Surface trace doping of Na enhancing structure stability and adsorption properties of Li1.6Mn1.6O4 for Li+ recovery
Abstract
Li1.6Mn1.6O4 (LMO) is a dominant adsorbent for lithium recovery from solutions resulted from its high theoretical adsorption uptake and a low loss rate of Mn, which can potentially be further improved by trace doping. We achieve stable cycling and high adsorption capacity of Li1.6Mn1.6O4 from aqueous lithium resources through surface trace doping of Na (LMO-Na). The dissolution of Mn is reduced from 5.4% (before doping) to 4.4%, and the adsorption uptake is increased from 33.5 mg/g to 33.9 mg/g at Li+ concentration of 24 mmol/L. In addition, first-principles calculations further confirm that Na substitutes for Li at 16d sites, leading to an improvement of the Li+ uptake rate and stabilizing the Mn cations in the compound. With the help of Na doping, the undesired dissolution of Mn in the cycling process is inhibited, which may result from reducing the content of the low valent Mn3+ and improving the structural stability of the adsorbent. The effect of the Na substitution on adsorption capacity and structure stability is discussed.
Citation
Qian , F , Zhao , B , Guo , M , Wu , Z , Zhou , W & Liu , Z 2020 , ' Surface trace doping of Na enhancing structure stability and adsorption properties of Li 1.6 Mn 1.6 O 4 for Li + recovery ' , Separation and Purification Technology , vol. In press . https://doi.org/10.1016/j.seppur.2020.117583
Publication
Separation and Purification Technology
Status
Peer reviewed
ISSN
1383-5866Type
Journal article
Description
The work was supported by the NSFC (No: 51302280 and No: U1607105), the Scientific and Technological Funding in Qinghai Province, China (No:2018-GX-101, No:2018-ZJ-722 and No:2019-HZ-808,), the Thousand Talents Plan in Qinghai province and Youth Innovation Promotion Association of Chinese Academy of Sciences (No:2016377).Collections
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