A5078511353- Perovskite Materials and Applications
- Silicon Nanostructures and Photoluminescence
- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Conducting polymers and applications
- Solid-state spectroscopy and crystallography
- Nanowire Synthesis and Applications
- Thin-Film Transistor Technologies
- Graphene research and applications
- Semiconductor materials and interfaces
- Ga2O3 and related materials
- Luminescence Properties of Advanced Materials
- Advanced Memory and Neural Computing
- Semiconductor materials and devices
- Photoreceptor and optogenetics research
- Organic Light-Emitting Diodes Research
- Silicon and Solar Cell Technologies
- Optical properties and cooling technologies in crystalline materials
- Carbon and Quantum Dots Applications
- Neuroscience and Neural Engineering
- Radiation Detection and Scintillator Technologies
- Crystal Structures and Properties
- Plasmonic and Surface Plasmon Research
- solar cell performance optimization
- Gold and Silver Nanoparticles Synthesis and Applications
Zhejiang University
2012-2025
Applied Physical Sciences (United States)
2019-2024
University of North Carolina at Chapel Hill
2020-2024
Communities In Schools of Orange County
2020-2021
Hangzhou Academy of Agricultural Sciences
2014-2017
State Key Laboratory of Silicon Materials
2014-2017
Hangzhou Xixi hospital
2015
Highly sensitive photodetection even approaching the single-photon level is critical to many important applications. Graphene-based hybrid phototransistors are particularly promising for high-sensitivity because they have high photoconductive gain due mobility of graphene. Given their remarkable optoelectronic properties and solution-based processing, colloidal quantum dots (QDs) been preferentially used fabricate graphene-based phototransistors. However, resulting QD/graphene face challenge...
Abstract Developing multijunction perovskite solar cells (PSCs) is an attractive route to boost PSC efficiencies above the single-junction Shockley-Queisser limit. However, commonly used tin-based narrow-bandgap perovskites have shorter carrier diffusion lengths and lower absorption coefficient than lead-based perovskites, limiting efficiency of perovskite-perovskite tandem cells. In this work, we discover that charge collection in PSCs limited by a short length electrons. Adding 0.03 molar...
State-of-the-art, high-performance perovskite solar cells (PSCs) contain a large amount of iodine to realize smaller bandgaps. However, the presence numerous vacancies at surface film formed by their evaporation during thermal annealing process has been broadly shown induce deep-level defects, incur nonradiative charge recombination, and photocurrent hysteresis, all which limit efficiency stability PSCs. In this work, modifying defective films with cadmium iodide (CdI2) effectively reduces...
Ravishankar et al. claimed the drive-level capacitance profiling (DLCP) method cannot resolve trap density along depth direction in perovskites with given thickness, and explained measured charges to be a consequence of geometrical diffusion capacitance. We point out that densities DLCP are derived from differential at different frequencies, thus background caused by geometry has been subtracted. Even for non-differential doping analysis DLCP, contribution is shown negligible excluded....
The defective bottom interfaces of perovskites and hole-transport layers (HTLs) limit the performance p-i-n structure perovskite solar cells. We report that addition lead chelation molecules into HTLs can strongly interact with lead(II) ion (Pb 2+ ), resulting in a reduced amorphous region near passivated surface. minimodule an aperture area 26.9 square centimeters has power conversion efficiency (PCE) 21.8% (stabilized at 21.1%) is certified by National Renewable Energy Laboratory (NREL),...
Abstract A low defect density in metal halide perovskite single crystals is critical to achieve high performance optoelectronic devices. Here we show the reduction of grown by a ligand-assisted solution process with 3‐(decyldimethylammonio)‐propane‐sulfonate inner salt (DPSI) as an additive. DPSI ligands anchoring lead ions on crystal surfaces not only suppress nucleation solution, but also regulate addition proper growing surface, which greatly enhances quality. The CH 3 NH PbI better...
Tailoring the doping of semiconductors in heterojunction solar cells shows tremendous success enhancing performance many types inorganic cells, while it is found challenging perovskite because difficulty perovskites a controllable way. Here, small molecule 4,4',4″,4″'-(pyrazine-2,3,5,6-tetrayl) tetrakis (N,N-bis(4-methoxyphenyl) aniline) (PT-TPA) which can effectively p-dope surface FAx MA1-x PbI3 (FA: HC(NH2 )2 ; MA: CH3 NH3 ) films reported. The intermolecular charge transfer property...
Polycrystalline perovskites can be readily fabricated into large areas using solution depositions; however, they suffer from dark currents that are tens to hundreds times higher than industrially relevant values, limiting their application in low-dose x-ray detection. Here, we show the of a heterojunction structure polycrystalline films significantly reduces current density by more 200 subnanoampere per square centimeter without reducing sensitivity detectors. The perovskite formed...
Abstract Perovskite light‐emitting diodes (PeLEDs) are promising candidates for display and solid‐state lighting, due to their tunable colors, high conversion efficiencies, low cost. However, the performance of blue PeLEDs is far inferior that near‐infrared, red, green counterparts. Here, fabrication pure‐blue with an emission peak at 475 nm, a external quantum efficiency 10.1%, maximum luminance 14 000 cd m −2 demonstrated by tailoring compositions perovskites. The electroluminescence...
Abstract High‐performance tin‐lead perovskite solar cells (PSCs) are needed for all‐perovskite‐tandem cells. However, iodide related fast photodegradation severely limits the operational stability of Sn‐Pb perovskites despite demonstrated high efficiency and thermal stability. Herein, this work employs an alkylammonium pseudo‐halogen additive to enhance power conversion (PCE) photostability methylammonium (MA)‐free, PSCs. Density functional theory (DFT) calculations reveal that...
Narrow-bandgap (NBG) tin (Sn)-lead (Pb) perovskites generally have a high density of unintentional p-type self-doping, which reduces the charge-carrier lifetimes, diffusion lengths, and device efficiencies. Here, p-n homojunction across Sn-Pb perovskite is demonstrated, results from gradient doping by barium ions (Ba2+ ). It reported that 0.1 mol% Ba2+ can effectively compensate p-doping or even turns it to n-type without changing its bandgap. cations are found stay at interstitial sites...
Abstract Interstitial iodides are the most critical type of defects in perovskite solar cells that limits efficiency and stability. They can be generated during solution, film, device processing, further accelerating degradation. Herein, we find introducing a small amount zinc salt- trifluoromethane sulfonate (Zn(OOSCF 3 ) 2 solution control iodide resultant perovskites ink films. CF SOO ̶ vigorously suppresses molecular iodine formation by reducing it to iodide. At same time, cations...
Abstract Perovskite photovoltaics have been shown to recover, or heal, after radiation damage. Here, we deconvolve the effects of based on different energy loss mechanisms from incident protons which induce defects can promote efficiency recovery. We design a dual dose experiment first exposing devices low-energy efficient in creating atomic displacements. Devices are then irradiated with high-energy that interact differently. Correlated modeling, (with increased ionizing component)...
Localized surface plasmon resonance (LSPR) of doped Si nanocrystals (NCs) is critical to the development Si-based plasmonics. We now experimentally show that LSPR can be obtained from both B- and P-doped NCs in mid-infrared region. Both experiments calculations demonstrate Drude model used describe if dielectric screening carrier effective mass are considered. When doping levels B P similar, energy B-doped higher than because more efficiently activated produce free carriers NCs. find...