A5088039746- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Advanced Battery Technologies Research
- Transition Metal Oxide Nanomaterials
- Extraction and Separation Processes
- Catalysis and Oxidation Reactions
- Supercapacitor Materials and Fabrication
- Advanced battery technologies research
- Conducting polymers and applications
- Chemical Synthesis and Characterization
- CO2 Reduction Techniques and Catalysts
- Microbial Fuel Cells and Bioremediation
- Polyoxometalates: Synthesis and Applications
- Microbial Metabolic Engineering and Bioproduction
- Catalytic Processes in Materials Science
- Adsorption and biosorption for pollutant removal
- Thermal Expansion and Ionic Conductivity
- Inorganic Fluorides and Related Compounds
- Advanced Sensor and Energy Harvesting Materials
- Molecular Junctions and Nanostructures
- Force Microscopy Techniques and Applications
- Anaerobic Digestion and Biogas Production
- Magnetic confinement fusion research
- Anodic Oxide Films and Nanostructures
- Constructed Wetlands for Wastewater Treatment
Tsinghua University
2022-2025
Tsinghua–Berkeley Shenzhen Institute
2022-2025
University Town of Shenzhen
2022-2023
Massachusetts Institute of Technology
2016-2020
Binghamton University
2013-2019
Brookhaven National Laboratory
2016
Beihang University
2011-2013
Electrochemical kinetics of Li-ion battery cathodes are measured at single-particle level and combined with transmission X-ray microscopy to elucidate behavior during use.
Lithium-rich layered oxides (LLOs) are concerned as promising cathode materials for next-generation lithium-ion batteries due to their high reversible capacities (larger than 250 mA h g-1 ). However, LLOs suffer from critical drawbacks, such irreversible oxygen release, structural degradation, and poor reaction kinetics, which hinder commercialization. Herein, the local electronic structure is tuned improve capacity energy density retention rate performance of via gradient Ta5+ doping. As a...
Abstract Solid‐state electrolytes (SSEs) have been regarded as the most attractive candidate for safe and high‐energy lithium (Li) batteries of next generation. However, inability current SSEs to keep up with performance requirements is significantly affected by complex factors, especially ionic conductivity, mechanochemical properties, coupled ion/electron reaction at electrified interfaces. Strategies in solid electrolyte chemistries technologies are put forward overcome these challenges...
Abstract As a promising candidate for the flame‐retardant electrolyte, triethyl phosphate (TEP)/potassium bis(fluorosulfonyl)amide (KFSI)‐based electrolyte has drawn much attention in K‐ion battery community. Although TEP/KFSI formula at moderate main salt concentration (normally, <3 m ) enables compatibility of reactive K metal anode, long‐standing oxidative instability KFSI remains unsolved. Here, an additive strategy is reported to address high‐voltage issue and generalize it other...
Abstract Advancements in portable electronic devices and electric powered transportation has drawn more attention to high energy density batteries, especially lithium–sulfur batteries due the low cost of sulfur its density. However, battery is still quite far from commercialization mostly because incompatibility between all major components battery—the cathode, anode, electrolyte. Here a methodology demonstrated that shows promise significantly improving stability by multilayer encapsulation...
In this work, we demonstrate the stable cycling of more than one Li in solid-state-synthesized ε-LiVOPO4 over 20 cycles for first time. Using a combination density functional theory (DFT) calculations, X-ray pair distribution function (PDF) analysis and absorption near edge structure (XANES) measurements, present comprehensive thermodynamics, kinetics, structural evolution ε-LixVOPO4 entire lithiation range. We identify two intermediate phases at x = 1.5 1.75 low-voltage regime using DFT...
Significance It is possible to nearly double the energy density of existing lithium-ion batteries by using lithium metal anodes. However, it has been known for decades that dendrites and mossy formed during charging (electrodeposition) limit cycle life batteries. important change growth behavior metal, which closely related properties solid–electrolyte interface (SEI) via spontaneous reactions between electrolyte. In this experimental-modeling integrated study, we reveal design principles...
Abstract Rechargeable aluminum ion batteries (AIBs) are one of the most promising battery technologies for future large‐scale energy storage due to their high theoretical volumetric capacity, low‐cost, and safety. However, low capacity intercalation‐type cathode materials reduces competitiveness AIBs in practical applications. Herein, a conversion‐type FeF 3 ‐expanded graphite (EG) composite is synthesized as novel material with good conductivity cycle stability. Combined introduction...
We have investigated the possibility of molybdenum substitution into ε-VOPO4 structure and its effects on electrochemical performance this material as a cathode in Li-ion battery. found that up to 5% Mo can substitute V upon hydrothermal synthesis at 180 °C with further annealing 550 °C. The is confirmed by increase unit cell volume content. A combination X-ray absorption photoelectron spectroscopy, magnetic studies, density functional theory calculations indicates an Mo6+ oxidation state...
The epsilon polymorph of vanadyl phosphate ε-VOPO4 is a promising cathode material for high-capacity Li ion batteries, owing to its demonstrated ability reversibly incorporate two lithium ions per redox center. As inserted into the nanosized particles within cathode, electrochemical reaction can be largely affected by interfacial chemistry at nanoparticle surface. We performed X-ray photoelectron spectroscopy using both soft (XPS) and hard (HAXPES) X-rays chemically distinguish depth-resolve...
CuF2 is an attractive multielectron cathode material that can store up to ∼528 mAh/g with a high operating voltage (∼3.55 V) and gravimetric energy density of (1874 Wh/kg). Unfortunately, the poor electrochemical reversibility has restricted its application primary batteries. Herein, we report key factors limiting through parallel investigation involving more reversible Cu0.5Fe0.5F2 compound. Our findings reveal intrinsic limitations come from diffusivity Cu ions, leading phase-separated...
In addressing the expensive transportation and disposal cost of waste activated sludge (WAS), an in situ reduction strategy was developed this study based on H2O2/O3 lysis a cryptic growth process. The critical roles solubilization biodegradability lysate were analyzed comprehensively. Under dosage 0.36 g O3/g mixed liquor volatile suspended solids (MLVSS), H2O2 addition (H2O2/O3 molar ratio 0.25) led to significant improvement cell performance terms MLVSS (35.2% vs 26.3%). Compared with O3...
Abstract Vanadyl phosphates comprise a class of multielectron cathode materials capable cycling two Li + , about 1.66 Na and some K ions per redox center. In this review, structures, thermodynamic stabilities, ion diffusion kinetics various A x VOPO 4 (A = Li, Na, K, NH ) polymorphs are discussed. Both the experimental data first‐principle calculations indicate kinetic limitations for alkali metal cycling, especially between 0 ≤ 1, metastability phases with > 1. This creates challenges...
The layered structure of molybdenum (oxy)pyrophosphate (δ-(MoO2)2P2O7) was synthesized by heating MoO2HPO4·H2O precursor at 560 °C. synthesis temperature selected using in situ high-temperature X-ray diffraction (XRD) depicting phase transformations the from room up to 800 Electrochemical evaluation reveals that four Li ions per formula unit can be intercalated into δ-(MoO2)2P2O7 upon discharge 2 V. Three voltage plateaus are observed 3.2, 2.6, and 2.1 V, lower than theoretical predictions....
Understanding the reaction mechanism of olivine compounds as electrode materials for lithium lithium‐ion batteries have has received much attention recently. The question whether LiFePO4 undergoes two‐phase or non‐nonequilibrium single‐phase during electrochemical processes taken center stage in understanding faster kinetics observed this material. Here, lithiation/delithiation Mg Mg‐substituted using high high‐resolution X‐ray diffraction(XRD), transmission electron microscopy(TEM), and...
Full, reversible intercalation of two Li+ has not yet been achieved in promising VOPO4 electrodes. A pronounced gradient reported the low voltage window (i.e., second lithium reaction) that is thought to originate from disrupted kinetics high regime first reaction). Here, we employ a combination hard and soft x–ray photoelectron absorption spectroscopy techniques depth profile solid state synthesized LiVOPO4 cycled within only. Analysis vanadium environment revealed no evidence gradient,...
Abstract All solid state lithium metal batteries (ASSLMBs) with enhanced energy density has driven the exploration of Li‐alloy anodes such as Li‐Mg alloy owing to its solid‐solution structure and high theoretical specific capacity. But Li atom diffusion limitation on electrode surface further leads sluggish atoms transport dynamics. Herein, single‐crystalline (110)‐oriented 0.9 Mg 0.1 (denoted LiMg(110)) anode is obtained by a tailored melt‐annealing procedure tackle above issues....
The structure of the novel compound Li3Mo4P5O24 has been solved from single crystal X-ray diffraction data. Mo cations in are present four distinct types MoO6 octahedra, each which one open vertex at corner participating a Mo═O double bond and whose other five corners shared with PO4 tetrahedra. On basis valence sum difference map (BVS-DM) analysis, this framework is predicted to support facile diffusion Li+ ions, hypothesis that confirmed by electrochemical testing data, show can be...