A5027916101- Perovskite Materials and Applications
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Conducting polymers and applications
- Solid-state spectroscopy and crystallography
- Magnetic and transport properties of perovskites and related materials
- Catalysis and Oxidation Reactions
- Organic Light-Emitting Diodes Research
- Crystal Structures and Properties
- Catalytic Processes in Materials Science
- Advanced Photocatalysis Techniques
- Health and Wellbeing Research
- Molecular Junctions and Nanostructures
- Thin-Film Transistor Technologies
- Advanced Chemical Physics Studies
- Surface Chemistry and Catalysis
- Advancements in Solid Oxide Fuel Cells
- Solid State Laser Technologies
- Advanced Fiber Laser Technologies
- Luminescence Properties of Advanced Materials
- Semiconductor Quantum Structures and Devices
- Optical properties and cooling technologies in crystalline materials
- Random lasers and scattering media
- Intergenerational Family Dynamics and Caregiving
- Electronic and Structural Properties of Oxides
University of Cambridge
2019-2025
Diamond Light Source
2023
National Cheng Kung University
2016-2022
Abstract Understanding the fundamental properties of buried interfaces in perovskite photovoltaics is paramount importance to enhancement device efficiency and stability. Nevertheless, accessing poses a sizeable challenge because their non‐exposed feature. Herein, mystery interface full stacks deciphered by combining advanced situ spectroscopy techniques with facile lift‐off strategy. By establishing microstructure–property relations, basic losses at contact are systematically presented, it...
Abstract Large datasets are now ubiquitous as technology enables higher-throughput experiments, but rarely can a research field truly benefit from the data generated due to inconsistent formatting, undocumented storage or improper dissemination. Here we extract all meaningful device peer-reviewed papers on metal-halide perovskite solar cells published so far and make them available in database. We collect over 42,400 photovoltaic devices with up 100 parameters per device. then develop...
The fabrication of multidimensional organometallic halide perovskite via a low-pressure vapor-assisted solution process is demonstrated for the first time. Phenyl ethyl-ammonium iodide (PEAI)-doped lead (PbI2 ) spin-coated onto substrate and subsequently reacts with methyl-ammonium (MAI) vapor in heating oven. doping ratio PEAI MAI-vapor-treated has significant impact on crystalline structure, surface morphology, grain size, UV-vis absorption photoluminescence spectra, resultant device...
Stable but not quite cubic The black, photoactive phase of formamidinium (FA) perovskites, which is usually stabilized by cation alloying to avoid the formation inactive hexagonal phases, assumed be cubic. High-resolution microscopy studies Doherty et al . using nanoscale probes revealed that these FA-rich phases are rather undergo slight tilting (by two degrees) octahedra. Black can have localized regions nucleate degradation. Surface-bound ethylenediaminetetraacetic acid tilted pure FA...
It is common practice in the lead halide perovskite solar cell field to add a small molar excess of iodide (PbI2) precursor solution increase device performance. However, recent reports have shown that an PbI2 can accelerate performance loss. In addition, photoactive (band gap ∼2.3 eV), which may parasitic absorption losses cell. Here we show devices using quantities exhibit better as compared with stoichiometric devices, both initially and for duration stability test under operating...
All-perovskite tandem solar cells beckon as lower cost alternatives to conventional single-junction cells. Solution processing has enabled rapid optimization of perovskite technologies, but new deposition routes will enable modularity and scalability, facilitating technology adoption. Here, we utilize 4-source vacuum deposit FA0.7Cs0.3Pb(IxBr1-x)3 perovskite, where the bandgap is changed through fine control over halide content. We show how using MeO-2PACz a hole-transporting material...
While perovskite-based photovoltaics is progressing toward commercialization, it remains an open question which fabrication technology – solution-based, vapor-based, or combinations will pave the way to faster economic breakthrough.
This work explores electrochemical impedance spectroscopy to study recombination and ionic processes in all-perovskite tandem solar cells. We exploit selective excitation of each subcell enhance or suppress the signal from subcell, allowing individual subcells. use this methodology show that resistance time constants wide gap are increased with passivation. Furthermore, we investigate subcell-dependent degradation during maximum power point tracking find an increase a decrease capacitance...
Halide perovskites of the form ABX3 have shown outstanding properties for solar cells. The highest reported compositions consist mixtures A-site cations methylammonium (MA), formamidinium (FA) and cesium, X-site iodide bromide ions, are produced by solution processing. However, it is unclear whether processing will yield sufficient spatial performance uniformity large-scale photovoltaic modules or compatibility with deposition multilayered tandem cell stacks. In addition, volatile MA cation...
Abstract Halide perovskites are excellent candidate materials for use in solar cell, LED, and detector devices, part because their composition can be tuned to achieve ideal optoelectronic properties. Empirical efficiency optimization has led the field toward compositions rich FA (formamidinium) on A‐site I X‐site, with additional small amounts of MA (methylammonium) or Cs cations Br X‐site anions. However, it is not clear how why specific alloyed, that is, mixed component, halide relate...
All-perovskite tandem solar cells represent a significant advancement in next-generation photovoltaics toward higher power conversion efficiencies than single junction cells. A critical component of monolithic cell is the interconnecting layer, which facilitates integration wide bandgap and low subcells. Conventional designs all-perovskite are based on an ultrathin metal recombination typically Au, alongside poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) hole transporting...
Perovskite-based tandem solar cells are of increasing interest as they approach commercialization. Here we use experimental parameters from optical spectroscopy measurements to calculate the limiting efficiency perovskite–silicon and all-perovskite two-terminal tandems, employing currently available bandgap materials, 42.0% 40.8%, respectively. We show luminescence coupling between subcells (the transfer photons high-bandgap low-bandgap subcell) relaxes current matching when subcell is a...
Hybrid-perovskite-based optoelectronic devices are demonstrating unprecedented growth in performance, and defect passivation approaches highly promising routes to further improve properties. Here, the effect of molecular ion BF4−, introduced via methylammonium tetrafluoroborate (MABF4) a surface treatment for MAPbI3 perovskite, is reported. Optical spectroscopy characterization shows that introduction leads reduced non-radiative charge-carrier recombination with reduction first-order rate...
Vapor‐based deposition technique is considered as a promising approach for preparing high‐quality and uniform perovskite thin film. With evolution from coevaporation to low‐pressure vapor‐assisted solution process, both energy budget reaction yield film fabrications are improved. In this paper, hybrid chemical vapor (LPHCVD) method applied fabricate CH 3 NH PbI films. The crucial dependence of working pressure on the formation revealed. Moreover, time plays an important role in controlling...
Bandgap tunability of lead mixed-halide perovskites makes them promising candidates for various applications in optoelectronics since they exhibit sharp optical absorption onsets despite the presence disorder from halide alloying. Here we use localization landscape theory to reveal that static due compositional alloying iodide:bromide perovskite contributes at most 3 meV Urbach energy. Our modelling reveals reason this small contribution is effective masses perovskites, resulting a natural...
Microscopy provides a proxy for assessing the operation of perovskite solar cells, yet most works in literature have focused on bare thin films, missing charge transport and recombination losses present full devices. Here we demonstrate multimodal operando microscopy toolkit to measure spatially correlate nanoscale losses, chemical composition. By applying this same scan areas state-of-the-art, alloyed cells before after extended operation, show that devices with highest macroscopic...
Metal halide perovskite-based artificial leaves have emerged in recent years as a promising design towards direct solar fuel synthesis. However, the complexity of these layered devices and reliance on solution-based...
Thermal co-evaporation of halide perovskites is a solution-free, conformal, scalable, and controllable deposition technique with great potential for commercial applications, particularly in multi-junction solar cells.
Colloidal quantum dots (QDs) have illuminated computer monitors and television screens due to their fascinating color-tunable properties depending on the size. Here, electroluminescence (EL) wavelength of perovskite LEDs was tuned via atomic layer number (ALN) nanoplates (NPs) instead "size" in conventional QDs. We demonstrated efficient with controllably tailored emission from n = 3, 4, 5, ≥7 ALN NPs specific discrete major peaks at 607, 638, 669, 728 nanometers. These peak external...
Mixed-halide mixed-cation hybrid perovskites are among the most promising perovskite compositions for application in a variety of optoelectronic devices due to their high performance, low cost, and bandgap-tuning capabilities. Instability pathways such as those driven by ionic migration, however, continue hinder further progress. Here, an operando variable-pitch synchrotron grazing-incidence wide-angle X-ray scattering technique is used track surface bulk structural changes mixed-halide...
In this report, we fabricated thiocyanate-based perovskite solar cells with low-pressure vapor-assisted solution process (LP-VASP) method. Photovoltaic performances are evaluated detailed materials characterizations. Scanning electron microscopy images show that SCN-based films using LP-VASP have long-range uniform morphology and large grain sizes up to 1 μm. The XRD Raman spectra were employed observe the characteristic peaks for both pure CH3 NH3 PbI3 perovskite. We observed Pb(SCN)2 film...