Kinetic Analysis of One-Step Solid-State Reaction for Li₄Ti₅O₁₂/C

Abstract

The kinetics of one-step solid-state reaction of Li(4)Ti(5)O(12)/C in a dynamic nitrogen atmosphere was first studied by means of thermogravimetric-differential thermal analysis technique at five different heating rates. According to the double equal-double steps method, the Li(4)Ti(5)O(12)/C solid-state reaction mechanism could be properly described as the Jander equation, which was a three-dimensional diffusion with spherical symmetry, and the reaction mechanism functions were listed as follows: f(α) = (3)/(2)(1 - α)(2/3)[1 - (1 - α)(1/3)](-1), G(α) = [1 - (1 - α)(1/3)](2). In FWO method, average activation energy, frequency factor, and reaction order were 284.40 kJ mol(-1), 2.51 × 10(18) min(-1), and 1.01, respectively. However, the corresponding values in FRL method were 271.70 kJ mol(-1), 1.00 × 10(17) min(-1), and 0.96, respectively. Moreover, the values of enthalpy of activation, Gibbs free energy of activation, and entropy of activation at the peak temperature were 272.06 kJ mol(-1), 240.16 kJ mol(-1), and 44.24 J mol(-1) K(-1), respectively.

Artificial Neural Networks for Pyrolysis, Thermal Analysis, and Thermokinetic Studies: The Status Quo

“…Additionally, the authors applied the developed neural network to the experimental data for Li 4 Ti 5 O 12 /C high-temperature reaction. The ANN output agrees well with the literature results [ 100 ] of these data analysis accomplished with isoconversional and model-fitting kinetic approaches. It is noteworthy that according to the isoconversional analysis, the activation energy of the process is more or less constant throughout the reaction, thus, indicating the single-step reaction kinetics.…”

Atomic Layer Fluorination of the Li4Ti5O12 Surface: A Multiprobing Survey

“…Different strategies have been used to overcome LTO drawbacks, essentially focusing on the kinetic limitations. Downsizing LTO particles and modifying their morphology increase the available exchange surface and improve the Li + insertion kinetics, − and coating LTO particles with a conductive carbonaceous layer, combined with nanostructuration, shows significant improvements. − The doping of the LTO structure by substituting either Li + /Ti 4+ cations (Mg 2+ , Ca 2+ , Zn 2+ , Cr 3+ , Al 3+ , La 3+ , Zr 4+ , V 5+ , Nb 5+ , Ta 5+ , Mo 6+ , etc.) or O 2– anions (Br – , N – , Cl – , or F – ) − is another strategy pursued to improve its electrochemical properties.…”

Kinetic analysis on the synthesis of Mg0.95Zn0.05TiO3 microwave dielectric ceramic by polymeric precursor method

“…They found that three dimensional diffusion model (D3) was the most probable mechanism function for the reaction. Hu et al [39] also investigated the kinetics of solid state reaction for Li 4 Ti 5 O 12 /C and observed Jander D3 as the most probable mechanism and the average value of activation energy for the system was 278 kJ/mol using FWO and FRL (Friedman-Reich-Levi) method. sintering method in the previous reports [6], which is most probably due to its low bulk density and porosity.…”