Study of formation of LiCoO2 using a modified Pechini aqueous sol–gel process

Predoană, Luminița; Jitianu, Andrei; Voicescu, Mariana; Apostol, Nicoleta G.; Zaharescu, M.

doi:10.1007/s10971-014-3611-2

Cited by 8 publications

(16 citation statements)

References 54 publications

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“…The choice of cation precursors for Li ion battery cathodes are typically nitrates and sometimes acetates (Predoana et al 2015). Some exceptions exist, for instance was SiO2 particles used in the synthesis of Li2FeSiO4 (giving a colloidal suspension) (Dominko et al 2008) and tetra-n-butyl titanate was used to dope LiMn2O4 with titanium (Xiong et al 2012).…”

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

“…The first report of Pechini synthesis of LiMn2O4 used EG as a solvent (Liu et al 1996), but it has since become increasingly common to use aqueous solutions (Kunduraci and Amatucci 2006;Predoana et al 2015).…”

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

“…Both of these factors had a large impact on the electrochemical performance of the cathode material, and the optimal ratio between CA and EG was found to be 1:4. Other authors have applied only CA (Predoana et al 2015) or a combination of CA and EDTA (Liu et al 2014). Duncan et al used EG without a carboxylic acid for the preparation of LiMn1.5Ni0.5O4 (Duncan et al 2010).…”

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

“…The calcination temperature has been shown to be an important parameter to optimize the electrochemical properties of the cathode materials. First of all, the volatility of Li at high temperatures is well known (Rossen et al 1993), and sometimes an excess of Li is used in the solution to compensate for this (Predoana et al 2015). Furthermore, a low calcination temperature will give smaller particle sizes, giving a high discharge capacity, however, the crystallinity of the particles can often be impaired, leading to fast capacity fading (Zhao et al 2013).…”

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

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Modified Pechini Synthesis of Oxide Powders and Thin Films

Sunde

Grande

Einarsrud

2016

Handbook of Sol-Gel Science and Technology

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The modified Pechini method has become one of the most popular synthesis methods for complex oxide materials due to its simplicity and versatility. The method can be applied to synthesize nano-crystalline powders, bulk materials as well as oxide thin films. Here, we present a comprehensive review of the method with focus on the chemistry through the three stages of the process; preparation of stable aqueous solution, poly-esterification to form a solid polymeric resin and finally decomposition/combustion of the resin to form an amorphous oxide followed by crystallization of the desired oxide phase. The review include

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Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

Section: Cathode Materials For LI Ion Batteriesmentioning

confidence: 99%

See 2 more Smart Citations

Modified Pechini Synthesis of Oxide Powders and Thin Films

Sunde

Grande

Einarsrud

2016

Handbook of Sol-Gel Science and Technology

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“…18 For this reason, the sol-gel method has been widely used modulating these properties. 6,[18][19][20][21][22][23][24][25][26][27][28] The sol-gel method allows a larger surface area for the obtained solids, in our study the LiCoO 2 powder. In addition, this technique also enables a smaller Li-ion diffusion length due to the reduced LiCoO 2 Freitas et al 2255 Vol.…”

mentioning

confidence: 99%

Synthesis and Characterization of LiCoO2 from Different Precursors by Sol‑Gel Method

Freitas

Siqueira

Costa

et al. 2017

J. Braz. Chem. Soc.

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Lithium cobalt oxide, LiCoO 2 , widely used as cathode in lithium ion batteries was synthesized and their structural and electronic properties investigated. The crystalline powders were prepared by the sol-gel method with four complexing agents: citric acid, glycine, starch and gelatin. These syntheses were compared with the blank test (without complexing agent). The X-ray diffraction and vibrational spectroscopy allowed the identification of the rhombohedral phase LiCoO 2 ( ) as the only or principal crystalline component in all samples. A small fraction of a second phase of cubic spinel Co 3 O 4 was observed in the samples of starch, gelatin and the blank test. The Rietveld refinements showed small structural variations, indicating reduced influence of the complexing agents on the synthesis. The theoretical HOMO-LUMO (highest occupied molecular orbital-lowest unoccupied molecular orbital) gap values are in agreement to those estimated by diffuse reflectance spectroscopy (DRS). The scanning electron microscopy (SEM) showed morphological pattern regardless of the complexing agent used, showing an alternative method.Keywords: LiCoO 2 , sol-gel method, XRD, Rietveld refinement, lithium ion batteries, DFT IntroductionLithium cobalt oxide, LiCoO 2 , has been the focus of many studies regarding their structural and electronic properties. [1][2][3][4][5][6][7][8] This system has interesting electrochemical features that allows a wide use as cathodes of lithium ion batteries. 2,4 The investigation of the structural aspects of the material is a crucial issue to better understand the electrochemical properties of the LiCoO 2 compound. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] For example, the nature of the crystal, its size and shape, are directly related with its electrochemical characteristics. 2 The LiCoO 2 synthesized at low temperatures (LT), below 500 °C, presents a cubic spinel structure ( ), while the synthesis at high temperatures (HT) (above 500 °C), generates the rhombohedral structure with stratified layers ( ). Therefore, several authors usually classify these structures as LT-LiCoO 2 and HT-LiCoO 2 , respectively . 1,2,7,8,[18][19][20][21][22][23][24] The rhombohedral phase is characterized by a structure with alternating layers of cobalt and lithium cations intercalated with oxygen anions. 22 The lithium and cobalt(III) ions are arranged in intercalated layers (Figure 1a). The cobalt(III) ion is located at the octahedral sites, forming a strong bond with the neighboring oxygen anion to constitute the Co−O layers (Figure 1b). Finally, the lithium layers are intercalated between the CoO 2 plans. 1,3,4 The octahedral sites of these layers are occupied by lithium and cobalt(III) ions alternately that forms a sequential stacking with oxygen ion layers in a close packing of the ABCABC type ( Figure 1c). 4,5 This specific stacking arrangement leads to an environment equivalent for all ions, allowing the maximum charge delocalization and the minimal system energy. 1,3,4 The degree of crystal orde...

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