Παρουσίαση διδακτορικής διατριβής του κ. Αλέξανδρου Δελτσίδη
13 Δεκεμβρίου 2024
Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής του
κ. Αλέξανδρου Δελτσίδη
Επιβλέπων: κ. Λάππας Αλέξανδρος, Διευθυντής Ερευνών,
Ινστιτούτου Ηλεκτρονικής Δομής και Λέιζερ του Ιδρύματος Τεχνολογίας Έρευνας, Ηράκλειο Κρήτης
(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)
Την Παρασκευή 20 Δεκεμβρίου 2024 και ώρα 9:30 στην αίθουσα Τηλεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής του υποψήφιου διδάκτορα του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Αλέξανδρου Δελτσίδη, με θέμα:
«Electron Correlations in Layered Metal Chalcogenides: Structure and Physical Properties»
Abstract
Intercalation of layered iron chalcogenide superconductors with guest species gives access to a gallery of layered phases with enhanced superconducting properties. In these systems, emerging empirical pictures imply a strong relation of the average and local structure with the magnitude of the superconducting transition temperature . Exploring the puzzling saturation of at large interlayer separations, , (average structure), and the role of the geometry of the basic building FeSe4 block (local structure) in tuning the strength of electronic correlations and spin dynamics in these systems, offers an avenue to parameterize conditions that facilitate high . This thesis focuses on variant phases of the Lix(C5H5N)yFe2-zSe2 system with very large .
High-throughput, time-resolved X-ray total scattering, has been employed to establish conditions that enable the synthesis of phase pure product and simultaneously identify the different length-scales that emerge during the growth of the Lix(C5H5N)yFe2-zSe2 expanded lattice phase. In-situ pair distribution function analysis revealed local distortions, involving swollen FeSe4 edge-sharing units, as a consequence of the electron-donating moieties being accommodated in the interlayer space. These non-trivial local distortions were further explored by element-specific (Fe and Se K-edge) X-ray absorption spectroscopy as a function of temperature and the Li content. The work found progressive softening and stretching of the electronically active Fe-layer with elevated Li content—effects that were associated with the presence of Fe-site vacancies. Annealing Lix(C5H5N)yFe2-zSe2 forms a phase with reduced and somewhat lower —an outcome of the modified metal-ligand environment due to reduced doping level. Local structure insights suggest that empirical local structure metrics for growth may become less relevant when the layers are spaced far away. Instead, other parameters such as electron doping level may come into play to leverage high .
Different aspects of the magnetism of these systems are imprinted in two different time scales. These were probed with X-ray emission spectroscopy and inelastic neutron scattering. The Fe Kβ emission spectra shed light on the evolution of instantaneous spin dynamics (10-15 s) and found evidence of strong localized magnetism in the normal state which, due to strong quantum fluctuations, is severely quenched in the superconducting state. However, Hund's coupling appears to play a key role in mediating the development of local moments when cooling towards the correlated state. Inelastic neutron spectra probed the correlated spin dynamics (10- 12 s) and failed to identify strong resonant signals in the superconducting state—akin to similar unconventional systems—enquiring about the role of electronic correlation strength and doping in dampening the intensity of such signals. Insights on the spin-dynamics suggest that intercalation brings about large spin disorder in the normal state, raising questions about the nature of unconventional pairing interactions in systems with very large .
The outcomes highlight that intercalation by insertion of molecular donors in-between the electronically active iron-layers is a viable tool to develop and design the properties of high- Fe-chalcogenides. The sensitive response of their structure on carrier doping points that when interlayer separation is enhanced, reduces electronic screening that aligns with the concept of Hund’s coupling that is central in modifying the pairing strength and further optimizations of superconductivity.
Νέες Θέσεις για Διδακτορικές Σπουδές με Υποτροφία στο Τμήμα Χημικών Μηχανικών του Πανεπιστημίου Πατρών
13 Δεκεμβρίου 2024
Δείτε σχετικά το
σύνδεσμο.
Call for postgraduate positions Spring Semester 2024-2025
13 Δεκεμβρίου 2024
The Department of Materials Science and Engineering of the University of Crete announces a limited number of postgraduate student positions for enrolment in the spring semester of the academic year 2024-2025.
The aim of the Postgraduate Program in Materials Science and Engineering of the Materials Science and Engineering Department is to prepare MSc students for excellent career prospects in the rapidly growing interdisciplinary field of Materials Science and Engineering. The educational and research activities of the program provide an integrated approach and in-depth training, with emphasis on conducting innovative research in the following cutting-edge fields of Materials Science Engineering and Technology:
- Optoelectronics – Magnetic materials – Nanotechnology
- Polymers – Colloids
- Theoretical – Computational Materials Science
- Synthetic Chemistry of Materials
- Biomaterials – Biomolecules
Successful completion of the Postgraduate Program leads to a Postgraduate Diploma (MSc) after 4 semesters of study that include the mandatory attendance of courses and the preparation and writing of a Master’s Thesis. The program is in English and requires full-time participation. As part of their training, postgraduate students assist in the instruction of undergraduate courses.
Graduates of the first cycle of studies of Greek universities or similar institutions abroad have the right to apply for the program. Knowledge of English is required. There are no tuition fees for students coming from the European Economic Area (EEA). For students coming from countries outside of the EEA, the program’s total tuition fees are 2000 Euro.
The academic criteria that are taken into account for the selection are defined in the Postgraduate Studies Regulations. They include the undergraduate degree, grades in courses related to the subject of the program, the performance in a diploma thesis, if provided in the first cycle of studies, as well as the relevant research or professional activity of the candidate.
Necessary supporting documents
(submitted exclusively in electronic form through the website https://postgrad.cict.uoc.gr )
- Application
- Detailed CV
- Report of interests
- Copy of degree
- Diploma supplement
- Up to three (3) letters of recommendation
- Any other document the candidate considers to substantiate scientific excellence and quality
- Certificate of a good knowledge of the English language (B2 level and above)
Please use the form templates found here: https://mscs.uoc.gr/dmst/?page_id=850
The application must include ane-mail account from which you will be informed about the progress of your application.
Letters of recommendation will be sent directly by the authors to the postgraduate secretariat.
Deadline for submission of the application and supporting documents for the Postgraduate Program is set for January 17th, 2025. The interviews will take place on January 27th, 2025 between 10:00 – 13:00. There is the possibility of a video conference for candidates living outside Crete.
Applications and supporting documents are submitted exclusively online via the website https://postgrad.cict.uoc.gr. Candidates should a) create a user account, b) process their application by filling in the corresponding fields and uploading files for the remaining data, and c) make the final submission before the deadline.
For more information, please contact the Secretariat of the Department of Materials Science and Engineering:
Mr. Ch. Stratigis: tel. +30 2810-394272, stratigis@materials.uoc.gr,
and Ms Sygelaki Fotini: tel. +30 2810394270, fsygelaki@materials.uoc.gr,
or the Director of Postgraduate Studies, Assoc. Prof. D. Papazoglou: postgrad_chair@materials.uoc.gr.
Μετεγγραφές στο ΤΕΜΥ 2024
11 Δεκεμβρίου 2024
Καλούνται οι φοιτητές των οποίων εγκρίθηκε από το Υπουργείο Παιδείας, Θρησκευμάτων και Αθλητισμού η αίτηση μετεγγραφής στο Τμήμα Επιστήμης και Μηχανικής Υλικών του Πανεπιστημίου Κρήτης, να αποστείλουν ηλεκτρονικά (secretariat@materials.uoc.gr) ή να προσκομίσουν στη Γραμματεία του Τμήματος από την Τετάρτη 12/12/2024 έως και την Παρασκευή 20/12/2024 τα παρακάτω δικαιολογητικά για τον έλεγχο της μετεγγραφής κατά την ισχύουσα νομοθεσία. Θα πρέπει οπωσδήποτε να αποστείλουν:
- Την εκτύπωση της οριστικοποιημένης ηλεκτρονικής αίτησης μετεγγραφής που φέρει αριθμό πρωτοκόλλου
- Τα δικαιολογητικά που αναφέρονται στην αίτηση, κατά περίπτωση.
- Βεβαίωση Εγγραφής από το Τμήμα προέλευσης στην οποία να αναφέρεται το εξάμηνο φοίτησης
Μετά τον έλεγχο των δικαιολογητικών, οι φοιτητές θα λάβουν με e-mail από την Γραμματεία επιβεβαίωση της εγκυρότητας της μετεγγραφής τους και θα τους δοθεί εύλογο χρονικό διάστημα για την προσκόμιση της βεβαίωσης διαγραφής από το Τμήμα προέλευσης, προκειμένου να ολοκληρωθεί η εγγραφή τους στο Τμήμα μας. Σε καμία περίπτωση δεν πρέπει να προχωρήσουν στην διαγραφή από το Τμήμα προέλευσης αν δεν λάβουν την επιβεβαίωση εγκυρότητας της μετεγγραφής τους από τη Γραμματεία μας.
Στο παρακάτω αρχείο μπορείτε να δείτε τη σχετική εγκύκλιο του Υπουργείου.
Συνημμένο αρχείο:
Εγκύκλιος δικαιολογητικών
ΠΡΟΣΚΛΗΣΗ ΑΠΟΚΤΗΣΗΣ ΑΚΑΔΗΜΑΪΚΗΣ ΕΜΠΕΙΡΙΑΣ ΕΑΡΙΝΟ ΕΞΑΜΗΝΟ Ακ. Έτους 2024-25_ΤΜΗΜΑ ΕΠΙΣΤΗΜΗΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ ΥΛΙΚΩΝ Π.Κ.
10 Δεκεμβρίου 2024
Δείτε τη σχετική
Πρόσκληση.
Παρουσίαση διδακτορικής διατριβής της κ. Λέιλας Ζουρίδη
10 Δεκεμβρίου 2024
Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής
της κ. Λέιλας Ζουρίδη
Επιβλέπων Καθηγητής: Βασίλειος Μπίνας
(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)
Την Πέμπτη 19 Δεκεμβρίου 2024 και ώρα 9:00 στην αίθουσα Τηλεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής της υποψήφιας διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Λέιλας Ζουρίδη, με θέμα:
«Development of perovskite oxides as printable solid oxide cell electrodes»
Abstract
The energy transition from fossil fuels to an electrified hydrogen energy economy still faces challenges on the implementation of electrolyzer and fuel electrochemical cells due to complexity of fabrication and materials cost. In this study the investigation of versatile perovskite oxide materials as printed thin-film electrode components for facile manufacturing of solid oxide cells is presented. The implementation of mechanochemical synthesis on the solid-state synthesis of electroceramics directly from salt precursors has been explored for the preparation of easy to handle and abundant titanate and manganite perovskites, followed by the physicochemical characterization of their structural, morphological, elemental, electrical and thermal stability properties in ex-situ and in-situ conditions. The pure perovskite phase was achieved after high temperature annealing solely in the cases where the mechanochemical step was implemented, while other synthetic procedures tested at similar synthetic conditions produced mostly mixed metal oxides, indicating the potential of the solvent-free direct salt precursor mechanochemical synthesis developed in this work. Ink development and study of dispersions based on organic solvents with our synthesized materials was implemented with different processing methods to achieve optimal, inkjet-printable inks, with appropriate shelf-life and print fidelity. The optimized inks were then utilized in an inkjet printing system to study their deposition by altering parameter conditions on the cartridge and platen for consistent drop generation and precision on the deposited patterns. Comparatively, different thick pastes were developed with the perovskite oxides, to be used by two additional additive manufacturing methods, screen printing and direct-ink-writing. Fabrication of electrolyte-supported solid oxide cells was conducted with different designs to explore the extend of applicability of the printing methods. After fabrication of solid oxide cells, the electrochemical evaluation of electrodes on air and hydrogen fuel was conducted illustrating their potential as electrodes for reversible solid oxide cells.
Παρουσίαση διδακτορικής διατριβής της κ. Ελευθερίας Δαριβιανάκη
10 Δεκεμβρίου 2024
Πρόσκληση σε Δημόσια Παρουσίαση της Διδακτορικής Διατριβής της
κ. Ελευθερίας Δαριβιανάκη
Επιβλέπων Καθηγητής: Κωνσταντίνος Στούμπος
(Σύμφωνα με το άρθρο 95, παρ. 3 του Ν. 4957/2022, ΦΕΚ 141 τ. Α΄/21.7.2022)
Την
Τρίτη 17 Δεκεμβρίου 2024 και ώρα
11:00 στην
αίθουσα Τηλεκπαίδευσης Ε130 του Τμήματος Μαθηματικών και Εφαρμοσμένων Μαθηματικών του Πανεπιστημίου Κρήτης, θα γίνει η δημόσια παρουσίαση και υποστήριξη της Διδακτορικής Διατριβής της υποψήφιας διδάκτορος του Τμήματος Επιστήμης και Μηχανικής Υλικών κ. Ελευθερίας Δαριβιανάκη, με θέμα:
«Halide Perovskite Solar Cells and Heterostructures»
Abstract
Halide perovskites semiconductors are in the spotlight of modern research, exceling in many fields of optoelectronics, with the major attention drawn in solar cell applications, due to their exceptional solar cell performance. However, there are several hurdles that the perovskite solar cells need to overcome, such as their limited long-term stability, which constitutes the main obstacle for the commercialization of this promising photovoltaics technology.
In this dissertation, we deal with the fabrication of single-junction perovskite solar cell devices with the aim to improve the stability of photovoltaic devices at ambient conditions. Perovskite solar cells were fabricated using different fabrication thin-film deposition techniques, with a major focus on the two-step immersion method. The optimum perovskite films, achieved under ambient conditions, show an enhancement of the devices towards environmental stability and photostability. However, the photovoltaic conversion efficiency (PCE) of the devices remains low, as a result of interface resistance which limits the photo-generated carriers’ extraction.
Attempting to overcome this barrier, and in order to obtain better charge-transport characteristics, we have switched to an alternative charge-transport layer by introducing GaAs instead of TiO2, used as an ETL layer. Thus, a major part of this work relates to the fabrication of hybrid perovskite/GaAs nanowire heterostructures. In this direction, we have successfully managed to fabricate hybrid perovskite/GaAs nanowire diodes with promising I-V characteristics, following a suitable n+-type doping of the GaAs nanowire ETL layer. These devices showed up a measurable photo-response when illuminated, but did not produce a competitive photocurrent value at this point. We attribute the observed loss of current in the current architecture design, which does not permit the full illumination of the active area of the device. Future directions include the use of Transparent Conducting Oxide (TCO) materials as top electrodes, or the improvement of the structural design of the device to enable effective illumination of the active area of the solar cell.
The present Thesis, represents a new direction in the development of perovskite-based solar cells and draws several important conclusions concerning the interfacing of halide perovskites with non-oxidic based heterojunctions. Since, the vast majority of the experimental work was performed at ambient conditions, the perovskite stability assessment presented here, could be instructive for addressing the long-term stability problem of halide perovskite semiconductors.
Πρόγραμμα Ελληνοβρετανικής Συνεργασίας για την χορήγηση υποτροφιών βραχείας διάρκειας στο πλαίσιο μεταπτυχιακών και διδακτορικών σπουδών – Ακαδημαϊκό έτος 2024-2025
09 Δεκεμβρίου 2024
Δείτε τη σχετική
ιστοσελίδα του ΙΚΥ.
Παρουσίαση πτυχιακής εργασίας του κ. Τ. Σιαμάνη
06 Δεκεμβρίου 2024
Η ΠΑΡΟΥΣΙΑΣΗ ΔΙΠΛΩΜΑΤΙΚΗΣ ΕΡΓΑΣΙΑΣ
Του φοιτητή Σιαμάνη Τριανταφύλλου Τριαντάφυλλου,
θα γίνει την
Δευτέρα 9/12/2024 και ώρα 11:00
στην αίθουσα Β2 στο κτήριο του τμήματος Χημείας
Θέμα Διπλωματικής:
«Καθαρισμός και μελέτες προετοιμασίας της πρωτεΐνης PGL-3 για sm-FRET»
Διμελής Επιτροπή: Φιλιππίδη Εμμανουέλα, Lavigne Matthieu
Abstract:
Η διπλωματική εργασία επικεντρώθηκε στον καθαρισμό και την προετοιμασία για χρήση της μεθόδου μοριακής μεταφοράς ενέργειας Förster στο επίπεδο του ενός μορίου (smFRET) της πρωτεΐνης PGL-3, μιας κρίσιμης πρωτεΐνης στη βιολογία της γονιμοσποράς του C. elegans. Η έρευνα επικεντρώθηκε τις μοριακές λεπτομέρειες της πρωτεϊνικής δομής, συμβάλλοντας στην προώθηση της κατανόησης των δομικών χαρακτηριστικών της PGL-3.
This thesis centers on the purification and preparation for single-molecule Förster resonance energy transfer (smFRET) experiments of the PGL-3 protein, a pivotal component in C. elegans germline biology. The research delves into the molecular intricacies of PGL-3, contributing to the understanding of PGL-3's structural attributes.
Ανακοίνωση για τη Διεθνή Ημέρα για την Εξάλειψη της Βίας κατά των Γυναικών
26 Νοεμβρίου 2024
Δείτε τη σχετική
ανακοίνωση.
