Influence of Cation Substitution on Cycling Stability and Fe-Cation Migration in LiFeMTeO (M = Al, In) Cathode Materials.

LiFeTeO adopts a crystal structure, described in space group , related to that of LiSbO, in which Te, Fe, and Li cations reside in a partially ordered configuration within an hcp array of oxide ions. Chemical or electrochemical insertion of lithium is accompanied by a fully reversible migration of some of the Fe cations with an initial capacity of 120 mA h g (2.85 Li per formula unit).

Anion-polarisation-directed short-range-order in antiperovskite LiFeSO.

Short-range ordering in cation-disordered cathodes can have a significant effect on their electrochemical properties. Here, we characterise the cation short-range order in the antiperovskite cathode material LiFeSO, using density functional theory, Monte Carlo simulations, and synchrotron X-ray pair-distribution-function data. We predict partial short-range cation-ordering, characterised by favourable OLiFe oxygen coordination with a preference for polar -OLiFe over non-polar -OLiFe configurations.

Direct Observation of Dynamic Lithium Diffusion Behavior in Nickel-Rich, LiNiMnCoO (NMC811) Cathodes Using Muon Spectroscopy.

Ni-rich layered oxide cathode materials such as LiNiMnCoO (NMC811) are widely tipped as the next-generation cathodes for lithium-ion batteries. The NMC class offers high capacities but suffers an irreversible first cycle capacity loss, a result of slow Li diffusion kinetics at a low state of charge. Understanding the origin of these kinetic hindrances to Li mobility inside the cathode is vital to negate the first cycle capacity loss in future materials design.

In Situ Diffusion Measurements of a NASICON-Structured All-Solid-State Battery Using Muon Spin Relaxation.

In situ muon spin relaxation is demonstrated as an emerging technique that can provide a volume-averaged local probe of the ionic diffusion processes occurring within electrochemical energy storage devices as a function of state of charge. Herein, we present work on the conceptually interesting NASICON-type all-solid-state battery LiM(PO), using M = Ti in the cathode, M = Zr in the electrolyte, and a Li metal anode. The pristine materials are studied individually and found to possess low ionic hopping activation energies of ∼50-60 meV and competitive Li self-diffusion coefficients of ∼10-10 cm s at 336 K.

Secondary Structural Changes in Proteins as a Result of Electroadsorption at Aqueous-Organogel Interfaces.

The electroadsorption of proteins at aqueous-organic interfaces offers the possibility to examine protein structural rearrangements upon interaction with lipophilic phases, without modifying the bulk protein or relying on a solid support. The aqueous-organic interface has already provided a simple means of electrochemical protein detection, often involving adsorption and ion complexation; however, little is yet known about the protein structure at these electrified interfaces. This work focuses on the interaction between proteins and an electrified aqueous-organic interface via controlled protein electroadsorption.

Electrodeposition of Gold Nanostructures at the Interface of a Pickering Emulsion.

The controlled electrodeposition of nanoparticles at the surface of an emulsion droplet offers enticing possibilities in regards to the formation of intricate structures or fine control over the locus or duration of nanoparticle growth. In this work we develop electrochemical control over the spontaneous reduction of aqueous phase Au(III) by heterogeneous electron transfer from decamethylferrocene present in an emulsion droplet - resulting in the growth of nanoparticles. As gold is a highly effective conduit for the passage of electrical current, even on the nanoscale, the deposition significantly enhances the current response for the single electron transfer of decamethylferrocene when acting as a redox indicator.

Electrochemical Insight into the Brust-Schiffrin Synthesis of Au Nanoparticles.

The mechanism of the Brust-Schiffrin gold nanoparticle synthesis has been investigated through the use of ion transfer voltammetry at the water/1,2-dichloroethane (DCE) solution interface, combined with X-ray absorption fine structure (XAFS) of the reaction between [AuCl4](-) and thiol (RSH) in homogeneous toluene (TL) solution. Ion transfer calculations indicate the formation of [AuCl2](-) at RSH/Au ratios from 0.2-2 with a time-dependent variation observed over several days.

Visible-Light-Mediated Generation of Nitrogen-Centered Radicals: Metal-Free Hydroimination and Iminohydroxylation Cyclization Reactions.

The formation and use of iminyl radicals in novel and divergent hydroimination and iminohydroxylation cyclization reactions has been accomplished through the design of a new class of reactive O-aryl oximes. Owing to their low reduction potentials, the inexpensive organic dye eosin Y could be used as the photocatalyst of the organocatalytic hydroimination reaction. Furthermore, reaction conditions for a unique iminohydroxylation were identified; visible-light-mediated electron transfer from novel electron donor-acceptor complexes of the oximes and Et3N was proposed as a key step of this process.

Metal deposition at the liquid-liquid interface.

Metal nanoparticles are readily formed, with a reasonable degree of size and shape control, using solution-based reduction methods under ambient conditions. Despite the large number of reports in this field, much of our knowledge of nanoparticle growth is largely empirical, with the relationship between particle form and growth conditions, for example, still not well understood. Many nanoparticle preparation routes actually depend on not one, but two, solution phases, i.

Electrochemical modulation of SERS at the liquid/liquid interface.

A surface enhanced Raman scattering system to detect silver nanoparticle adsorption at the water|1,2-dichlorobenzene interface is reported. The Raman response as a function of distance on either side of the interface reveals a reproducible spatial variation, which is potential dependent for a number of adsorption and desorption cycles.