ΠΑΡΟΥΣΙΑΣΗ ΜΕΤΑΠΤΥΧΙΑΚΗΣ ΕΡΓΑΣΙΑΣ του κ. Απόστολου Παντούσα

20 Ιουνίου 2023

Τίτλος

« Synthesis and Characterization of 2D Layered Halide Perovskite Quantum Wells»

Υπότιτλος:

Synthesis and characterization of the (CH3(CH2)5NH3)2(CH3NH3)n-1PbnBr3n+1 homologous series.

του Απόστολου Παντούσα

μεταπτυχιακού φοιτητή του Τμήματος Επιστήμης και Τεχνολογίας Υλικών του Πανεπιστημίου Κρήτης

Επιβλέπων Καθηγητής: Κωνσταντίνος Στούμπος

Τρίτη 27 Ιουνίου 2023

Ώρα 12:00

H παρουσίαση θα πραγματοποιηθεί στην αίθουσα Β2, στο κτήριο του Τμήματος Χημείας, του Πανεπιστημίου Κρήτης

Abstract Perovskites are a class of semiconducting materials with great interest in optoelectronic applications due to their high efficiency, high absorption coefficients and low cost. Two-dimensional (2D) perovskite structures provide the ability to further tune these properties and manufacture high-performance devices . In this work, we focus on the synthesis and characterization of a new homologous series of 2D layered lead halide perovskites based on the CH3NH3PbBr3 bulk perovskite. The homologous series, with general formula (CH3(CH2)5NH3)2(CH3NH3)n-1PbnBr3n+1, where n corresponds to the number of layers of the perovskite, produces a fertile ground for the study of quantum wells, since the alternating organic and inorganic layers generate a natural, periodic quantum well structure . By tuning the thickness, we control the degree of dielectric and quantum confinement of the photogenerated carriers inside the inorganic layers, thus creating a series of compounds with tunable optical properties in the visible spectrum range. The compounds were synthesized in pure form and their crystal structure was determined via single-crystal X-ray diffraction. The structural phase transitions were monitored via Differential Scanning Calorimetry (DSC) in the -80 – 120 oC temperature range while the optical properties were studied via steady-state and time-resolved photoluminescence (PL) spectroscopy in the -195- 25 oC temperature range. The results suggest that the new compounds are excellent excitonic model systems and can be employed in specific applications like LEDs and lasers.