A5061548243- ZnO doping and properties
- Quantum Dots Synthesis And Properties
- Optical Coatings and Gratings
- Photonic and Optical Devices
- Plasmonic and Surface Plasmon Research
- Perovskite Materials and Applications
- Optical Polarization and Ellipsometry
- Organic Electronics and Photovoltaics
- Chalcogenide Semiconductor Thin Films
- Nanowire Synthesis and Applications
- Surface Roughness and Optical Measurements
- Ga2O3 and related materials
- Photonic Crystals and Applications
- Gas Sensing Nanomaterials and Sensors
- Conducting polymers and applications
- Organic Light-Emitting Diodes Research
- Advanced Fiber Optic Sensors
- solar cell performance optimization
- Electromagnetic Scattering and Analysis
- Near-Field Optical Microscopy
- Optical and Acousto-Optic Technologies
- Numerical methods in inverse problems
- Mechanical and Optical Resonators
- Copper-based nanomaterials and applications
- Spectroscopy and Chemometric Analyses
City University of Hong Kong
2013-2024
The electrical and optical properties of cadmium oxide indicate that thin films the material could be good transparent electrodes for high-efficiency multijunction solar cells, though its complex dielectric function depends drastically on carrier concentration. This comprehensive study correlates CdO's gap, free-carrier absorption, refractive index, high-frequency constant, electron effective mass with dopant concentration species. These results are crucial engineering optoelectronic devices...
The effects of gold nanoparticles (AuNPs) incorporated in the hole transporting layer (HTL) poly[[4,8-bis[(2-ethylhexyl)oxy] benzo[1,2-b:4,5-b′] dithiophene-2, 6-diyl] [3-fluoro-2-[(2-ethylhexy)carbonyl]thieno[3,4-b]thiophened iyl]] (PTB7): [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) based solar cells are being systematically investigated terms optical properties, electrical and photovoltaic performance. impacts AuNPs on response devices modeled by finite-difference time-domain...
High performance organic photovoltaic devices typically rely on type‐II P/N junctions for assisting exciton dissociation. Heremans and co‐workers recently reported a high efficiency device with third layer which is spatially separated from the active junction; but still contributes to carrier generation by passing its energy junction via long‐range transfer mechanism. In this study authors show that there an additional mechanism contributing efficiency. Some bipolar materials (e.g.,...
We investigate the low-cost, earth-abundant and air-stable inorganic absorber Sb<sub>2</sub>S<sub>3</sub>that can be processed in air for organic–inorganic hybrid solar cell applications.
In this work, we have synthesized Cd1-xGaxO1+δ alloy thin films at room temperature over the entire composition range by radio frequency magnetron sputtering. We found that with high Ga contents of x > 0.3 are amorphous. Amorphous alloys in < 0.5 exhibit a electron mobility 10-20 cm2 V-1 s-1 resistivity 10-2 to 10-4 Ω cm range. The amorphous can also be controlled 5 orders magnitude from 7 × 77 controlling oxygen stoichiometry. Over range, these crystalline and large tunable intrinsic band...
Abstract Optical sensors using zero‐reflection points (ZRPs) enable excellent sensitivity due to the accompanying phase singularities and steepest slope of reflectivity curve. Here, collaborative manipulation three ZRPs in a simple platform formed by lithography‐free, metal‐dielectric‐metal structure with unsurpassed, experimentally demonstrated, limit detection ≈2 × 10 −8 refractive index unit is reported. The sensor relies on: i) strong coupling between p ‐polarized surface plasmon...
Abstract Electromodulation (EM) spectroscopy, a powerful technique to monitor the changes in polarizability p and dipole moment u of materials upon photo-excitation, can bring direct insight into excitonic properties materials. However, extracting Δ from electromodulation spectrum relies on fitting with optical absorption where effect different device geometries might introduce large variation extracted values. Here, we demonstrate systematic study various approaches both commonly adopted...
Optical spectroscopy and imaging provide non-destructive, contactless, fast strategies to study the nature technological aspects of thin films nanostructured materials for photonic optoelectronic applications. Furthermore, design, engineering, optimization such devices requires quantitative information with high-precision standards in measuring modelling as is case, example, determination optical critical dimension (OCD) semiconductor industry. Our application these tunable self-assembled...
Non-destructive, contactless, and fast optical spectroscopy imaging strategies provide great advantages for the modelling optimization of thin films nanostructured materials in photonic optoelectronic applications. In particular, accurate, high-precision determination dispersion properties sub-wavelength remains challenging overlooked despite its massively demonstrated need benefits to semiconductor industry. Over years, our group has used these study self-assembled nanolasers, hybrid...
Abstract Significant enhancement of the light emission in Ruddlesden–Popper organic–inorganic halide perovskites is obtained by antisolvent induced spontaneous formation nanocrystals an amorphous matrix. This morphology change results passivation defects and significant 16 times higher photoluminescence quantum yield (PLQY), it applicable to different spacer cations. The use trioctylphosphine oxide further defect leading increase PLQY (≈2.3 times), suppression lower energy low temperature...
Abstract We present evidence of amplified emission mediated by surface plasmon polaritons (SPPs) from a CdS 0.2 Se 0.8 nanoribbon (NR) supported on gold-coated silicon substrate. Room temperature is observed the above excitation irradiances ~25 W/cm 2 when it gold coated The shown to act as resonator cavity, leading amplification discrete wavelengths in spectrum. Evidence for formation SPP waves between substrate and resulting wavenumber increase allows matching theoretical resonance with...
We study light absorption in ZnO nanorod arrays sensitized with CdSe quantum dots as one of the factors affecting solar cell performance need improvement given their current well below expectations. Light trapping (NRAs) it relates to array density and length dot (QD) loading is studied using Finite Difference Time Domain model. It shown that such architecture a sensitive function morphological dimensions higher NRA does not necessarily correspond large cell. Instead, efficiency depends...
CdO-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> alloy films (Cd xmlns:xlink="http://www.w3.org/1999/xlink">1-x</sub> Ga xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> xmlns:xlink="http://www.w3.org/1999/xlink">1+δ</sub> ) over the whole composition range (x=0 to 1) were synthesized by room temperature radio frequency magnetron sputtering. We found that intrinsic band gap of...