Computer modelling techniques have been used to examine the mechanistic features of oxygen ion transport in La8Sr2Si6O26 and La9.33Si6O26 apatite-oxides at atomic level. The potential model reproduces observed complex structures both phases, which are comprised [SiO4] tetrahedral units La/O channels. Defect simulations examined lowest energy interstitial vacancy sites. results suggest that migration is via a mechanism with direct linear path between O5 Interstitial predicted for...

Atomistic simulations have allowed us to gain fresh insight into the mechanisms of oxygen ion transport in novel apatite silicates, which form part a new family ionic conductors for potential fuel cell applications.

Apatite-type silicates have been attracting considerable interest as a new class of oxide ion conductor, whose conduction is mediated by interstitial ions. We report here the first 29Si solid state NMR studies these materials with systematic investigation thirteen compositions. Our results indicate correlation between silicon environment and observed conductivity. Specifically, samples which show poor conductivity demonstrate single resonance, whereas fast conducting compositions more...

Computer simulation techniques have been used to investigate the defect chemistry of perovskite-structured ionic conductors based upon AZrO(3)(A = Ca, Ba) and LaMO(3)(M Sc, Ga). Our studies examined dopant site-selectivity, oxide ion migration dopant-defect association at atomic level. The energetics incorporation in AZrO(3) show strong correlation with size. We predict Y(3+) be one most favourable dopants for BaZrO(3) on energetic grounds, which accords experimental work where this cation...

The development of active hydrogen oxidation reaction (HOR) and oxygen reduction (ORR) catalysts for use in anion exchange membrane fuel cells (AEMFCs), which are free from platinum group metals (PGMs), is expected to bring this technology one step closer commercial applications. This paper reports our recent progress developing HOR Pt-free PGM-free (Pd/CeO2 NiCo/C, respectively), ORR Co3O4 AEMFCs. were prepared by different synthesis techniques characterized both physical-chemical...

Abstract Aqueous zinc–air batteries (ZABs) are a low‐cost, safe, and sustainable technology for stationary energy storage. ZABs with pH‐buffered near‐neutral electrolytes have the potential longer lifetime compared to traditional alkaline due slower absorption of carbonates at nonalkaline pH values. However, existing often contain halide salts, which corrosive threaten precipitation ZnO as dominant discharge product. This paper presents method designing halide‐free aqueous ZAB using...

Silicon kerf waste from a photovoltaic silicon production process is assessed as an anode material for application lithium ion battery anode. In contrast to previous studies, the Si-kerf used as-produced, with no chemical treatment or physical processing beyond solvent PEG removal. The as-produced performed well as, better than, previously reported anodes and found outperform cleaned sample blade sawing larger particle size. This highlights advantage of diamond wire cutting process, which...

The apatite-type phases, La(9.33+x)(Si/Ge)(6)O(26+3x/2), have recently been attracting considerable interest as potential electrolytes for solid oxide fuel cells. In this paper we report results from a range of doping studies in the Si based systems, aimed at determining key features required optimisation conductivities. Systems examined included alkaline earth on rare site, and P, B, Ga, V site. By suitable strategies, factors such level cation vacancies oxygen excess investigated. show...

Abstract Novel apatite‐type silicates are attracting considerable interest as a new family of oxide‐ion conductors with potential use in fuel cells and ceramic membranes. Combined computer modeling X‐ray absorption (EXAFS) techniques have been used to gain fresh insight, at the atomic level, into site selectivity local structures wide range dopants these apatite materials. The results indicate that an unusually broad dopant ions (in terms size charge state) can substitute for La 9.33 Si 6 O...

The anisotropic thermal and chemical expansion of rhombohedral (R3̅c) La1–xSrxMnO3+δ (x = 0.2, 0.3) was investigated by in situ high temperature X-ray diffraction submicrometer size powders pure oxygen nitrogen (inert) atmospheres. the long axis c found to be close twice as short a. large c-axis is caused rectification antiferrodistortive tilting decompression MnO6/2 octahedra. unit cell parameters were shown strongly dependent on partial pressure oxygen, which attributed...

Transition metal oxides with ramsdellite and spinel structures have been the subject of considerable investigation as candidate electrode materials for lithium‐ion batteries. Good ionic conductivity has reported , shown to exhibit good electrochemical properties a Li‐anode material. We recently demonstrated that series displays complete range solubility at high temperatures between compositions these phases can be preserved room temperature by quenching. In this study we report on members...

Despite the technological importance of hard and soft PZT, Pb(Zr,Ti)O3, ceramics, mechanisms ferroelectric hardening softening remain widely discussed in literature. The phenomena have traditionally been investigated relation with dielectric manifestations such as aging susceptibility constriction polarization-electric field hysteresis loop. Here, we present a systematic investigation ferroelastic properties PZT both tetragonal rhombohedral phases. A particular focus has devoted to domain...

Abstract The ionic liquid (IL)‐based electrolyte comprising 1.2 M lithium bis(fluorosulfonyl)imide (LiFSI) in N‐propyl‐N‐methylpyrrolidinium (PYR 13 FSI) (ILE) has been evaluated as a suitable system for the high‐voltage cathode material LiNi 0.5− x Mn 1.5+ O 4 (LNMO) when cycled vs. graphite anodes. oxidative stability of ILE was by linear sweep voltammetry (LSV) and synthetic charge‐discharge profile (SCPV) found to exceed that state‐of‐the‐art 1 LiPF 6 : ethylene carbonate (EC)...

In this paper, detailed studies of the effect Mg doping in apatite-type oxide ion conductor La9.33Si6O26 are reported. is confirmed as an ambisite dopant, capable substituting for both La and Si, depending on starting composition. A large enhancement conductivity observed Si site substitution, with a reduction substitution site. Neutron powder diffraction show that agreement cation size expectations, enlargement unit cell corresponding increase tetrahedral sites. For site, contraction...

Here we report on molten salt synthesis of four different compounds in the K2O–Na2O–Nb2O5 system. The three K4Nb6O17, K2Nb4O11 and KNb3O8, with non-cubic crystal structures, were prepared as single crystalline particles large aspect ratios. K4Nb6O17 was a plate-like morphology, fibre-like finally KNb3O8 had plate like morphology. KxNa1−xNbO3, cubic perovskite structure at conditions, only obtained cube-shaped crystals, which became larger increasing temperature. A systematic study influence...

This paper presents a novel modelling and experimental investigation of aqueous near-neutral chloride electrolytes for rechargeable zinc–air batteries.

Zinc-air batteries (ZABs) offer a sustainable and safe pathway to low-cost energy storage. Recent research shows that thermally-sintered porous Zn electrodes with three-dimensional network structure can enhance the performance lifetime of ZABs, but they are expensive energy-intensive manufacture. In this work, monolithic fabricated through an efficient cold sintering process (CSP) were studied for rechargeable ZABs. Electrochemical studies extended charge-discharge cycling show good...

Solid electrolytes in Li-ion batteries offer enhanced safety and stability contribute to improved energy density. In this study, a novel approach synthesize solid molecular ionic composite as an electrolyte for using 1-benzyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [(Bn)mim][TFSI] liquid the principal component, rigid polymer poly(2,2'-disulfonyl-4,4'-benzidine terephthalamide) (PBDT), LiTFSI salt was explored. The composition of membrane systematically varied, with percentage...