N. M. Batra, P. M. F. J. Costa and Francis Leonard Deepak, Nanoscale, 2016, 8, 12170-12181.

People in this Project: Junjie Li and Francis Leonard Deepak

Uncovering atomic scale dynamical processes of lattice induced epitaxial growth of nanocrystal on the support is critical to understanding crystallization, solid-phase epitaxial growth, and advanced nanofabrication, all of which are linked to different important applications in material field.

HRTEM images taken under an electron dose of 2390 e/Å2sec revealing lattice induced interfacial Bi nucleation on SrBiTa2O9 substrate from stable nanocluster and structural fluctuations of the newly formed nanocrystal

HRTEM images taken under an electron dose of 2390 e/Å2sec revealing lattice induced interfacial Bi nucleation on SrBiTa2O9 substrate from stable nanocluster and structural fluctuations of the newly formed nanocrystal

External Collaborations:

Dr. Andrey Enyashin (Institute of Solid State Chemistry UB RAS Ekaterinburg, RUSSIAN FEDERATION).

Dr. Qiang Li (School of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China).

Dr. Zhongchang Wang (Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan).

Publications

  • In-situ Atomic-scale Observation of Droplets Coalescence Driven Nucleation and Growth at Liquid/Solid Interface, Junjie Li, Zhongchang Wang, Francis Leonard Deepak, Submitted, 2017.
  • Real-Time Dynamical Observation of Lattice Induced Nucleation and Growth in Interfacial Solid-Solid Phase Transitions, Junjie Li, Qiang Li, Zhongchang Wang, and Francis Leonard Deepak, Growth Des., 2016, 16, 7256−7262.

People in this Project: Junjie Li and Francis Leonard Deepak

 

Doping is an effective method to tune the electronic properties for MoS2 as well as other 2D semiconductors and has significant implications on their optical and electronic properties. In this project we fabricate doped MoS2 samples with different dopants and/or doping concentrations and study them employing high resolution imaging and spectroscopy.

External Collaborations:

Dr. G. Deokar (University of Namur, Belgium)

Publications

  • Geetanjali Deokar, Junjie Li, Francis Leonard Deepak, MoS2 nanoflowers, manuscript in prep.

People in this Project: Markus Snellman, E.A. Anumol, Junjie Li and Francis Leonard Deepak

 

Monometallic, Bimetallic and multimetallic core-shell nanoparticle/nanowire catalysts of noble metal alloys possesses superior activity, high selectivity and stability at low temperature compared to traditional bulk metals. This makes them ideal candidates for carrying out investigations on their structure, nature of alloy formation and thus understand the way the catalytic activity is enhanced. Bimetallic nanoparticles have two fundamental structures: a) alloys and b) core shell structures. There are several routes to the preparation of alloy nanoparticles both bimetallic and core-shell. Factors that will play a role in determining which of the two alternatives is more likely to occur include: the solubility of the metals, the relative surface energy, the kinetics of the synthesis and several others. Direct microscopic studies of various bimetallic nanoparticles have been carried out using high-resolution transmission electron microscopy (HRTEM). However, this method is limited because of the small difference in the lattice constant involved. Conventional transmission electron microscopy (CTEM) can produce chemical contrast due to due to different electron beam extinction distances. This has been applied successfully to image bimetallic nanoparticles down to 10 nm in diameter. Since the particles need to be in a low index zone orientation, this method is not easy to use in practice. As an alternative method of nanostructure determination high angle angular dark field (HAADF) imaging technique has been used successfully. The HAADF method has been used to detect variation in chemical composition down to single atom level in structures of nanosized particles. STEM-HAADF imaging carried out in an aberration corrected microscope reveals the atomistic structure and the alloying of bimetallic nanoparticles and nanowires. In combination with high resolution spectral and chemical analysis this techniques provides unprecedented information never obtained till date. Understanding the nature and structure of such bimetallic/multimetallic nanocatalysts is important to enable modification of their structure/morphology/composition and enhance their catalytic performance for fuel cells and other industrial applications.

HAADF images of a pair of Au-Ag Nanocages and their corresponding STEM-EDS

HAADF images of a pair of Au-Ag Nanocages and their corresponding STEM-EDS

External Collaborations:

Prof. M. Arturo López-Quintela (Dept. Physical Chemistry, Faculty of Chemistry Lab of Nanotechnology and Magnetism (NANOMAG) Research Technological Institute University of Santiago de Compostela)

Dr. P. John Thomas (School of Chemistry, Bangor University, Bangor, UK)

Prof. Maurizio Muniz-Miranda (“Ugo Schiff” Chemistry Dept, University of Florence)

Dr. Roberto Pilot (Consorzio INSTM and Department of Chemical Sciences, via Marzolo 1, 35131 Padova, Italy)

Dr. C.P. Vinod (Catalysis Division and Center of Excellence on Surface Science, CSIR National Chemical Laboratory, Pune, INDIA)

Dr. R. Nandini Devi (Catalysis Division, National Chemical Laboratory, Pune, India)

Publications

  • Magnetic Nanoparticles obtained by two-step Laser Ablation of Nickel and Silver in pure Water, Cristina Gellini, Francis Leonard Deepak, Maurizio Muniz-Miranda, Stefano Caporali, Francesco Muniz-Miranda, Alfonso Pedone, Claudia Innocenti, Claudio Sangregorio, Phys. Chem. C 2017, 121, 3597-3606.
  • A convenient route for Au@Ti-SiO2 nanocatalyst synthesis and its application for room temperature CO oxidation, Yogita Sonia, A. Anumol, Chandrani Nayak, Francis Leonard Deepak, C.P. Vinod, J. Phys. Chem. C 2017, 129, 4946-4957.
  • Understanding alloy structure and composition in sinter-resistant AgPd@SiO2 encapsulated catalysts and their effect on catalytic properties, Sourik Mondal, Thattarathody Rajesh, Basab B Dhar, Markus Snellman, Junjie Li, Francis Leonard Deepak, R. Nandini Devi, Submitted
  • Controlling Bimetallic Nanostructures by the Microemulsion Method with Subnanometer Resolution Using a Prediction Model, David Buceta, Concha Tojo, Miomir Vukmirovic, Francis Leonard Deepak, Arturo M. Lopez-Quintela, Langmuir, 2015, 31, 7435-7439.
  • Wavelength dispersion of the local field intensity in silver–gold nanocages, R. Pilot, Zoppi, S. Trigari, F. L. Deepak, E. Giorgetti and R. Bozio, Phys. Chem. Chem. Phys., 2015, 17, 7355.
  • Stable Ruthenium colloids by Laser Ablation, Brandi, S. Caporali, S. Cicchi, L. Lascialfari, M. Muniz-Miranda, S. Orazzini, M. Severi, Francis Leonard Deepak and E. Giorgetti, IEEE NANO, July 2015.
  • Advanced Methods of Electron Microscopy in Catalysis Research, Miguel Jose-Yacaman, Arturo Ponce-Pedraza, Sergio Mejía-Rosales and Francis Leonard Deepak, Advances in Imaging & Electron Physics (Academic Press), Editor: Peter Hawkes, vol. 177, pp: 279-342 (2013).

People in this Project: Sharath Kumar and Francis Leonard Deepak

The crystal structure of sodium titanate; the black framed area shows the unit cell of the structure.

The crystal structure of sodium titanate; the black framed area shows the unit cell of the structure.

 

The study is aimed at employing electron microcopy in combination with spectroscopic techniques to study these materials and provide an accurate and in-depth understanding into the various aspects related to their catalytic activity. The samples under consideration are transition metal modified TNTs which are prepared by cation exchange of the hydrothermally synthesized TNTs as well as doped TNTs. The techniques include employing Aberration Corrected Electron Microscopy (AC-TEM/STEM) along with the associated spectroscopic techniques, Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-Ray Spectroscopy (EDX), as this could provide the structure, composition and morphology of the specimen in a single experiment, from the same region, with high spatial resolution. Of particular importance would be the identification of the cations that are incorporated as dopants (and/or intercalated) and imaging them with single-atom sensitivity, along with elucidation of their oxidation/bonding states of undoped and doped samples (Ti4+ vs Co2+). It is expected that such a detailed experimental study using electron microscopy would provide new insights into the structural and compositional aspects which influences the catalytic properties.

External Collaborations:

Dr. Anabela Rolo (Dept. Physics, U. Minho, Braga, Portugal)

 

 

Ongoing National/European Projects

 

  • Regulatory testing of nanomaterials (NANoREG), FP7 Nanotechnologies & Nanosciences Thematic Cooperation Programme, Participant, Total funding: 242,000.00 €.
  • WATERNANOENV (National Project), Axencia Galega de Innovación  (GAIN)-ERDF Partners: Instituto Tecnológico de Galicia (ITG)-coordinator, Universidade de Santiago de Compostela (USC)-subcontracted and INL-subcontracted, INL budget: €395,000.
  • FCT-Algeria.
  • NORTE 2020 through the European Regional Development Fund (ERDF).

National and International Collaborations

 

  1. Minho, CICECO – U. Aveiro and INESC-MN (Portugal), USC (Spain), University of Florence (Italy), KAUST (Saudi Arabia), University of Bangor (U.K), NCL Pune (India), Ural Federal University (Russian Federation).

PUBLICATIONS

2017

Nitin M. Batra E. A. Anumol, Jasmin Smajic Andrey Enyashin Francis Leonard Deepak; Costa, Pedro

Morphological phase diagram of a metal halide encapsulated in carbon nanotubes (Journal Article)

Submitted, 2017.

(BibTeX)

Yogita Sonia E.A. Anumol, Chandrani Nayak Francis Leonard Deepak Vinod Phys

A convenient route for Au@Ti-SiO2 nanocatalyst synthesis and its application for room temperature CO oxidation (Journal Article)

Chem. C , 129 (4946-4957), 2017.

(BibTeX)

Sourik Mondal Thattarathody Rajesh, Basab Dhar Markus Snellman Junjie Li Francis Leonard Deepak Nandini Devi

Understanding alloy structure and composition in sinter-resistant AgPd@SiO2 encapsulated catalysts and their effect on catalytic properties (Journal Article)

Submitted , 2017.

(BibTeX)

Cristina Gellini Francis Leonard Deepak, Maurizio Muniz Miranda Stefano Caporali Francesco Muniz-Miranda Alfonso Pedone Claudia Innocenti; Claudio Sangregorio, Phys

Magneto-Plasmonic Colloidal Nanoparticles Obtained by Laser Ablation of Nickel and Silver Targets in Water (Journal Article)

Chem. C, (121), pp. 3597−3606, 2017.

(BibTeX)

Junjie Li Zhongchang Wang, Francis Leonard Deepak

In-situ Atomic-scale Observation of Droplets Coalescence Driven Nucleation and Growth at Liquid/Solid Interface (Journal Article)

Submitted, 2017.

(BibTeX)

2016

E. A. Anumol A. N. Enyashin, Batra Costa; Deepak, Francis Leonard

Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes (Journal Article)

Nanoscale, (8), pp. 12170-12181, 2016.

(BibTeX)

Deepak, Francis Leonard; Enyashin,

Capillary Imbibition of Gadolinium Halides into WS2 Nanotubes: A Molecular Dynamics View (Journal Article)

Isr. J. Chem., 2016.

(Links | BibTeX)

Junjie Li Qiang Li, Zhongchang Wang; Deepak, Francis Leonard

Real-Time Dynamical Observation of Lattice Induced Nucleation and Growth in Interfacial Solid-Solid Phase Transitions (Journal Article)

Cryst. Growth Des., Just Accepted Manuscript, 2016.

(Links | BibTeX)

J. Rodrigo Magana Yury V. Kolen’ko, Francis Leonard Deepak Conxita Solans Rekha Goswami Shrestha Jonathan Hill Katsuhiko Ariga Lok Kumar Shrestha; Rodriguez-Abreu, Carlos

From Chromonic Self-Assembly to Hollow Carbon Nanofibers for Efficient Materials in Supercapacitor and Vapor Sensing Applications (Journal Article)

ACS Applied Materials & Interfaces, 2016.

(Links | BibTeX)

2015

Francis Leonard Deepak Manuel Bañobre-López, Enrique Carbó-Argibay Fátima Cerqueira Yolanda Piñeiro-Redondo JoséRivas Corey Thompson Saeed Kamali Carlos Rodríguez-Abreu Kirill Kovnir; Kolenko, Yury

A Systematic Study of the Structural and Magnetic Properties of Mn‑, Co‑, and Ni-Doped Colloidal Magnetite Nanoparticles (Journal Article)

J. Phys. Chem C, (119), pp. 11947-11957, 2015.

(BibTeX)

David Buceta Concha Tojo, Miomir Vukmirovic Francis Leonard Deepak Arturo Lopez-Quintela

Controlling Bimetallic Nanostructures by the Microemulsion Method with Subnanometer Resolution Using a Prediction Model (Journal Article)

Langmuir, (31), pp. 7435-7439, 2015.

(BibTeX)

Eunice Cunha M. Fernanda Proença, Florinda Costa António Fernandes Marta Ferro Paulo Lopes Mariam Debs Manuel Melle-Franco Francis Leonard Deepak Maria Paiva

Self-assembled functionalized graphene nanoribbons from carbon nanotubes (Journal Article)

ChemistryOpen, (4), pp. 115 – 119, 2015.

(BibTeX)

Maryam Salimian Maxim Ivanov, Francis Leonard Deepak Dmitri Petrovykh Igor Bdikin Marta Ferro Andre Kholkin Elby Titus; Goncalves, Gil

Synthesis and characterization of reduced graphene oxide /spiky nickel nanocomposites for nanoelectronic applications (Journal Article)

J. Mater. Chem. C, (3), pp. 11516 – 11523, 2015.

(BibTeX)

R. Pilot A. Zoppi, Trigari Deepak Giorgettib; Bozioa,

Wavelength dispersion of the local field intensity in silver–gold nanocages (Journal Article)

Phys.Chem.Chem.Phys., (17), pp. 7355, 2015.

(BibTeX)

Nitin M Batra Shashikant P Patole, Ahmed Abdelkader Dalaver Anjum Francis Deepak; Costa, Pedro

Structural changes of electron and ion beam-deposited contacts in annealed carbon-based electrical devices (Journal Article)

Nanotechnology, (26), pp. 445301, 2015.

(BibTeX)

J. D. Costa S. Serrano-Guisan, Borme Deepak Tarequzzaman Paz J.Ventura Ferreira; Freitas,

Impact of MgO thickness on the performance of Spin Transfer Torque Nano-Oscillators​ (Journal Article)

IEEE Trans. Magn, (52), pp. 1401604, 2015.

(BibTeX)

2014

Francis Leonard Deepak Jose Rivas, Miguel Jose-Yacaman

Understanding the structure of nanocatalysts with High Resolution Scanning/ Transmission Electron Microscopy (Journal Article)

IOP Conf. Ser.: Mater. Sci. Eng, (55), pp. 012005 , 2014.

(BibTeX)

Stephanie Vial Dmytro Nykypanchuk, Francis Leonard Deepak Marta Prado; Gan, Oleg

Plasmonic response of DNA-Assembled Gold Nanorods (AuNRs) (Journal Article)

Journal of Colloid and Interface Science, (433), pp. 34-42, 2014.

(BibTeX)

Yury V. Kolen’ko Manuel Bañobre-López, Carlos Rodríguez-Abreu Enrique Carbó-Argibay Francis Leonard Deepak Dmitri Petrovykh Fátima Cerqueira Saeed Kamali Kirill Kovnir Dmitry Shtansky Oleg Lebedev; Rivas, Jose

High-Temperature Magnetism as a Probe for Structural and Compositional Uniformity in Ligand-Capped Magnetite Nanoparticles (Journal Article)

J. Phys. Chem. C , (118), pp. 28322−28329, 2014.

(BibTeX)

Ana V. Silva Diana C. Leitao, Ricardo Ferreira Elvira Paz Francis Leonard Deepak Susana Cardoso; Freitas, Paulo

Linear nanometric tunnel junction sensors with exchange pinned sensing layer (Journal Article)

Journal of Applied Physics, (115), pp. 17E526, 2014.

(BibTeX)

Diana C. Leitao Elvira Paz, Ana Silva Anastasiia Moskaltsova Simon Knudde Francis Deepak Ricardo Ferreira Susana Cardoso; Freitas, Paulo

Nanoscale Magnetic Tunnel Junction sensing devices with soft pinned sensing layer and low aspect ratio (Journal Article)

IEEE Transactions on Magnetics, 50 , pp. 4410508, 2014.

(BibTeX)

RESEARCH

DEPARTMENTS
aemicros.png
RESEARCH GROUPS
AEMIS_MICROSCOPY
AEMIS_SPECTROSCOPY