Operando Optical Imaging Platforms to Study Li Diffusion in the Solid State Battery Reactions

Elementary reaction modeling of CO2/H2O co-electrolysis cell considering effects of cathode thickness

Enhancing the diffusion of lithium ions to propel sulfur redox for lithium-sulfur batteries

The diffusion of lithium on a Ru(001) surface has been studied with nuclear magnetic resonance techniques using the radioactive isotope ${}^{8}\mathrm{Li}$ as a probe. As a function of substrate temperature and alkali metal coverage the nuclear spin-lattice relaxation measurements show the existence of two distinctly different diffusion barriers on the surface, valued at 0.46 and 0.22 eV. The former is attributed to jumps from step to terrace sites, whereas the latter is the barrier between adjacent terrace sites. At 200 K the Li diffusion was observed from low to full coverage.

Diffusion of lithium (Li) in uniformly gallium (Ga)-doped monocrystalline bulk zinc oxide (ZnO) is studied over a wide temperature range (500–1150°C) and is demonstrated to be dictated by the distribution of Ga. Below 800°C, the indiffusion of Li from a Li-doped ZnO sputtered film into n+ single crystalline ZnO yields an abrupt and compensated Li-doped box region with the Li concentration matching the free-electron concentration, in accordance with several previous experimental and theoretical reports. However, experimental observations of Li-diffusion at higher temperatures reveal a dissociative diffusion mechanism for heat treatments up to 1150°C. By employing a reaction-diffusion model that includes both Li and Ga, a dissociation energy of 4.6 eV is obtained from the experimental Li diffusion data. This is in excellent agreement with theoretical results for the dissociation of (LiZnGaZn)0 (4.8 eV) into Lii+ and (GaZnVZn)− and suggests that this neutral and stable acceptor-donor pair prevails in Li- and Ga-doped ZnO.

Lithium diffusion in graphene and graphite: Effect of edge morphology

Ab initio investigation of the surface properties of Cu(111) and Li diffusion in Cu thin film

Particle growth by the heterogeneous reaction of aldehydes was evaluated in 0.5 m3 Teflon film bags under darkness in the presence of background seed aerosols. The aldehydes used were as follows: glyoxal, butanal, hexanal, octanal, and decanal. To study acid catalyst effects on aldehyde heterogeneous reactions, one of the Teflon bags was initially filled with seed aerosols composed of ammonium sulfate-aerosol acidified with sulfuric acid. These results were compared to particle growth reactions that contained only ammonium sulfate as a background seed aerosol. The gas-phase aldehydes were then added to the Teflon bags. In selected experiments, 1-decanol was also added to the Teflon bags with aldehydes to clarify particle growth via a heterogeneous hemiacetal/acetal formation in the presence/absence of an acid catalyst. The particle size distribution and growth were measured using a scanning mobility particle sizer (TSI-SMPS), and the results were applied to predicting aerosol growth and size distribution changes by condensation and heterogeneous reactions. Aerosols created from the heterogeneous reactions of aldehydes were collected directly on an ungreased zinc selenide (ZnSe) FTIR disk (25 mm in diameter) by impaction. The ZnSe disks were directly analyzed for product functional groups inthe aerosol phase using a Fourier transform infrared (FTIR) spectrometer with a deuterated triglycine sulfate (DTGS) detector. Aerosol growth by heterogeneous aldehyde reactions proceeds via a hydration, polymerization process, and hemiacetal/acetal formation from the reaction of aldehydes with alcohols. These aldehyde heterogeneous reactions were accelerated in the presence of an acid catalyst, H2SO4, and led to higher aerosol yields than when H2SO4 was not present in the seed aerosol. The FTIR spectra obtained from the growing aerosol, also illustrated aldehyde group transformation in the particle phase as a function of the heterogeneous reaction. It was concluded that aldehydes, which can be produced by atmospheric photochemical reactions, can significantly contribute on secondary aerosol formation through heterogeneous reactions in the presence of an acid catalyst.

Mechanochemical approach to get layered double hydroxides: Mechanism explore on crystallite growth

Reactive single-solute liquid chromatography in fully porous fixed-bed columns involves complex transport and chemical reaction processes occurring simultaneously in both the liquid and solid phases. This work presents a comprehensive analytical-numerical framework based on a linear general rate model that incorporates key transport mechanisms including axial dispersion, external film diffusion, intraparticle pore diffusion, and interfacial mass transfer coupled with first-order homogeneous reactions in the liquid phase and heterogeneous reactions on the solid adsorbent. A key novelty of this study is to investigate how homogeneous and heterogeneous reactions influence concentration fronts during linear chromatographic processes and the hybrid analytical numerical framework that solves the coupled transport-reaction equations in the Laplace domain, followed by a numerical inversion to capture time-resolved concentration profiles. Analysis of elution curves under varying kinetic and transport conditions shows that increasing both homogeneous and heterogeneous reaction rates enhances separation efficiency and reactor performance. The model’s predictions are validated against a high-resolution finite-volume scheme and benchmarked with existing models, demonstrating superior accuracy and reliability. These results highlight the proposed methodology as a valuable tool for optimizing the design and operation of reactive chromatographic systems.

Heterogeneous reaction processes in metal combustion

In this study, nanostructured Ni75Mg16.66Y8.34 (at%) catalyst powder was prepared using two methods. In method one, the pure elemental powders were subjected to high energy ball milling for 5 to 25 h with a ball to powder weight ratio of 20. In method two, the pure elemental powders were pressed, heat treated at 800°C for 8 h (solid state reaction); then, they were ball milled for 2, 7.5 and 10 h, similarly to the first method. Finally, morphology, phases, particle size, crystallite size, and lattice strain values of the prepared powder alloys were determined by X-ray diffraction (XRD) and scanning electron microscope (SEM) methods. The XRD patterns showed that the Mg2Ni9Y ternary intermetallic phase was not formed in the sample prepared by method one; however, that was formed in the samples prepared by the second method. The required milling time for preparing the samples with the same powder specifications by method two was about 50% less than the time required by method one. It was found that the Ni75Mg16.66Y8.34 (at%) powder with smaller particle size, smaller crystallite size, and higher lattice strain values could be prepared by combining solid state reaction and mechanical milling processes.

High-purity synthesis of La2SiO5 by solid-state reaction between La2O3 and different characteristics of SiO2

Crystal structure and lithium electrochemical extraction properties of olivine type LiFePO 4

In anode free batteries (AFBs), the current collector acts as anode simultaneously and has large volume expansion which is generally considered as a negative effect decreasing the structural stability of a battery. Moreover, despite many studies on the fast lithium diffusion in the current collector materials of AFB such as copper and aluminum, the involved Li diffusion mechanism in these materials remains poorly understood. Through first-principles calculation and stress-assisted diffusion equations, here we study the Li diffusion mechanism in several current collectors and related alloys and clarify the effect of volume expansion on Li diffusion respectively. It is suggested that due to the lower Li migration barriers in aluminum and tin, they should be more suitable to be used as AFB anodes, compared to copper, silver, and lead. The Li diffusion facilitation in copper with a certain number of vacancies is proposed to explain why the use of copper with a thickness ⩽ 100 nm as the protective coating on the anode improves the lifetime of the batteries. We show that the volume expansion has a positive effect on Li diffusion via mechanical–electrochemical coupling. Namely, the volume expansion caused by Li diffusion will further induce stress which in turn affects the diffusion. These findings not only provide in-depth insight into the operating principle of AFBs, but also open a new route toward design of improved anode through utilizing the positive effect of mechanical–electrochemical coupling.

Chemical imaging and diffusion of hydrogen and lithium in lithium aluminate