LABORATORY FOR SYNTHESIS and CRYSTALLOGRAPHY OF FUNCTIONAL MATERIALS
08/2021
Our new paper in Advanced Optical Materials is out!
The performance of quasi-2D perovskite light emitting diodes (LEDs) with mixed small cations, cesium and formamidinium (FA), is significantly affected by their ratio. The best devices obtained for Cs:FA ratio of 1:1 exhibit a maximum external quantum efficiency (EQE) of 12.1%, maximum luminance of 15 070 cd m−2 and maximum current efficiency of 46.1 cd A−1, which is significantly higher (about 3 times) compared to devices with FA only (maximum EQE of 4.1%, maximum luminance of 4521 cd m−2) and Cs-only (maximum EQE of 4.0%, maximum luminance of 4886 cd m−2). The photoluminescence quantum yield of the Cs:FA 1:1 sample is similarly enhanced, 21.3% compared 5.4% and 6%, for FA-only and Cs-only samples, respectively. It can be observed that the Cs:FA ratio significantly affects the crystallization of the perovskite, with the optimal 1:1 ratio resulting in the formation of tetragonal Cs0.5FA0.5PbBr3 phase (different from cubic FAPbBr3 and orthorhombic CsPbBr3) with pronounced preferential orientation as well as a significant reduction in the trap density, which leads to a substantial improvement in the light-emitting performance.
07/2021
News from our PEROEXPLORE project
Our project team consisting of scientists from the Department of Materials Physics (Jasminka Popović, Juraj Ovčar and Sanja Burazer) and the Department of Theoretical Physics (Ivor Lončarić and Luca Grisanti) and colleagues from the Department of Physics, Faculty of Science (Željko Skoko) and Hong Kong University (Aleksandra Djurišić) during the first 18 months of research conducted within the project “2D and quasi-2D perovskiti: from targeted structural design to improved efficiency and stability” (HRZZ-PZS-2019-02-2068) clearly demonstrated the exceptional importance of synergy between a large number of different experimental methods and advanced theoretical calculations for understanding and improving the optoelectronic performance of perovskite light emitting diodes.
06/2021
Our new paper in Inorganic Chemistry is out!
05/2021
New postdoc joined our laboratory! Welcome Lidija!
Dr. Lidija Kanižaj , winner of 2020 LOREAL-UNESCO Award for Women in Science, is our new postdoc at PEROEXLORE project
04/2021
Our new paper in Advanced Functional Materials is out!
04/2021
Let's clean up for O-ZIP!
It is a time to say goodbye to the past and say hello to the future!
Welcome to our new XRD laboratory that has been totally revamped in joint efforts with our dear friends from Laboratory for chemical and biological crystallography
THE BRAIN
03/2021
Happy Easter!
03/2021
We are seeking for a motivated postdoc researcher with expertise in perovskites and crystallography to join our project team!
02/2021
Visit from our partners from HRZZ
We've presented the results of our PEROEXLORE project to the our partners from HRZZ.
02/2021
New equipment purchased and installed thanks to our 2DPEROEXLORE projects financed by HRZZ and ESF
UV/Vis and PL spectrophotometers for solid-state samples
The novel high-temperature polymorph of sodium imidazolate reported in this paper was discovered in the mechanochemical reaction of NaIm with NaBH4 and later prepared directly by thermal treatment of the room-temperature polymorph of NaIm. Solid-state NMR was used for initial elucidation of structural features; the crystal structure was determined by single-crystal X-ray diffraction, while the in situ HT-XRPD experiments utilizing synchrotron radiation have been performed in order to gain the insight into the structural evolution and thermal stability, in addition to differential thermal analysis and hot-stage microscopy measurements. Contrary to the RT polymorph that forms a dense and hypercoordinated structure without pores, the high-temperature polymorph of NaIm exhibits pores of 50 Å3 that suggest possible application for gas sorption/separation. It is important to highlight that, once formed, the high-temperature polymorph of NaIm retains its structure and remains stable at room temperature.
01/2021
Our new paper in Crystal Growth & Design is out!
