Materials Science NMR
Mere Anarchy is Loosed: Structural Disorder in Cu2Zn1–xCdxSnS4
Amit Bhattacharya – @AmitB0021
Solid-state NMR spectroscopy is used to delve into the local structural variation in photovoltaic Cu2Zn1–xCdxSnS4 materials and their conversion to a stannite phase upon critical Cd-loading. 113Cd NMR spectroscopy reveals the coexistence of stannite and kesterite. 63Cu NMR data combined with DFT computations resolve the conundrum of Cu/Zn disorder.
Paramagnetic ss-NMR applied to copper complexes derived from pyridine/imidazole compounds
Ayelen Florencia Crespi – @AyeCrespi
The presence of an unpaired electron in paramagnetic molecules generates significant effects in NMR spectra. The combination of DFT calculations, X-ray crystallography and EPR with ss-NMR can provide a solution to the structural study of paramagnetic systems. Here, different families of copper complexes were analyzed employing experimental and theoretical tools.
Novel Sampling Schemes for the Indirect Detection of Ultrawideline 195Pt Solid-State NMR Spectra for the Characterization of Heterogeneous Catalysts
Benjamin Atterberry – @BenjaminAtterb1
The noble metal platinum is widely utilized in numerous catalytic processes. However, the structure of Pt sites in heterogeneous catalysts are often ill-defined. Herein, we introduce a series of solid-state NMR experiments that use indirect detection of a sensitive spy nucleus (1H or 31P) to rapidly acquire 195Pt NMR spectra.
Case study of a protein-based biopolymer using solid-state NMR
Bhargy Sharma – @BhargySharma
In our research, we study a protein-based biopolymer - the slime from velvet worms. This slime has unique physico-chemical properties which can inspire novel recyclable sustainable materials. Combining bioinformatics and biophysical tools, we propose the mechanism of structural transitions from viscous crude slime solution to fibers with high tensile stiffness.
NMRTools.jl: a simple, open source interface for NMR data in Julia
Chris Waudby – @chris_waudby
Julia is a modern language optimised for scientific computation. To facilitate the use of Julia by the NMR community, here we introduce NMRTools.jl, an open source package providing an interface to import and visualise NMR data. Interested users are welcomed to contribute to the development of this ongoing project.
2D EXSY NMR and molecular dynamics (MD) simulations of anions of an RTIL (BMIM+-TFSI-)
Jinlei Cui – @cui_jinlei
2D EXSY NMR and molecular dynamics (MD) simulations are applied to investigate the diffusivity of anions of an RTIL (BMIM+–TFSI–), dissolved in five different organic solvents, in the micropores of activated carbon. The comparisons of ion diffusivities between the experiments and the MD simulations suggest the need to consider also the surface functionalities of activated carbon for the simulation of ion diffusion in the micropores of activated carbon.
Local structure of dopants in metal halide perovskites
Dominik Kubicki – @DominikJKubicki
Doping with metals, non-metals, and small organic molecules is essential for enhancing the optoelectronic properties of metal halide perovskites. Those dopants are typically present in only very small quantities, so it is challenging to study them. I will show how solid-state MAS NMR can help.
New Methods targetting Battery Material Characterization
Isha Yadav – @IshaYadav_1809
Battery is efficient and safer energy storage device . We will use advanced NMR instrumentation and pulse sequence (19 F – 7 Li correlation ) to study solid polymer electrolytes to establish ion conductivity – structural relationship , stability- structural relationship and through DNP we can deal with electrode-electrolyte interface.
Electrochemical Complexation of Polyatomic Aluminum Ions to Heterogeneous Organic Electrode Samples Investigated Using Solid-State Dipolar-Mediated NMR Methods
Leo W. Gordon – @Leowgordon
Rechargeable aluminum-organic batteries consist of Earth-abundant materials with tunable properties. However, due to the complexity of these systems there is no complete, experimentally validated mechanism in the literature. We employ solid-state NMR methodologies to investigate the electrochemical enolization mechanism of quinones, while also elucidating the nature of their electroactive ions.
Characterization of phosphorus clusters via multiple quantum solid state NMR
Lokeswara Rao Potnuru – @lokeswarnmr
Nonclassical growth pathways are generally confined to analysis via microscopy and X-Ray techniques due to prenucleation cluster size and stability constraints. Herein, we describe a novel technique for analyzing prenucleation cluster formation via 31P NMR spin counting of vitrified samples, which allows for atomic systems to be analyzed at varying time points.
Solid-state 31P NMR study of Ca/Mg modified biochars aiming application as slow-release phosphate fertilisers
Mariana Coelho Santoro – @marianacsantoro
This work describes a solid-state 31P NMR investigation of the chemical nature of adsorbed phosphate groups in Ca/Mg modified biochars. Biomass was used to synthesise steam-activated biochars, followed by precipitation of Ca or Mg metals for later adsorption of phosphates from phosphate-rich solutions, aiming the obtention of a material with bioavailable phosphate forms to be used as slow-release fertilisers. The 31P NMR results showed that the Mg/modified biochars had a higher phosphate adsorption capacity. Also, signals with distinct chemical shifts and linewidths were observed in the spectra of samples immersed in different phosphate solutions.
NMR insights into the impact of Al incorporation on the structure and dynamics of β-Li3PS4
Hongtao Qu – @QuHongtao
We investigate the impact of Al incorporation on the structure and dynamics of Al-doped lithium thiophosphates (Li3-3xAlxPS4) based on β-Li3PS4. 27Al and 6Li MAS NMR spectra confirm that Al3+ ions occupy octahedral sites in the structure. Quantitative analyses of 27Al NMR that the maximum Al incorporation is x=0.06 in Li3-3xAlxPS4. NMR relaxometry shows that the activation barrier for long-range Li ion diffusion in β-Li3PS4 hardly changes upon Al incorporation, but the onset temperature for doping comes down significantly. The activation barrier in the subsequently formed multiphase material decreases significantly, however, indicating a different more efficient Li ion conduction pathways.
Towards Endogeneous DNP-NMR in semiconducting nanoparticles
Ran Eitan Abutbul – @RanEitanAbutbul
This work demonstrates the endogenous DNP approach in nanoparticles where the polarizing agents are transition metal ions with unpaired electrons incorporated in the inorganic lattice. CdS:Mn nanoparticles were synthesized and characterized using TEM, EPR, and ICP-MS. Significant DNP enhancement for 113Cd nuclei surface and core moieties was observed.
Probing the atomic-level structure of LiPON amorphous electrolytes of microbatteries using solid-state NMR
Racha Bayzou – @RBayzou
Amorphous LiPON thin-films are the standard electrolytes for all-solid microbatteries. They are prepared by the radiofrequency sputtering from Li3PO4 targets under a pure N2 atmosphere. In this work, we elucidate the relationships between deposition conditions and local atomic-level structure using 31P, 7Li and 14N solid-state NMR.
Resonance with a cause: applying NMR and NQR spectroscopy to inorganic metal bromides
Riley W. Hooper – @rileyhooper97
Halogen NMR and NQR spectroscopy is often challenging due to large quadrupole moments for the NMR-active nuclei of Cl, Br, and I. Nevertheless, these nuclei can provide invaluable structural and dynamic information for materials. We have studied two such examples of lead-bromide materials via 79/81Br NMR and NQR spectroscopy.
Overhauser Dynamic Nuclear Polarization to study local water dynamics in polymer solution
Thomas Webber – @ThomasW35463255
Overhauser Dynamic Nuclear Polarization (ODNP) is a novel magnetic resonance tool which combines NMR and EPR to study local (within 1 nm) water dynamics near spin-labeled surfaces. I apply ODNP to study water diffusion in aqueous polymer systems, showing that polymer crowding slows molecular water significantly.
Understanding the interfacial region in organic ionic composite materials
Yady Senayda Garcia Castillo – @yadygarcia89
Composites between OIPCs and polymer particles have recently been of interest because they combine the non-flammability, non-volatility, plasticity, electrochemical, and thermal stability of OIPCs, while at the same offering the mechanical stability provided by the polymer. ssNMR is implemented to study the structural changes and ions dynamics and is correlated with Electrochemical Impedance Spectroscopy (EIS) to determine the ion transport in the composite. It is expected that the composite will take advantage of the intrinsic properties of the OIPC like plasticity, the mechanical strength of the polymer, and the formation of the interphase between them, which will add new properties.
Revealing the Dehydration/Deuteration Processes at the Liquid-Solid Interface by Nuclear Magnetic Resonance Spectroscopy
Chuanyu Yan – @yan_chuanyu
The liquid-solid interface is of great importance in fundamental and applied research. However, the in-situ characterization of liquid-solid interfaces is very challenging. In this work, we demonstrated that {1H–29Si-}1H multiple-contact cross polarization with indirect detection (MCPi) solid-state nuclear magnetic resonance (ssNMR) spectroscopy is an excellent tool for studying dehydration and deuterium exchange at the solvent-silica interface.