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Optimisation of the annealing time for the fabrication of nitrogen-doped graphitic-spheres (NDGSs), formed from a nitrogen-functionalised aromatic precursor at 800 °C, to give high nitrogen doping has been performed. Thorough analysis of the NDGSs, approximately 3 μm in diameter, pinpointed an optimum annealing time of 6 to 12 hours to obtain highest nitrogen content at the surface of the spheres (reaching a stoichiometry of around C3N at the surface and C9N in the bulk), with the quantity of sp2 and sp3 surface nitrogen varying with annealing time. The results suggest that changes in the nitrogen dopant level occur through slow diffusion of the nitrogen throughout the NDGSs, along with reabsorption of nitrogen-based gases produced during annealing. A stable bulk nitrogen dopant level of 9% was revealed in the spheres. The NDGSs performed well as anodes in lithium-ion batteries, providing a capacity of up to 265 mA h g-1 at a charging rate of C/20, but did not perform well in sodium-ion batteries without the use of diglyme, consistent with the presence of graphitic regions, but with low internal porosity.

Transition metal dissolution is an important contributor to capacity fade in lithium-ion cells. NMR relaxation rates are proportional to the concentration of paramagnetic species, making them suitable to quantify dissolved transition metals in battery electrolytes. In this work, 7Li, 31P, 19F, and 1H longitudinal and transverse relaxation rates were measured to study LiPF6 electrolyte solutions containing Ni2+, Mn2+, Co2+, or Cu2+ salts and Mn dissolved from LiMn2O4. Sensitivities were found to vary by nuclide and by transition metal. 19F (PF6-) and 1H (solvent) measurements were more sensitive than 7Li and 31P measurements due to the higher likelihood that the observed species are in closer proximity to the metal center. Mn2+ induced the greatest relaxation enhancement, yielding a limit of detection of ∼0.005 mM for 19F and 1H measurements. Relaxometric analysis of a sample containing Mn dissolved from LiMn2O4 at ∼20 °C showed good sensitivity and accuracy (suggesting dissolution of Mn2+), but analysis of a sample stored at 60 °C showed that the relaxometric quantification is less accurate for heat-degraded LiPF6 electrolytes. This is attributed to degradation processes causing changes to the metal solvation shell (changing the fractions of PF6-, EC, and EMC coordinated to Mn2+), such that calibration measurements performed with pristine electrolyte solutions are not applicable to degraded solutions-a potential complication for efforts to quantify metal dissolution during operando NMR studies of batteries employing widely-used LiPF6 electrolytes. Ex situ nondestructive quantification of transition metals in lithium-ion battery electrolytes is shown to be possible by NMR relaxometry; further, the method's sensitivity to the metal solvation shell also suggests potential use in assessing the coordination spheres of dissolved transition metals.

A series of triarylamines was synthesised and screened for their suitability as catholytes in redox flow batteries using cyclic voltammetry (CV). Tris(4-aminophenyl)amine was found to be the strongest candidate. Solubility and initial electrochemical performance were promising; however, polymerisation was observed during electrochemical cycling leading to rapid capacity fade prescribed to a loss of accessible active material and the limitation of ion transport processes within the cell. A mixed electrolyte system of H3 PO4 and HCl was found to inhibit polymerisation producing oligomers that consumed less active material reducing rates of degradation in the redox flow battery. Under these conditions Coulombic efficiency improved by over 4 %, the maximum number of cycles more than quadrupled and an additional theoretical capacity of 20 % was accessed. This paper is, to our knowledge, the first example of triarylamines as catholytes in all-aqueous redox flow batteries and emphasises the impact supporting electrolytes can have on electrochemical performance.

Sodium-ion batteries represent a promising alternative to lithium-ion systems. However, the rapid growth of sodium-ion battery technology requires a sustainable and scalable synthetic route to high-grade sodium hexafluorophosphate. This work demonstrates a new multi-gram scale synthesis of NaPF6 in which the reaction of ammonium hexafluorophosphate with sodium metal in THF solvent generates the electrolyte salt with the absence of the impurities that are common in commercial material. The high purity of the electrolyte (absence of insoluble NaF) allows for concentrations up to 3 M to be obtained accurately in binary carbonate battery solvent. Electrochemical characterization shows that the degradation dynamics of sodium metal-electrolyte interface are different for more concentrated (>2 M) electrolytes, suggesting that the higher concentration regime (above the conventional 1 M concentration) may be beneficial to battery performance.

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 the detrimental effect of ethylene carbonate (EC), a core component in conventional electrolytes, when NMC811 (LiNi0.8Mn0.1Co0.1O2) is charged above 4.4 V vs. Li/Li+ – the onset potential for lattice oxygen release. Oxygen loss is enhanced by EC-containing electrolytes – compared to EC-free – and correlates with more electrolyte oxidation/breakdown and cathode surface degradation, which increase concurrently above 4.4 V. In contrast, NMC111 (LiNi0.33Mn0.33Co0.33O2), which does not release oxygen up to 4.6 V, shows similar extents of degradation irrespective of the electrolyte. This work highlights the incompatibility between conventional EC-based electrolytes and Ni-rich cathodes (more generally, cathodes that release lattice oxygen such as Li-/Mn-rich and disordered rocksalt cathodes), and motivates further work on wider classes of electrolytes and additives., The present research has been supported by the Faraday Institution degradation project (FIRG001) and EPSRC (EP/S003053/1). W. M. D., M. F. L. D., and C. P. G. acknowledge funding from Cambridge Royce facilities grant EP/P024947/1 and Sir Henry Royce Institute grant EP/R00661X/1. The authors are grateful to A. Jansen, S.E. Trask, B.J. Polzin, and A.R. Dunlop at the U.S. Department of Energy’s CAMP (Cell Analysis, Modeling, and Prototyping) Facility, Argonne National Laboratory, for producing and supplying the electrodes in this work. We thank Nigel Howard for assistance with the ICP-OES measurements, and Bernardine Rinkel and Jennifer Allen for useful discussions.

Sodium‐ion batteries (SIBs) are a promising grid‐level storage technology due to the abundance and low cost of sodium. The development of new electrolytes for SIBs is imperative since it impacts battery life and capacity. Currently, sodium hexafluorophosphate (NaPF6) is used as the benchmark salt, but is highly hygroscopic and generates toxic HF. This work describes the synthesis of a series of sodium borate salts, with electrochemical studies revealing that Na[B(hfip)4]⋅DME (hfip=hexafluoroisopropyloxy, OiPrF) and Na[B(pp)2] (pp=perfluorinated pinacolato, O2C2(CF3)4) have excellent electrochemical performance. The [B(pp)2]− anion also exhibits a high tolerance to air and water. Both electrolytes give more stable electrode‐electrolyte interfaces than conventionally used NaPF6, as demonstrated by impedance spectroscopy and cyclic voltammetry. Furthermore, they give greater cycling stability and comparable capacity to NaPF6 for SIBs, as shown in commercial pouch cells.

Summary An H-shaped [2]rotaxane with a biphenyl axle and a 24-crown-8 (24C8) macrocycle was inserted into the tetrahedral cavities of the isostructural fcu MOFs PCN-57, UiO-68-d4, and UWCM-10. The resulting rotaxane containing MOFs UWDM-8, UWDM-9-d4, and UWDM-10 have precise spatial arrangements of two different mobile components—a rigid rotor (tetramethylphenyl, phenyl-d4, or tetrazine) and a rotaxane macrocycle (24C8). The mobility of these units was characterized by variable-temperature (VT) solid-state nuclear magnetic resonance (SSNMR). VT 13C SSNMR showed that the translational position of the macrocyclic wheel along the [2]rotaxane axle is dictated by the bulk and rotational orientation of the central rotor, while VT 2H SSNMR demonstrated that the dynamics of the rotor are influenced by the presence of the macrocycle.

Zr(iv) metal-organic frameworks (MOFs) UiO-68 and PCN-57, containing triphenylene dicarboxylate (TPDC) and tetramethyl-triphenylene dicarboxylate (TTDC) linkers, respectively, were doped with an H-shaped tetracarboxylate linker that contains a [2]rotaxane molecular shuttle. The new MOFs, UWDM-8 and UWDM-9, contain a [2]rotaxane crossbar spanning the tetrahedral cavities of the fcu topology while the octahedral cavities remain empty. 13C solid-state NMR (SSNMR) spectra and solution 1H NMR spectra verified that the [2]rotaxanes were included as designed. Variable-temperature (VT) cross polarization (CP) magic-angle spinning (MAS) 13C SSNMR was used to explore the translational motion of the macrocyclic ring in both MOFs. The SSNMR results clearly show that the structure of the linker (TPDCvs.TTDC) affects the shuttling rate of the macrocyclic ring, although questions remain as to how rotation of the central phenylene unit of the strut might also affect the motion of the macrocycle.

An H-shaped [2]rotaxane comprising a bis(benzimidazole) axle and a 24-membered crown ether wheel appended with four trityl groups forms a highly crystalline material with enough free volume to allow large amplitude motion of the interlocked macrocycle. Variable-temperature (VT) 2H solid-state nuclear magnetic resonance (SSNMR) was used to characterize the dynamics of the [2]rotaxane wheel in this material.

The concept of “robust dynamics” describes the incorporation of mechanically interlocked molecules (MIMs) into metal-organic framework (MOF) materials such that large amplitude motions (e.g., rotation or translation of a macrocycle) can occur inside the free volume pore of the MOF. To aid in the preparation of such materials, reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF NOTT-101. New linkers were synthesized that have a T-shape, based on a triphenylene tetra-carboxylate strut, and their incorporation into Cu(II)-based MOFs was investigated. The single-crystal structures of three new MOFs, UWCM-12 (fof), β-UWCM-13 (loz), UWCM-14 (lil), with naked T-shaped linkers were determined; β-UWCM-13 is the first reported example of the loz topology. A fourth MOF, UWDM-14 (lil) is analogous to UWCM-14 (lil) but contains a [2]rotaxane linker. Variable-temperature, 2H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.

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 the dopant counterions. Here, we present a combined experimental and theoretical study rebutting this belief. Using a newly developed doping technique based on ion exchange, we prepare highly doped films with several counterions of varying size and shape and characterize their carrier density, electrical conductivity, and paracrystalline disorder. In this uniquely large data set composed of several classes of high-mobility conjugated polymers, each doped with at least five different ions, we find electrical conductivity to be strongly correlated with paracrystalline disorder but poorly correlated with ionic size, suggesting that Coulomb traps do not limit transport. A general model for interacting electrons in highly doped polymers is proposed and carefully parametrized against atomistic calculations, enabling the calculation of electrical conductivity within the framework of transient localization theory. Theoretical calculations are in excellent agreement with experimental data, providing insights into the disorder-limited nature of charge transport and suggesting new strategies to further improve conductivities.

We demonstrate the combined use of NMR-enhanced crystallography and solvent-free synthesis by accelerated aging (AA), for the discovery and structural characterization of a novel cadmium-based open metal–organic framework (MOF) belonging to the class of zeolitic imidazolate frameworks (ZIFs). Although solid-state NMR spectroscopy has been used to assist in structural characterization of crystalline solids by powder X-ray diffraction (PXRD), typically through quantification of the contents of the asymmetric unit, this work highlights how it can take a more active role in guiding structure determination, by elucidating the coordination environment of the metal node in a novel MOFs. Exploration of AA reactions of cadmium oxide (CdO) and 2-methylimidazole (HMeIm) enabled the synthesis of not only the previously reported yqt1-topology framework but also a new material (1) exhibiting a Cd/MeIm ratio of 1:3, contrasting the 1:2 ratio expected for a ZIF. Structural characterization of 1 was enabled by using 111Cd solid-state nuclear magnetic resonance (SSNMR) to provide information on the coordination environment of the cadmium node. Specifically, 111Cd SSNMR experiments were conducted on a series of model compounds to correlate the cadmium coordination environment to the observed isotropic chemical shift, δiso(111Cd), followed by multinuclear SSNMR experiments on 1 to determine the nature of the metal coordination environment and the number of distinct chemical sites. This information was used in refinement of the molecular level structure from the available PXRD data, a technique termed NMR-enhanced crystallography, revealing that 1 is an open diamondoid (dia) topology Cd(MeIm)2 framework based on Cd2+ ions tetrahedrally coordinated with MeIm– ligands and additional HMeIm guest molecules within the framework pores. Although AA was initially devised as a clean, mild route for making MOFs, these results provide a proof-of-principle of how, by combining it with SSNMR spectroscopy as a means to overcome limitations of PXRD structure determination, it can be used to screen for new solid phases in the absence of solvents, high temperatures, or mechanical impact that are inherent to other thermally-, solution-, or mechanochemically-based techniques.

Hard carbons have shown considerable promise as anodes for emerging sodium-ion battery technologies. Current understanding of sodium-storage behaviour in hard carbons attributes capacity to filling of graphitic interlayers and pores, and adsorption at defects, although there is still considerable debate regarding the voltages at which these mechanisms occur. Here, ex situ23Na solid-state NMR and total scattering studies on a systematically tuned series of hard carbons revealed the formation of increasingly metallic sodium clusters in direct correlation to the growing pore size, occurring only in samples which exhibited a low voltage plateau. Combining experimental results with DFT calculations, we propose a revised mechanistic model in which sodium ions store first simultaneously and continuously at defects, within interlayers and on pore surfaces. Once these higher energy binding sites are filled, pore filling occurs during the plateau region, where the densely confined sodium takes on a greater degree of metallicity.

The chemical and electrochemical reactions at the positive electrode–electrolyte interface in Li-ion batteries are hugely influential on cycle life and safety. Ni-rich layered transition metal oxides exhibit higher interfacial reactivity than their lower Ni-content analogues, reacting via mechanisms that are poorly understood. Here, we study the pivotal role of the electrolyte solvent, specifically cyclic ethylene carbonate (EC) and linear ethyl methyl carbonate (EMC), in determining the interfacial reactivity at charged LiNi0.33Mn0.33Co0.33O2(NMC111) and LiNi0.8Mn0.1Co0.1O2(NMC811) cathodes by using both single-solvent model electrolytes and the mixed solvents used in commercial cells. While NMC111 exhibits similar parasitic currents with EC-containing and EC-free electrolytes during high voltage holds in NMC/Li4Ti5O12(LTO) cells, this is not the case for NMC811. Online gas analysis reveals that the solvent-dependent reactivity for Ni-rich cathodes is related to the extent of lattice oxygen release and accompanying electrolyte decomposition, which is higher for EC-containing than EC-free electrolytes. Combined findings from electrochemical impedance spectroscopy (EIS), TEM, solution NMR, ICP, and XPS reveal that the electrolyte solvent has a profound impact on the degradation of the Ni-rich cathode and the electrolyte. Higher lattice oxygen release with EC-containing electrolytes is coupled with higher cathode interfacial impedance, a thicker oxygen-deficient rock-salt surface reconstruction layer, more electrolyte solvent and salt breakdown, and higher amounts of transition metal dissolution. These processes are suppressed in the EC-free electrolyte, highlighting the incompatibility between Ni-rich cathodes and conventional electrolyte solvents. Finally, new mechanistic insights into the chemical oxidation pathways of electrolyte solvents and, critically, the knock-on chemical and electrochemical reactions that further degrade the electrolyte and electrodes curtailing battery lifetime are provided.

Metal-organic framework nanoparticles (nanoMOFs) have been widely studied in biomedical applications. Although substantial efforts have been devoted to the development of biocompatible approaches, the requirement of tedious synthetic steps, toxic reagents, and limitations on the shelf life of nanoparticles in solution are still significant barriers to their translation to clinical use. In this work, we propose a new postsynthetic modification of nanoMOFs with phosphate-functionalized methoxy polyethylene glycol (mPEG-PO3) groups which, when combined with lyophilization, leads to the formation of redispersible solid materials. This approach can serve as a facile and general formulation method for the storage of bare or drug-loaded nanoMOFs. The obtained PEGylated nanoMOFs show stable hydrodynamic diameters, improved colloidal stability, and delayed drug-release kinetics compared to their parent nanoMOFs. Ex situ characterization and computational studies reveal that PEGylation of PCN-222 proceeds in a two-step fashion. Most importantly, the lyophilized, PEGylated nanoMOFs can be completely redispersed in water, avoiding common aggregation issues that have limited the use of MOFs in the biomedical field to the wet form-a critical limitation for their translation to clinical use as these materials can now be stored as dried samples. The in vitro performance of the addition of mPEG-PO3 was confirmed by the improved intracellular stability and delayed drug-release capability, including lower cytotoxicity compared with that of the bare nanoMOFs. Furthermore, z-stack confocal microscopy images reveal the colocalization of bare and PEGylated nanoMOFs. This research highlights a facile PEGylation method with mPEG-PO3, providing new insights into the design of promising nanocarriers for drug delivery.

Funder: Blavatnik Family Foundation, "Anode-free" batteries present a significant advantage due to their substantially higher energy density and ease of assembly in a dry air atmosphere. However, issues involving lithium dendrite growth and low cycling Coulombic efficiencies during operation remain to be solved. Solid electrolyte interphase (SEI) formation on Cu and its effect on Li plating are studied here to understand the interplay between the Cu current collector surface chemistry and plated Li morphology. A native interphase layer (N-SEI) on the Cu current collector was observed with solid-state nuclear magnetic resonance spectroscopy (ssNMR) and electrochemical impedance spectroscopy (EIS). Cyclic voltammetry (CV) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) studies showed that the nature of the N-SEI is affected by the copper interface composition. An X-ray photoelectron spectroscopy (XPS) study identified a relationship between the applied voltage and SEI composition. In addition to the typical SEI components, the SEI contains copper oxides (Cu x O) and their reduction reaction products. Parasitic electrochemical reactions were observed via in situ NMR measurements of Li plating efficiency. Scanning electron microscopy (SEM) studies revealed a correlation between the morphology of the plated Li and the SEI homogeneity, current density, and rest time in the electrolyte before plating. Via ToF-SIMS, we found that the preferential plating of Li on Cu is governed by the distribution of ionically conducting rather than electronic conducting compounds. The results together suggest strategies for mitigating dendrite formation by current collector pretreatment and controlled SEI formation during the first battery charge.

The global drive towards decarbonisation means there is increasing need for large-scale energy storage, which has focussed research efforts into sodium-ion batteries (SIBs).1 SIBs are well suited to grid-storage applications due to the wide abundance, even distribution and low cost of sodium deposits.2 This contrasts to the better known and understood lithium-ion batteries (LIBs), where lithium is much less abundant. Additionally, the use of sodium has other sustainability implications, which are desirable for grid-scale applications, as it allows cobalt-free cathodes to be used and the copper current collectors at the anode to be replaced by aluminium. Currently SIBs use NaPF6 as the chosen electrolyte salt,3 however commercial supplies of this are often of low-grade and contain NaF (a hydrolysis product of NaPF6), making it unsuitable for battery use.4 Alternatively, pre-made electrolyte solutions of NaPF6 may be purchased, but the cost can be prohibitive and limits solvent exploration. Herein, this talk will detail the synthesis of high-grade NaPF6 from the addition of NH4PF6 with sodium metal in THF solvent. By performing the reaction under anhydrous conditions, NaPF6 can be prepared in the absence of hydrolysis products (NaF), as confirmed by solid-state NMR spectroscopy and powder X-ray diffraction. With high-grade NaPF6 in hand, we have looked at the effects of using higher concentration electrolyte solutions of NaPF6 (>1 M) in ethylene carbonate:diethyl carbonate (EC:DEC 1:1 v/v) solvent. This showed the degradation dynamics of sodium metal-electrolyte interface are different for more concentrated (>1 M) electrolytes, although there is a trade-off with bulk conductivity compared to 1 M solutions. Lastly, the performance of the synthesized NaPF6 has been tested in commercial 2- and 3-electrode pouch cells by Faradion Ltd, UK.5 References: 1 D. Kundu, E. Talaie, V. Duffort and L. F. Nazar, Angew. Chem. Int. Ed., 2015, 54, 3431–3448. 2 C. Vaalma, D. Buchholz, M. Weil and S. Passerini, Nat. Rev. Mater., 2018, 3, 18013. 3 A. Ponrouch, D. Monti, A. Boschin, B. Steen, P. Johansson and M. R. Palacín, J. Mater. Chem. A, 2015, 3, 22–42. 4 A. Bhide, J. Hofmann, A. Katharina Dürr, J. Janek and P. Adelhelm, Phys. Chem. Chem. Phys., 2014, 16, 1987–1998. 5 D. M. C. Ould, S. Menkin, C. A. O'Keefe, F. Coowar, J. Barker, Clare P. Grey and D. S. Wright, Angew. Chem. Int. Ed., 2021, 60, 24882–24887. Figure 1

Zinc(II) metal–organic framework (MOF) materials were prepared using a porphyrin-based tetracarboxylate linker and pyridine-terminated [2]rotaxane linkers as pillars. Two pillaring rotaxanes (R = H...

Tapia-Ruiz, Nuria et al., Increasing concerns regarding the sustainability of lithium sources, due to their limited availability and consequent expected price increase, have raised awareness of the importance of developing alternative energy-storage candidates that can sustain the ever-growing energy demand. Furthermore, limitations on the availability of the transition metals used in the manufacturing of cathode materials, together with questionable mining practices, are driving development towards more sustainable elements. Given the uniformly high abundance and cost-effectiveness of sodium, as well as its very suitable redox potential (close to that of lithium), sodium-ion battery technology offers tremendous potential to be a counterpart to lithium-ion batteries (LIBs) in different application scenarios, such as stationary energy storage and low-cost vehicles. This potential is reflected by the major investments that are being made by industry in a wide variety of markets and in diverse material combinations. Despite the associated advantages of being a drop-in replacement for LIBs, there are remarkable differences in the physicochemical properties between sodium and lithium that give rise to different behaviours, for example, different coordination preferences in compounds, desolvation energies, or solubility of the solid–electrolyte interphase inorganic salt components. This demands a more detailed study of the underlying physical and chemical processes occurring in sodium-ion batteries and allows great scope for groundbreaking advances in the field, from lab-scale to scale-up. This roadmap provides an extensive review by experts in academia and industry of the current state of the art in 2021 and the different research directions and strategies currently underway to improve the performance of sodium-ion batteries. The aim is to provide an opinion with respect to the current challenges and opportunities, from the fundamental properties to the practical applications of this technology., The authors gratefully acknowledge RS2E and Alistore-ERI for funding their research into Na-ion batteries. The funding received from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 646433 (NAIADES), the Swedish Research Council, the Swedish Energy Agency (#37671-1), and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS), are all gratefully acknowledged. The many fruitful discussions within ALISTORE-ERI, and especially with M Rosa Palacín, have been most valuable. P J is also grateful for the continuous support from several of the Chalmers Areas of Advance: Materials Science and Energy. Funding from the European Union’s innovation program H2020 is acknowledged: H2020-MSCA-COFUND-2016 (DOC-FAM, Grant Agreement No. 754397). A Ponrouch is grateful to the Spanish Ministry for Economy, Industry and Competitiveness Severo Ochoa Programme for Centres of Excellence in R&D (SEV-2015-0496).

This study compares the efficacy and tolerability of olanzapine versus risperidone among patients with schizophrenia who are established in outpatient psychiatric care and entering supported employment. A multicenter, randomized, double-blind trial was conducted among 107 outpatients with schizophrenia, who were cross-titrated to flexible dose risperidone or olanzapine over 2 weeks. Clinical endpoints included time to hospitalization and persistence on assigned medication. Weight, laboratory tests, psychopathology, neurologic side effects, social adjustment and role functioning were assessed at 3-6 month intervals. Data were analyzed first by randomized treatment, and then reassessed controlling for prior medication treatment. The proportion of patients on assigned medication at 18 months was 30.9% for risperidone and 37.3% for olanzapine. Mean doses were 6.4±3.2mg daily for risperidone, and 17.0±5.0mg daily for olanzapine. The groups did not differ significantly in time to medication discontinuation, first hospitalization or first employment. There were few differences in psychopathology, laboratory, or neurological assessments between groups at 18 months. Patients randomized to olanzapine gained modestly more weight. Controlling for pre-randomization medication suggested improvement in some aspects of psychopathology from switching medications; however, switching from olanzapine to risperidone was associated with more hospitalizations. Risperidone and olanzapine have similar efficacy and tolerability in patients with schizophrenia who are participating in supported employment. Randomization to olanzapine was associated with more weight gain, but randomization from olanzapine to risperidone appeared to be associated with a greater likelihood of hospitalization. Careful monitoring of metabolic effects and participation in supported employment may have contributed to minimal weight gain and metabolic effects.

One of the key challenges facing Li-ion batteries with Ni-rich layered cathodes is the poor interfacial stability at both electrodes. Several recent reports have investigated the reactivity of the electrolyte at the surface of LiNixMnyCo1-x-yO2 (NMC) as a function of Ni content and electrolyte composition,1,2 but many of the complex processes taking place are not fully understood. In this work, we use a rapid electrochemical-based screening protocol3 to quantify the anodic stability of single-solvent electrolytes and additive-containing electrolyte solutions with respect to the fraction of Ni in the NMC cathode. The current that flows during a high voltage hold at 4.6 V vs Li/Li+ is found to be sensitive to the NMC surface chemistry, the degree of delithiation, and the composition of the electrolyte. Post-test XPS, solution NMR, and online electrochemical mass spectroscopy (OEMS) are combined to study the electrode- and electrolyte-dependent degradation products that are insoluble on the surface of the electrode, soluble in the electrolyte, and released as gas. The insights from quantification of the electrolyte anodic stability and the degradation signatures identified through this work highlight the importance of developing unique solutions to lower the interfacial reactivity of Ni-rich cathodes, which is a critical step to prolong the cycle life of high-energy Li-ion batteries. References Y. Zhang, Y. Katayama, R. Tatara, L. Giordano, Y. Yu, D. Fraggedakis, J. G. Sun, F. Maglia, R. Jung, M. Z. Bazant, Y. Shao-Horn, Energy Environ. Sci., 13, 183, 2020. J. Wandt, A. T. S. Freiberg, A. Ogrodnik, H. A. Gasteiger, Mater. Today, 21, 825, 2018. A. Tornheim, S. E. Trask, Z. Zhang, J. Electrochem. Soc., 163, A1717, 2016.

NMR-enhanced crystallography enables the characterization of a novel cadmium-based, open metal-organic framework (MOF) from a solvent-free "accelerated aging" process. Whereas accelerated aging was devised as a clean, mild route for making MOFs, these results highlight how it application in materials discovery and characterization is aided by a combination of X-ray diffraction and solid-state NMR spectroscopy.

Correction for ‘A revised mechanistic model for sodium insertion in hard carbons’ by Heather Au et al., Energy Environ. Sci., 2020, 13, 3469–3479, DOI: 10.1039/D0EE01363C.

‘Anode-free’ batteries present a significant advantage due to their substantially higher energy density and ease of assembly in a dry air atmosphere. However, potential safety issues due to lithium (Li) dendrite growth rather than smooth Li metal plating on the Cu current collector, and low cycling coulombic efficiency during their operation are delaying their practical implementation. To understand the interplay between Cu surface chemistry and the morphology of the plated Li, we studied the SEI formation on Cu and the preferential plating of Li using ssNMR, insitu NMR, XPS, ToF-SIMS, SEM and EIS. A native interphase layer (N-SEI) is formed instantaneously on copper current collectors upon their immersion in LiPF6-based electrolyte. The nature of the N-SEI is affected by the copper interface composition, homogeneity and formation time. In addition to the typical SEI components, it contains CuxO and its reaction products. Parasitic semi-reversible electrochemical reactions were observed with in-situ NMR measurements of Li plating efficiency during the first five cycles. The morphology of the plated lithium is affected by the SEI homogeneity, current density and rest time in the electrolyte before the plating. The preferential plating of Li is governed by the distribution of ionic conducting compounds rather than electronic conducting compounds.[i] [i] Menkin, Svetlana; O'Keefe, Christopher A.; Gunnarsdottir, Anna B.; Dey, Sunita; Pesci, Federico; Shen, Zonghao; et al. (2020): Towards an Understanding of the SEI Formation and Lithium Preferential Plating on Copper. ChemRxiv. Preprint. https://doi.org/10.26434/chemrxiv.12839792.v1

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. A metal-organic framework (MOF) material was prepared using this linker and ZnII ions. Single-crystal X-ray diffraction experiments showed that the MOF contains an imidazolium-based rotaxane linked by dimeric [Zn2 (NO3 )(DEF)] secondary building units (SBUs). Variable-temperature (VT), 2 H solid-state NMR spectroscopy was used to characterize the motion of the "soft" wheel component around the rigid "hard" lattice of the framework. At higher temperatures (above 150 °C), it was demonstrated that the 24-membered, macrocyclic ring of the MOF undergoes rapid, thermally driven rotation about the axle inside the voids of the lattice.

Large-scale population analyses coupled with advances in technology have demonstrated that the human genome is more diverse than originally thought. To date, this diversity has largely been uncovered using short-read whole-genome sequencing. However, these short-read approaches fail to give a complete picture of a genome. They struggle to identify structural events, cannot access repetitive regions, and fail to resolve the human genome into haplotypes. Here, we describe an approach that retains long range information while maintaining the advantages of short reads. Starting from ∼1 ng of high molecular weight DNA, we produce barcoded short-read libraries. Novel informatic approaches allow for the barcoded short reads to be associated with their original long molecules producing a novel data type known as “Linked-Reads”. This approach allows for simultaneous detection of small and large variants from a single library. In this manuscript, we show the advantages of Linked-Reads over standard short-read approaches for reference-based analysis. Linked-Reads allow mapping to 38 Mb of sequence not accessible to short reads, adding sequence in 423 difficult-to-sequence genes including disease-relevant genes STRC, SMN1, and SMN2. Both Linked-Read whole-genome and whole-exome sequencing identify complex structural variations, including balanced events and single exon deletions and duplications. Further, Linked-Reads extend the region of high-confidence calls by 68.9 Mb. The data presented here show that Linked-Reads provide a scalable approach for comprehensive genome analysis that is not possible using short reads alone.

A series of transition-metal organometallic complexes with commonly occurring metal-chlorine bonding motifs were characterized using 35Cl solid-state NMR (SSNMR) spectroscopy, 35Cl nuclear quadrupole resonance (NQR) spectroscopy, and first-principles density functional theory (DFT) calculations of NMR interaction tensors. Static 35Cl ultra-wideline NMR spectra were acquired in a piecewise manner at standard (9.4 T) and high (21.1 T) magnetic field strengths using the WURST-QCPMG pulse sequence. The 35Cl electric field gradient (EFG) and chemical shielding (CS) tensor parameters were readily extracted from analytical simulations of the spectra; in particular, the quadrupolar parameters are shown to be very sensitive to structural differences, and can easily differentiate between chlorine atoms in bridging and terminal bonding environments. 35Cl NQR spectra were acquired for many of the complexes, which aided in resolving structurally similar, yet crystallographically distinct and magnetically inequivalent chlorine sites, and with the interpretation and assignment of 35Cl SSNMR spectra. 35Cl EFG tensors obtained from first-principles DFT calculations are consistently in good agreement with experiment, highlighting the importance of using a combined approach of theoretical and experimental methods for structural characterization. Finally, a preliminary example of a 35Cl SSNMR spectrum of a transition-metal species (TiCl4) diluted and supported on non-porous silica is presented. The combination of 35Cl SSNMR and 35Cl NQR spectroscopy and DFT calculations is shown to be a promising and simple methodology for the characterization of all manner of chlorine-containing transition-metal complexes, in pure, impure bulk and supported forms. Fast and furious: A series of transition-metal organometallic complexes with commonly occurring metal-chlorine bonding motifs were characterized using a combination of 35Cl solid-state NMR (SSNMR) spectroscopy, 35Cl nuclear quadrupole resonance (NQR) spectroscopy and first-principles density functional theory (DFT) calculations. Static 35Cl ultra-wideline NMR spectra were rapidly acquired in a piecewise manner at high magnetic field strengths. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A series of metal-organic framework (MOF) materials has been prepared, each containing a mechanically interlocked molecule (MIM) as the linker and a copper(II) paddlewheel as the secondary building unit (SBU). The MIM linkers are [2]rotaxanes with varying sizes of crown ether macrocycles ([22]crown-6, 22C6; [24]crown-6, 24C6; [26]crown-6, 26C6; benzo[24]crown-6, B24C6) and an anilinium-based axle containing four carboxylate donor groups. Herein, the X-ray structures of MOFs UWCM-1 (no crown) and UWDM-1(22) are compared and demonstrate the effect of including a macrocycle around the axle of the linker. The rotaxane linkers are linear and result in nbo-type MOFs with void space that allows for motion of the interlocked macrocycle inside the MOF pores, while the macrocycle-free linker is bent and yields a MOF with a novel 12-connected bcc structure. Variable temperature (2)H solid-state nuclear magnetic resonance showed that the macrocycles in UWDM-1(22), UWDM-1(24), and UWDM-1(B24) undergo different degrees and rates of rotation depending on the size and shape of the macrocycle.

Chlorine ligands in a variety of diamagnetic transition-metal (TM) complexes in common structural motifs were studied using (35)Cl solid-state NMR (SSNMR), and insight into the origin of the observed (35)Cl NMR parameters was gained through first-principles density functional theory (DFT) calculations. The WURST-CPMG pulse sequence and the variable-offset cumulative spectrum (VOCS) methods were used to acquire static (35)Cl SSNMR powder patterns at both standard (9.4 T) and ultrahigh (21.1 T) magnetic field strengths, with the latter affording higher signal-to-noise ratios (S/N) and reduced experimental times (i.e.,1 h). Analytical simulations were performed to extract the (35)Cl electric field gradient (EFG) tensor and chemical shift (CS) tensor parameters. It was found that the chlorine ligands in various bonding environments (i.e., bridging, terminal-axial, and terminal-equatorial) have drastically different (35)Cl EFG tensor parameters, suggesting that (35)Cl SSNMR is ideal for characterizing chlorine ligands in TM complexes. A detailed localized molecular orbital (LMO) analysis was completed for NbCl5. It was found that the contributions of individual molecular orbitals must be considered to fully explain the observed EFG parameters, thereby negating simple arguments based on comparison of bond lengths and angles. Finally, we discuss the application of (35)Cl SSNMR for the structural characterization of WCl6 that has been grafted onto a silica support material. The resulting tungsten-chloride surface species is shown to be structurally distinct from the parent compound.

Chlorine ligands in a variety of diamagnetic transition-metal (TM) complexes in common structural motifs were studied using 35Cl solid-state NMR (SSNMR), and insight into the origin of the observed 35Cl NMR parameters was gained through first-principles density functional theory (DFT) calculations. The WURST-CPMG pulse sequence and the variable-offset cumulative spectrum (VOCS) methods were used to acquire static 35Cl SSNMR powder patterns at both standard (9.4 T) and ultrahigh (21.1 T) magnetic field strengths, with the latter affording higher signal-to-noise ratios (S/N) and reduced experimental times (i.e.

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 a [2]rotaxane with a [24]crown-6 (24C6) macrocycle and an aniline-based axle with terminal pyridine donor groups. The single-crystal X-ray structures of MOFs UWDM-2 (1,4-diazophenyl-dicarboxylate) and UWDM-3 (1,4-biphenyl-dicarboxylate) show that both frameworks are large enough to contain the free volume required for rotation of the interlocked 24C6 macrocycle, but the frameworks are interpenetrated (UWDM-2, three-fold, and UWDM-3, two-fold). In particular, for UWDM-3 the 24C6 rings of the pillaring MIM are positioned directly inside the square openings of neighboring zinc dicarboxylate layers. Variable-temperature (VT) (2)H SSNMR demonstrated that the 24C6 macrocycles in UWDM-2 and UWDM-3 can only undergo restricted motions related to ring flexibility or partial rotation but are incapable of undergoing free rotation. VT-powder X-ray diffraction studies showed that upon activation of UWDM-3, by removing solvent, a phase change occurs. The new β-phase of UWDM-3 retained crystallinity, and (2)H SSNMR demonstrated that the 24C6 macrocyclic ring of the pillared MIM strut is now free enough to undergo full rotation. Most importantly, the phase change is reversible; the β version of the MOF can be reverted to the original α state by resolvation, thus demonstrating, for the first time, that the dynamics of a MIM inside a solid material can be controlled by a reversible phase change.