A5053499319- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advanced NMR Techniques and Applications
- Metal-Organic Frameworks: Synthesis and Applications
- Crystallography and molecular interactions
- Magnetism in coordination complexes
- Advanced Battery Technologies Research
- Extraction and Separation Processes
- Supramolecular Chemistry and Complexes
- Solid-state spectroscopy and crystallography
- Chemical Synthesis and Characterization
- Inorganic Chemistry and Materials
- Ferroelectric and Piezoelectric Materials
- Conducting polymers and applications
- Fuel Cells and Related Materials
- Supercapacitor Materials and Fabrication
- Advanced Memory and Neural Computing
- Magnetic and transport properties of perovskites and related materials
- Covalent Organic Framework Applications
- Magnetic Field Sensors Techniques
- NMR spectroscopy and applications
- Crystallography and Radiation Phenomena
- Magnetic Properties of Alloys
University of Cambridge
2020-2025
University of Windsor
2013-2024
The Faraday Institution
2021-2023
Florida State University
2020
Tallahassee Orthopedic Clinic
2020
Government of the Northern Territory
2001
Sodium filling inside hard carbon pores demonstrates increasingly metallic character with increasing pore size.
Abstract Increasing concerns regarding the sustainability of lithium sources, due to their limited availability and consequent expected price increase, have raised awareness importance developing alternative energy-storage candidates that can sustain ever-growing energy demand. Furthermore, limitations on transition metals used in manufacturing cathode materials, together with questionable mining practices, are driving development towards more sustainable elements. Given uniformly high...
Metal–organic framework nanoparticles (nanoMOFs) have been widely studied in biomedical applications. Although substantial efforts devoted to the development of biocompatible approaches, requirement tedious synthetic steps, toxic reagents, and limitations on shelf life solution are still significant barriers their translation clinical use. In this work, we propose a new postsynthetic modification nanoMOFs with phosphate-functionalized methoxy polyethylene glycol (mPEG–PO3) groups which, when...
The chemical and electrochemical reactions at the positive electrode-electrolyte interface in Li-ion batteries are hugely influential on cycle life safety. Ni-rich layered transition metal oxides exhibit higher interfacial reactivity than their lower Ni-content analogues, reacting via mechanisms that poorly understood. Here, we study pivotal role of electrolyte solvent, specifically cyclic ethylene carbonate (EC) linear ethyl methyl (EMC), determining charged LiNi0.33Mn0.33Co0.33O2 (NMC111)...
Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of dopant counterions. Here, we present a combined experimental theoretical study rebutting this belief. Using newly developed doping technique based on ion exchange, prepare highly doped films with several...
High-capacity Ni-rich layered metal oxide cathodes are highly desirable to increase the energy density of lithium-ion batteries. However, these materials suffer from poor cycling performance, which is exacerbated by increased cell voltage. We demonstrate here detrimental effect ethylene carbonate (EC), a core component in conventional electrolytes, when NMC811 (LiNi0.8Mn0.1Co0.1O2) charged above 4.4 V vs Li/Li+-the onset potential for lattice oxygen release. Oxygen loss enhanced...
Abstract Oxides with a face-centred cubic (fcc) anion sublattice are generally not considered as solid-state electrolytes the structural framework is thought to be unfavourable for lithium (Li) superionic conduction. Here we demonstrate Li conductivity in fcc-type oxides which face-sharing configurations have been created through cation over-stoichiometry rocksalt-type lattices via excess Li. We find that create novel spinel unconventional stoichiometry and raise energy of Li, thereby...
Metal–organic framework (MOF) materials have been prepared that contain a mechanically interlocked molecule (MIM) as the pillaring strut between two periodic Zn-carboxylate layers. The MIM linker is [2]rotaxane with [24]crown-6 (24C6) macrocycle and an aniline-based axle terminal pyridine donor groups. single-crystal X-ray structures of MOFs UWDM-2 (1,4-diazophenyl-dicarboxylate) UWDM-3 (1,4-biphenyl-dicarboxylate) show both frameworks are large enough to free volume required for rotation...
A series of metal–organic framework (MOF) materials has been prepared, each containing a mechanically interlocked molecule (MIM) as the linker and copper(II) paddlewheel secondary building unit (SBU). The MIM linkers are [2]rotaxanes with varying sizes crown ether macrocycles ([22]crown-6, 22C6; [24]crown-6, 24C6; [26]crown-6, 26C6; benzo[24]crown-6, B24C6) an anilinium-based axle four carboxylate donor groups. Herein, X-ray structures MOFs UWCM-1 (no crown) UWDM-1(22) compared demonstrate...
"Anode-free" batteries present a significant advantage due to their substantially higher energy density and ease of assembly in dry air atmosphere. However, issues involving lithium dendrite growth low cycling Coulombic efficiencies during operation remain be solved. Solid electrolyte interphase (SEI) formation on Cu its effect Li plating are studied here understand the interplay between current collector surface chemistry plated morphology. A native layer (N-SEI) was observed with...
The dynamic impacts from the ball mill process inducing a pressure phase change.
Sodium-ion batteries represent a promising alternative to lithium-ion systems. However, the rapid growth of sodium-ion battery technology requires sustainable and scalable synthetic route high-grade sodium hexafluorophosphate. This work demonstrates new multi-gram scale synthesis NaPF6 in which reaction ammonium hexafluorophosphate with metal THF solvent generates electrolyte salt absence impurities that are common commercial material. The high purity (absence insoluble NaF) allows for...
Abstract Sodium‐ion batteries (SIBs) are a promising grid‐level storage technology due to the abundance and low cost of sodium. The development new electrolytes for SIBs is imperative since it impacts battery life capacity. Currently, sodium hexafluorophosphate (NaPF 6 ) used as benchmark salt, but highly hygroscopic generates toxic HF. This work describes synthesis series borate salts, with electrochemical studies revealing that Na[B(hfip) 4 ]⋅DME (hfip=hexafluoroisopropyloxy, O i Pr F...
Transition metal dissolution is an important contributor to capacity fade in lithium-ion cells. NMR relaxation rates are proportional the concentration of paramagnetic species, making them suitable quantify dissolved transition metals battery electrolytes. In this work, 7Li, 31P, 19F, and 1H longitudinal transverse were measured study LiPF6 electrolyte solutions containing Ni2+, Mn2+, Co2+, or Cu2+ salts Mn from LiMn2O4. Sensitivities found vary by nuclide metal. 19F (PF6-) (solvent)...
A new mechanically interlocked molecular linker was prepared by using ring-closing metathesis (Grubbs I) to clip a [24]crown-6 ether wheel around an axle containing both Y-shaped diphenylimidazole and isophthalic acid groups. metal-organic framework (MOF) material this ZnII ions. Single-crystal X-ray diffraction experiments showed that the MOF contains imidazolium-based rotaxane linked dimeric [Zn2 (NO3 )(DEF)] secondary building units (SBUs). Variable-temperature (VT), 2 H solid-state NMR...
We present the rapid and robust acquisition of 103 Rh solid-state NMR spectra for a series inorganic organometallic compounds. Relativistic DFT calculations provide relationships between chemical shift tensors, structure, bonding.
A series of transition-metal organometallic complexes with commonly occurring metal-chlorine bonding motifs were characterized using (35)Cl solid-state NMR (SSNMR) spectroscopy, nuclear quadrupole resonance (NQR) and first-principles density functional theory (DFT) calculations interaction tensors. Static ultra-wideline spectra acquired in a piecewise manner at standard (9.4 T) high (21.1 magnetic field strengths the WURST-QCPMG pulse sequence. The electric gradient (EFG) chemical shielding...
Chlorine ligands in a variety of diamagnetic transition-metal (TM) complexes common structural motifs were studied using (35)Cl solid-state NMR (SSNMR), and insight into the origin observed parameters was gained through first-principles density functional theory (DFT) calculations. The WURST-CPMG pulse sequence variable-offset cumulative spectrum (VOCS) methods used to acquire static SSNMR powder patterns at both standard (9.4 T) ultrahigh (21.1 magnetic field strengths, with latter...
NaNiO2 (NNO) has been investigated as a promising sodium-ion battery (NIB) cathode material, but it is limited by degradation-induced capacity fade. On desodiation, NNO forms multiple phases with large superstructures due in part to Na+-ion vacancy ordering, however, their structures are unknown. Here, we report structural solution the Na2/3NiO2 (P/3) de-sodiated phase using combined Rietveld refinement of high-resolution synchrotron X-ray (SXRD) and neutron diffraction (NPD) data, magnetic...
NaNiO2 (NNO) has been investigated as a promising sodium-ion battery cathode material, but it is limited by degradation-induced capacity fade. On desodiation, NNO forms multiple phases with large superstructures due in part to Na+-ion vacancy ordering; however, their structures are unknown. Here, we report structural solution the Na2/3NiO2 (P'3) desodiated phase using combined Rietveld refinement of high-resolution synchrotron X-ray (SXRD) and neutron powder diffraction (NPD) data, magnetic...
Phosphorus‐doped carbons provide a balance between the electrochemical stability of graphitic lattices and high energy density phosphorus materials when used in lithium sodium‐ion batteries. Herein, comprehensive ex situ 31 P, 7 Li, 23 Na solid‐state nuclear magnetic resonance analysis intercalation mechanism novel, stable, dual‐phase phosphorus‐doped, phosphorus‐encapsulated turbostratic graphite microspheres is presented. Results indicate that occurs through formation Li 3 P from white...
The properties of different NaPF 6 electrolyte concentrations have been studied, finding 1 M in EC:DEC gives the highest bulk conductivity. However, sodium-ion cells, lower gave similar cycling performance.