BrainMap

Mr. Liviu Cristian Tanase

Scientific Researcher (CS)

Postdoctoral Researcher - FRITZ HABER INSTITUT DER MAX PLANCK GESSELSCHAFT

Other affiliations

Scientific Researcher (CS) - INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (Romania)

Researcher

Web of Science ResearcherID: I-2747-2012

Expertise & keywords

CHEMISTRY AND PHOTOCHEMISTRY ON FERROELECTRIC SURFACES Call name: Projects for Young Research Teams - RUTE -2014 call
PN-II-RU-TE-2014-4-0456 2015 - 2017

Role in this project:

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Project website: http://www.infim.ro/ro/projects/chimie-si-fotochimie-la-suprafete-feroelectrice

Abstract:

This Project is concentrated on a detailed study of the intimate processes occurring when molecules are adsorbed, desorbed or are reacting at atomically clean, well characterized, single crystal ferroelectric surfaces synthesized by pulsed laser deposition (PLD). In situ investigations will be carried out by a multitude of surface science techniques: X-ray photoelectron spectroscopy, X-ray photoelectron diffraction, low energy and reflection high energy electron diffraction (LEED and RHEED), mass spectroscopy, aiming to seek adsorptions, desorptions and molecular reactions when the ferroelectric polarization is triggered by external parameters (optically, thermally or by charge carrier injection). The goal of this project will be a detailed description of the molecular processes occurring at ferroelectric surfaces (lead zirco-titanate and barium titanate, also combined with noble metals as co-catalysts – Ag, Au, Pt, Pd), mainly involving molecular reactions of actual interest for automotive industry: (i) oxidation of carbon monoxide; (ii) reduction of nitric or nitrous oxide (NOx); (iii) combined reaction pathways for three way catalysts. The results of the Project will be helpful for the development of new catalytic converters, cheaper, operating at lower temperatures and whose activity may be triggered optically or electrically. The main output will consist in scientific papers in top tier ISI journals and possibly a patent application towards the end of the Project.

Integrated nanosystems for solar fuel generation Call name: Projects for Young Research Teams - RUTE -2014 call
PN-II-RU-TE-2014-4-1384 2015 - 2017

Role in this project:

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Project website: http://infim.ro/ro/projects/nanosisteme-integrate-pentru-generarea-solara-de-combustibili

Abstract:

The project “Integrated nanosystems for solar fuel generation” aims the development of a bi- and/or multi-component ensemble mainly based on ferroelectric materials able to efficiently split the water and to perform the CO2 reduction under sunlight irradiation. To reach the project main goals different approaches will be studied. One approach is to develop operational OER and HER/CRR powder catalysts based on earth-abundant and stable ferroelectric materials, which finally to be able to perform easily water oxidation and CO2 reduction processes on their surfaces. Co-catalysts for both category of transformations will be loaded on the surface of the semiconductors in order to reduce each reaction overpotential. Another approach is to develop these materials in different morphologies (nanowires, nanotrees or thin films) and to check the stability and optimize their photocatalytic performances under different reaction conditions. The as prepared photocatalytic systems will be firstly tested in separate reaction conditions and later on coupled through an ohmic contact into an integrated nanosystem. The expected results from this project would make a major contribution to Romanian excellence and competitiveness in this research field.

Magnetoelectric coupling at interfaces of ferroelectric/ferromagnetic heterostructures Call name: Projects for Young Research Teams - RUTE -2014 call
PN-II-RU-TE-2014-4-1117 2015 - 2017

Role in this project:

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Project website: http://www.infim.ro/ro/projects/cuplajul-magnetoelectric-la-interfa%C8%9B-feroelectricferomagnetic

Abstract:

The project aims in revealing the nature of magnetoelectric (ME) coupling at ferroelectric/

ferromagnetic interfaces by means of X-ray and ultra-violet spin-angle-resolved photoelectron spectroscopy depending on the buffer layer termination. Metallic perovskite oxides such as hole-doped LaxSr1-xMnO3 buried under a thin layer of n-doped BaTiO3 will be investigated. This approach would further allow for a reversible ON/OFF magnetization switching by means of an external applied electric field. A crucial role in the heterostructures, who exhibit ME coupling, is the interface hybridization between the empty d orbitals of the ferroelectric and filled d orbitals of the metallic perovskite which are responsible for the magnetic moment. Employing linear dichroism in photoemission performed at Synchrotron line, the degree of orbital polarization as well as symmetry of the bonding states will be established. The magnetic order will be assessed by angle-resolved PES with spin resolution. The approach will reveal the spectroscopic manifestations of the polarization and magnetic order switching on the electronic states near the Fermi level, which are involved in conductivity and therefore in the tunneling electroresistance and tunneling magnetoresistance readout in non-volatile memories. In addition, the Mott spin detector available at our experimental setup from at Elettra Synchrotron line in Trieste will allow for the first time the access at the buried interfaces with spin resolution.

Innovative technologies for III-V photovoltaic convertors Call name: Joint Applied Research Projects - PCCA 2013 - call
PN-II-PT-PCCA-2013-4-1054 2014 - 2017

Role in this project:

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO); UNIVERSITATEA BUCURESTI (RO); OMEGA PROFESIONAL SRL (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Project website: http://www.infim.ro/ro/projects/tehnologie-inovativa-pentru-convertori-fotovoltaici-din-compusi-iii-v

Abstract:

In this period of modern industry development that requires different energy sources, a solution in good viability with environmental protection is the use of photovoltaic cells for direct conversion of Sun energy. In the development of PV and TPV applications there are three vectors involved that are: efficiency, temperature resistance and the cost. The gallium antimonide (GaSb) is the basis of the most PV cells in modern TPV systems and its innovative technology based on modern ultra-high vacuum techniques assures for the present project a good efficiency to cost ratio on the PV market. GaSb is a III-V semiconductor compound with zinc blende crystal structure and has an energy gap of 0.726 eV and is worth to mention that the structure GaAs/GaSb has set a record for solar cell efficiency of 35% opening a new era for photovoltaics applications. We can say that in this view the GaSb photosensitive structures offers the possibility of an almost total conversion of sun energy from visible spectrum to heat transform in electricity by TPV effect. This project is related to an end product from a III-V compounds, where the candidate is a well defined structure developed from Molecular Beam Epitaxy (MBE) facilities grown in GaSb system, respectively AlGaSb/GaSb. The main parameter subjected to bend engineering is the semiconductor gap that can be changed in ternary or quaternary compounds by selecting the relative proportion of element in the compound. This offers the possibility of designing PV converters with small band gap, suitable for TPV applications, where the IR radiation can be absorbed ( the project proposes an experiment of a sensor to YAG:Nd laser radiation). In this project we intend to use the technological achievements reached in the study of the III-V compounds from our group, with the purpose to attend a viable GaSb based PV converter starting from n-type single crystal. This is a new way open for our technological facilities in situ procedures that assures the possibility to use MBE for epitaxial layers, experience and performance in contact deposition together with photolithography for contact grid. The preliminary treatment of the surface structures as the information raised from various investigation techniques (e.g. X-Ray Photoelectron Spectroscopy-XPS) deeply affected the electrical characteristics of the device. Epilayers quality will be investigated in situ by XPS,UPS, AES and STM techniques that are available in the Project infrastructure at the coordinating organisation –National Institute of Materials Physics.The ohmic contacts investigated for lightly doped n-GaSb will be in the system Au/Ni/Au, Au(Ge)/Ni/Au and Cr-Au on p-AlGaSb. The theoretical study of a PV-TPV structure related to fundamental aspects of semiconductor devices operation is in the general trend and strategy of the Department of Electricity, Solid State and Biophysics from Faculty of Physics, Bucharest and from this point of view the project integration will be very good. Is worth to mention that the quality of the work involved in this project is expected to attract an educational impact that means that we expect to manage the work for students at master level and probably for PhD. The novelty of the elements involved in obtaining a performance GaSb/AlxGa1-xSb structure will be a part of the scientific results presented to be published in different ISI journals. The market potential of the present project will be valued by our partners from economy, namely SC Omega Profesional SRL and SC ANDISOR TERMO SRL. At these partners will be developed studies of solar energy concentration systems, will be available a solar panel with 5-7 converters of GaSb and at the end of the project will be attend an elaboration of measurement protocol for PV structures and establishment of referee parameters and quality matrix in the facilities of a new and well equipped Solar Energy Testing Laboratory.

High temperature, high stability, low cost evaporation cells for molecular beam epitaxy Call name: Joint Applied Research Projects - PCCA-2011 call, Type 2
PN-II-PT-PCCA-2011-3.2-0767 2012 - 2016

Role in this project:

Coordinating institution: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA

Project partners: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO); INSTITUTUL NATIONAL DE CERCETARE DEZVOLTARE PENTRU TEHNOLOGII IZOTOPICE SI MOLECULARE I N C D T I M (RO); BRAVA 2000 S.R.L. (RO)

Affiliation: INSTITUTUL NATIONAL DE CERCETARE - DEZVOLTARE PENTRU FIZICA MATERIALELOR BUCURESTI RA (RO)

Project website: http://www.infim.ro/projects/celule-de-evaporare-la-temperaturi-mari-stabilitate-ridicata-si-cost-redus-pentru-depuneri

Abstract:

Evaporation cells based on a new heating principle will be designed, fabricated and tested. This heating principle is based on direct resistive heating of two concentric tubes made on a refractory metal (Ta, Mo, W), with thin walls (0.1-0.2 mm), subject to a high electrical current (60-100 A). The inner pipe contains the material to be evaporated. The outer pipe, which also warms up, acts at the same time as a thermal screen for the inner pipe: as a consequence, higher temperatures are achieved in the inner part and also a higher amount of power is dissipated inside the inner pipe. The warming up to very high temperatures (over 2000 C) proceeds in a few tens of seconds, to be compared with several tens of minutes in standard evaporation cells where a crucible is warmed by using a W filament. Also, a precise temperature calibration may be obtained as function of the heating current only, whereas in conventional cells thermocouples are used. These thermocouples require additional vacuum current feedthroughs and also their thermal contact to the crucible may be problematic. A third advantage of the new principle is its relative low cost, based on the fact that the only expensive parts are the refractory material pipes. A new concept (dismountable assembly) will be developed also for the water cooling of the cell, whereas a single high current vacuum feedthrough is sufficient. One anticipates easy and fast manufacture of such devices, resulting in low delivery terms, as compared with 3-6 months for the actual evaporators. The estimated market is of some 500-1000 units in the European Community, whereas the stipulated benefit is of 5000 Euro per unit. The project will (i) implement the new heating principle; (ii) implement the new water cooling principle; (iii) achieve accuracte temperature calibration; (iv) demonstrate the ability to evaporate at high temperature, especially of metals that are usually evaporated by electron bombardment: Ti, Cr, V, Zr, Nb.

FILE DESCRIPTION	DOCUMENT
List of research grants as project coordinator or partner team leader
Significant R&D projects for enterprises, as project manager
R&D activities in enterprises
Peer-review activity for international programs/projects