Synthesis, non-isothermal kinetic and thermodynamic studies of the formation of LiMnPO4 from NH4MnPO4·H2O precursor

Solid State Reaction Mechanisms of the LiMnPO4 Formation Using Special Function and Thermodynamic Studies

“…8,9,18 The nonisothermal (isoconversional) kinetic model is a model-free method, which involves measuring temperatures (T) corresponding to the fixed value of extent of conversion (α) at different heating rates (β, β = (dT/dt)/°C min −1 , t is time/min). The α-values from thermogravimetric analysis may be defined as the ratio of actual mass loss to the total mass loss corresponding to the investigated process:…”

“…5,6 Besides, the higher operating voltage is also well within the typical electrolyte stability window. 7 In the previous works, 8,9 the lithium singleand binary-metals of LiM II PO 4 (M II = Mn, Mg, Mn 0.5 Mg 0.5 , and Co 0.5 Mg 0.5 ) were synthesized via their hydrate precursors (NH 4 M II PO 4 ·H 2 O) and compared between two different Li sources of LiOH·H 2 O and Li 2 CO 3 and found that Li 2 CO 3 exhibited smaller particle size. In addition, the nonisothermal kinetic triplets including activation energy E α , pre-exponential factor A, and the reaction mechanism functions f(α) or g(α) from the formation processes of LiMnPO 4 from NH 4 MnPO 4 · H 2 O precursor were studied and reported using Ozawa− Flynn−Wall (OFW), Kissinger−Akahira−Sunose (KAS), Coat−Redfern, and multiple heating scan rates methods.…”

“…In addition, the nonisothermal kinetic triplets including activation energy E α , pre-exponential factor A, and the reaction mechanism functions f(α) or g(α) from the formation processes of LiMnPO 4 from NH 4 MnPO 4 · H 2 O precursor were studied and reported using Ozawa− Flynn−Wall (OFW), Kissinger−Akahira−Sunose (KAS), Coat−Redfern, and multiple heating scan rates methods. 8,9 The related thermodynamic functions (ΔH ‡, ΔS ‡, and ΔG ‡) of the transition state complexes are also evaluated and reported. Our recent work 10 reported the isoconversional kinetics, reaction model, and thermodynamic studies of NH 4 Co 0.8 Zn 0.1 Mn 0.1 PO 4 ·H 2 O using the iterative method of KAS equation to determine the exact E α values.…”

Wet Mechanical Route To Synthesize Morphology-Controlled NH4MnPO4·H2O and Its Conversion Reaction into LiMnPO4

“…The reaction with lithium sources at high temperatures leads to the formation of impurity phases. 11 The SS-LMP powder in this study also contained tiny amounts of Mn 2 O 3 as a byproduct, whereas HT-LMP was phase pure. The Rietveld analysis was carried out for all phases except the impurity phase.…”

Synthesis and properties of LiM II PO 4 (M II = Mg, Mn 0.5 Mg 0.5 , Co 0.5 Mg 0.5 ) affected by isodivalent doping and Li-sources

“…Recently, the synthesized NH 4 MnPO 4 $H 2 O precursor was reported to be converted to LiMnPO 4 by the solid state reaction with the different Li-sources of Li 2 CO 3 or LiOH$H 2 O. In addition, the kinetic and thermodynamic properties of the solid state reaction between the synthesized NH 4 MnPO 4 $H 2 O and Li 2 CO 3 were studied by OFW and KAS including the iterative methods [27]. The solid state reaction product was confirmed to be LiMnPO 4 with the crystal sizes of 200e400 nm.…”