Influence of Sm3+ ion in structural, morphological, and electrochemical properties of LiMn2O4 synthesized by microwave calcination

Abstract

LiSm x Mn 2-x O 4 samples were synthesized via coprecipitation technique. The structural properties of the synthesized materials were studied using X-ray diffraction analysis and it confirmed the cubic spinel structure for all the compounds. The lattice parameter of LiMn 2 O 4 was observed to be 8.2347 Ǻ and it decreased with Sm 3+ concentration, due to the shrinkage in cell volume aided by higher binding energy between Sm-O bond. The SEM micrographs were analyzed using Image processing software (Image-J) to ascertain the pore and grain properties. The microwave synthesis had been observed to control the bulk grain formation and had yielded lesser porous and nanoparticles. The particle size distributions obtained through photocross correlation laser diffraction analysis had shown that LiMn 2 O 4 with 60 nm and Sm-doped compounds with ∼30 nm, respectively. The cyclic voltammetry studies had revealed the decrease in electrocatalytic behavior in the initial cycle for compounds doped with Sm 3 + ion. The initial capacities of LiMn 2 O 4 , LiSm 0.05 Mn 1.95 O 4 and LiSm 0.10 Mn 1.90 O 4 substituted compounds were observed to be 134.87 mAhg −1 , 132.22 mAhg −1 and 126.41 mAhg −1 , respectively. The cells were simulated using 1D model namely Dualfoil5.1 program. The simulated results coincide well with the measured results. The cycle life studies reveal 93% capacity retention of samarium-0.05-doped samples when compared with 78.4% of the LiMn 2 O 4 .

Electrochemical performance of rare-earth doped LiMn2O4 spinel cathode materials for Li-ion rechargeable battery

“…Nd doped LiMn 2 O 4 by chemical precipitation and calcination was researched by Singhal and Das [21], who reported that LiNd 0.01 Mn 1.99 O 4 has the highest discharge capacity (149 mA hg −1 ) and has a capacity retention of about 91% after 25 cycles. Balaji and Mutharasu [22] …”

Preparation and Doping Mode of Doped LiMn2O4 for Li-Ion Batteries

“…Sometimes, the method is not used alone, but rather more than one method [44] is used in a preparation.…”

“…The common raw materials used are carbonates [22,78], acetates [79], nitrates [44,71], sulfates [80], hydroxides [73], oxides [81] of Li, Mn and the doped-ion. The preparation processes are various.…”

“…For instance, the nonmetals B [10][11][12], F [13][14][15], S [16], Br [17], the general metals Mg [18], Al [19], Ti [20,21], Cr [22,23], Fe [24], Co [19,[25][26][27], Ni [28], Cu [29], Zn [30][31][32], Ga [33], Zr [34], Ru [35], Ag [36,37], Sn [38], Au [39], the rare-earth metals La [40], Ce [41], Pr [42], Nd [43], Sm [44], Gd [45], and the actinide dopants Th [46], U [47]. Some researchers have also modified LiMn 2 O 4 with surface coating [48][49][50][51][52] electrolyte modification [53], laser annealing [54], pulsed laser deposition [55], process optimization …”

Synthesis, effect of γ-ray and electrical conductivity of uranium doped nano LiMn2O4 spinels for applications as positive electrodes in Li-ion rechargeable batteries

“…The substitution increases the average oxidation state of Mn above 3.5, and hence, suppressing Jahn-Teller distortion, stabilizes the crystal structure of the spinel. All dopant elements are less or close to that of Mn, but few reports about the rareearth elements have been published [30][31][32][33][34][35]. Here, we aim to go further and use uranium for metal substitution of LiMn 2 O 4 spinel.…”