A5087277985- Perovskite Materials and Applications
- Chalcogenide Semiconductor Thin Films
- Conducting polymers and applications
- Quantum Dots Synthesis And Properties
- Organic Light-Emitting Diodes Research
- Solid-state spectroscopy and crystallography
- Organic Electronics and Photovoltaics
- solar cell performance optimization
- Enzyme Structure and Function
- Photovoltaic System Optimization Techniques
- Stellar, planetary, and galactic studies
- Advanced Electron Microscopy Techniques and Applications
- Solar Radiation and Photovoltaics
- Photosynthetic Processes and Mechanisms
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Force Microscopy Techniques and Applications
- ZnO doping and properties
- Catalysis and Hydrodesulfurization Studies
- Origins and Evolution of Life
- Tuberculosis Research and Epidemiology
- Astronomical and nuclear sciences
- Optical properties and cooling technologies in crystalline materials
- Pulsars and Gravitational Waves Research
- Space Science and Extraterrestrial Life
University of Sharjah
2012-2023
University of Cambridge
2016-2020
Cavendish Hospital
2016-2020
Bridge University
2020
Masdar Institute of Science and Technology
2015
Lead-halide perovskites have emerged as high-performance photovoltaic materials. We mapped the propagation of photogenerated luminescence and charges from a local photoexcitation spot in thin films lead tri-iodide perovskites. observed light emission at distances ≥50 micrometers found that peak internal photon spectrum red-shifts 765 to ≥800 nanometers. used lateral-contact solar cell with selective electron- hole-collecting contacts charge extraction for >50 away arose repeated recycling...
Halide perovskites are found to exhibit strain patterns over large areas, which influences the lifetimes of charge carriers.
We report significant improvements in the optoelectronic properties of lead halide perovskites with addition monovalent ions ionic radii close to Pb2+. investigate chemical distribution and electronic structure solution processed CH3NH3PbI3 perovskite structures containing Na+, Cu+, Ag+, which are lower valence metal than Pb2+ but have similar radii. Synchrotron X-ray diffraction reveals a pronounced shift main peaks for cation-based films, suggesting incorporation these cations into lattice...
Metal-halide perovskites show remarkably clean semiconductor behaviour, as evidenced by their excellent solar cell performance, in spite of the presence many structural and chemical defects. Here, we how this performance sets during earliest phase conversion from metal salts organic-based precursors solvent, using simultaneous situ synchrotron X-ray operando current–voltage measurements on films prepared interdigitated back-contact substrates. These structures function working cells soon...
Abstract We explore the degradation behaviour under continuous illumination and direct oxygen exposure of inverted unencapsulated formamidinium(FA) 0.83 Cs 0.17 Pb(I 0.8 Br 0.2 ) 3 , CH NH PbI 3−x Cl x perovskite solar cells. continuously test devices in-situ in-operando with current-voltage sweeps, transient photocurrent, photovoltage measurements, find that in cells due to occurs over shorter timescales than FA mixed-cation devices. attribute these oxygen-induced losses power conversion...
Synchrotron grazing incidence WAXS is used to track CH<sub>3</sub>NH<sub>3</sub>PbI<sub>3</sub> precursor and perovskite crystallites rotation <italic>in situ</italic> during solution-deposition thermal annealing.
Scanning nanofocus X-ray diffraction (nXRD) performed at a synchrotron is used for the first time to simultaneously probe morphology and structural properties of spin-coated CH3NH3PbI3 (MAPI) perovskite films photovoltaic devices. MAPI are on Si/SiO2/PEDOT:PSS substrate held different temperatures during deposition in order tune film coverage, then investigated by nXRD, scanning electron microscopy (SEM) grazing incidence wide angle scatter-ing (GI-WAXS). The advantages nXRD over SEM GI-WAXS...
In this paper a modeling method is investigated that finds the non-linear equation parameters of photovoltaic (PV) module in order to obtain desired PV model using any circuit simulator. This adjusts I-V curve at three remarkable points: open voltage, short current, and maximum power point [1]. Three models are realized technique namely, single-diode model, two-diode three-diode model. The evaluation study accuracy these showed relative errors ranging from 32% 50%. Further, improved by...
The incorporation of noble metal nanoparticles, displaying localized surface plasmon resonance, in the active area donor-acceptor bulk-heterojunction organic photovoltaic devices is an industrially compatible light trapping strategy, able to guarantee better absorption incident photons and give efficiency improvement between 12% 38%. In present work, we investigate effect Au Ag nanoparticles blended with P3HT: PCBM on P3HT crystallization dynamics by synchrotron grazing incidence X-ray...
Perovskite solar cells (PSCs) have reached a formidable power conversion efficiency of 25.7% over the years development. One strategies that has been responsible for development stable and highly efficient PSCs is modifications monovalent A‐site cations (methylammonium, MA; formamidinium, FA; cesium, Cs, etc.) in lead halide perovskites. Herein, impact modifying cation (MA, FAMA, CsFAMA, potassium‐passivated rubidium‐passivated CsFAMA) perovskite on their optoelectronic, charge transport,...
Interdigitated back-contact (IBC) architectures are the best performing technology in crystalline Si (c-Si) photovoltaics (PV). Although single junction perovskite solar cells have now surpassed 23% efficiency, most of research has mainly focussed on planar and mesostructured architectures. The number studies involving IBC devices is still limited proposed unfeasible for large scale manufacturing. Here we discuss importance as a powerful tool investigating fundamental working mechanisms...
The effect of incorporating 2.85 nm red luminescent silicon nanoparticles as photoluminescence down-shifters on the efficiency organic solar cells based regioregular poly(3-hexylthiophene-2,5-diyl) and [6,6]-phenyl-C71-butyric acid methyl ester is investigated. are deposited by spin coating inkjet printing different layers devices. presence in does not result any performance improvement causes a significant degradation power conversion efficiency.
Metal halide perovskites are attracting tremendous interest for a variety of optoelectronic applications. The ability to tune the perovskite bandgap by tweaking chemical compositions opens up new applications as coloured emitters and components tandem photovoltaics. Nevertheless, non-radiative losses still limiting performance, with luminescence yields in state-of-the-art solar cells far from 100% under illumination conditions. Furthermore, mixed systems designed continuous tunability...
We mapped the propagation of photogenerated luminescence and charges from a local photoexcitation spot in thin films lead tri-iodide perovskites using confocal microscopy setup with independent excitation collection objectives. observed regenerated PL emission at distances as far 50 micrometers away photoexcitation. then made scratch film to increase out-scattering found that peak internal photon spectrum red-shifts 765 ≥800 nanometers. This is caused by sharp decay absorption coefficient...
In this paper a modeling method is investigated that finds the non-linear equation parameters of photovoltaic (PV) module in order to obtain desired PV model using any circuit simulator. This adjusts I-V curve at three remarkable points: open voltage, short current, and maximum power point [1]. Three models are realized technique namely, single-diode model, two-diode three-diode model. The evaluation study accuracy these showed relative errors ranging from 32% 50%. Further, improved by...
Halide perovskites are promising semiconductors for inexpensive, high-performance optoelectronics. Despite a remarkable defect tolerance compared to conventional semiconductors, perovskite thin films still show substantial microscale heterogeneity in key properties such as luminescence efficiency and device performance. This behavior has been attributed spatial fluctuations the population of sub-bandgap electronic states that act trap-mediated non-radiative recombination sites. However,...
Venkatraman ‘Venki’ Ramakrishnan is the President of The Royal Society and Group Leader at MRC Laboratory Molecular Biology. In 2009 he shared Nobel Prize in Chemistry ‘for studies structure function ribosome’. this interview explains why governments should invest more basic scientific research rather than simply on applied science engineering. He also discusses interdisciplinarity, collaborations, public engagement.
Didier Queloz is Professor of Physics at the Cavendish Laboratory (University Cambridge) and Geneva University. He was jointly awarded 2019 Nobel Prize in for “the discovery an exoplanet orbiting a solar-type star”. In first part his conversation with Mejd Alsari he discusses impact 1995 on theory planetary systems formation.
Professor Didier Queloz talks about his challenging journey from the discovery of first exoplanet orbiting a solar-type star in 1995 to acknowledgement by scientific community. He explores experience reporting paradigm-changing finding and how this triggered hard scepticism publishing industry fellow scientists, which lasted 3 years. Michel Mayor were eventually acknowledged as founders new field exoplanets awarded Nobel Prize for Physics 2019.