Comparison of the microwave-induced combustion and solid-state reaction for the synthesis of LiMn2O4 powder and their electrochemical properties

EDTA as chelating agent for sol-gel synthesis of spinel LiMn2O4 cathode material for lithium batteries

“…Considering the products with similar particle size, it has been currently demonstrated that LiMn 2 O 4 with good crystallinity must be prepared at T>600 °C. For example, Jin et al [1] obtained well-shaped octahedral LMO grains by a two-step synthesis at 700 °C; Zhao et al [3] prepared LMO at 750 °C using a sol-gel method assisted by citric acid; calcination at 600 °C for 5h achieved nanocrystalline LMO (≈80 nm) prepared by combustion method [4]; LMO nanoparticles (165 nm average size) were obtained by precipitation method and sintering at 800 °C for 10 h [50]; nanocrystalline LMO particles were prepared by an ultrasonic spray pyrolysis method using nitrate salts at 800 °C in air atmosphere [5]; the solid-state combustion method requested a calcination at 800 °C for 10 h to obtain grain size ≈100 nm; well-crystallized LMO synthesized by cellulose-citric acid method was sintered at 750-900 °C for 10 h [46]; a combustion method using urea as a fuel was developed to grow LMO at T≈500 °C [62]; submicronic LMO powders were prepared using a methanolic solution of metal acetates and succinic acid with sintering at 800 °C [63]; microwave-heated LMO powders were prepared at 800 °C by Fu et al [15]; homogeneous particles (≈300-400 nm sized) were prepared by micro-emulsion method with sintering at 800 °C [12]; 300-nm LMO nanoparticles were grown by hydrothermal synthesis following by sintering at 700 °C for 10 h [46]; LMO submicron-crystal LMO were prepared by ball milling and heat treated in the range 750-900 °C [30]; Molenda et al [50] reported the growth of nanosized LMO using a modified sol-gel method followed by calcination at 650 °C. To conclude, there is an experimental fact that 650 °C is the lowest temperature to prepare nanocrystalline LMO.…”

“…To overcome these disadvantages and prepare particles of smaller size, many wetchemical methods are being used, which include micro-emulsion [11][12], hydrothermal synthesis [13], sol-gel [14], microwave-induced combustion [15], and spray drying method [16].…”

Synthesis and electrochemical properties of Li-rich spinel type LiMn2O4 powders by spray pyrolysis using aqueous solution of manganese carbonate

“…Spinel type LiMn 2 O 4 cathode materials [2] are thought to be promising for lithium ion batteries in EVs and HEVs, owing to advantages such as low cost, abundant source materials, non-toxicity and high thermal stability. To date, various techniques for preparing LiMn 2 O 4 cathode materials via liquidphase reactions [3][4][5][6][7][8][9][10] or solid-state reactions [11][12][13] have been developed in order to improve the electrochemical properties of the materials, including the cycling stability, rechargeable capacity and recharging rate. We have focused on spray pyrolysis among the liquid-phase reactions.…”

Effect of β-Cyclodextrin on Electrochemical Properties of LiMn₂O₄ Synthesized by Solid-State Combustion Synthesis

“…Very faint diffraction peaks at 23.2°, 32.9° and 55.1° corresponding to the diffractions of Mn 2 O 3 (PDF, No.24-0508) can be observed. This was because the temperature is not high enough to realize full crystallization of LiMn 2 O 4 [12]. When β-cyclodextrin was added by 5 wt%, 10 wt% and 20 wt%, the enhanced diffraction peaks were identified as a single phase of cubic spinel LiMn 2 O 4 structure with the space group Fd3m and no notable variation of secondary phase or impurities for the samples were observed.…”