556-63-8Relevant articles and documents
An ESR and ENDOR study of irradiated 6Li-formate
Komaguchi,Matsubara,Shiotani,Gustafsson,Lund,Lund
, (2007)
Lithium formate (6LiOOCH·H2O), 95% 6Li enrichment, combined with an exchange of crystallization water with D2O was investigated. The ESR spectrum of the radiation induced free radicals stable at room temperature
Masuda, Yoshio,Hashimoto, Kazuhito,Ito, Yoshio
, p. 271 - 278 (1990)
The Effect of Water on Quinone Redox Mediators in Nonaqueous Li-O2 Batteries
Liu, Tao,Frith, James T.,Kim, Gunwoo,Kerber, Rachel N.,Dubouis, Nicolas,Shao, Yuanlong,Liu, Zigeng,Magusin, Pieter C. M. M.,Casford, Michael T. L.,Garcia-Araez, Nuria,Grey, Clare P.
, p. 1428 - 1437 (2018/02/09)
The parasitic reactions associated with reduced oxygen species and the difficulty in achieving the high theoretical capacity have been major issues plaguing development of practical nonaqueous Li-O2 batteries. We hereby address the above issues by exploring the synergistic effect of 2,5-di-tert-butyl-1,4-benzoquinone and H2O on the oxygen chemistry in a nonaqueous Li-O2 battery. Water stabilizes the quinone monoanion and dianion, shifting the reduction potentials of the quinone and monoanion to more positive values (vs Li/Li+). When water and the quinone are used together in a (largely) nonaqueous Li-O2 battery, the cell discharge operates via a two-electron oxygen reduction reaction to form Li2O2, with the battery discharge voltage, rate, and capacity all being considerably increased and fewer side reactions being detected. Li2O2 crystals can grow up to 30 μm, more than an order of magnitude larger than cases with the quinone alone or without any additives, suggesting that water is essential to promoting a solution dominated process with the quinone on discharging. The catalytic reduction of O2 by the quinone monoanion is predominantly responsible for the attractive features mentioned above. Water stabilizes the quinone monoanion via hydrogen-bond formation and by coordination of the Li+ ions, and it also helps increase the solvation, concentration, lifetime, and diffusion length of reduced oxygen species that dictate the discharge voltage, rate, and capacity of the battery. When a redox mediator is also used to aid the charging process, a high-power, high energy density, rechargeable Li-O2 battery is obtained.
Coordination environments and π-conjugation in dense lithium coordination polymers
Tominaka, Satoshi,Yeung, Hamish H.-M.,Henke, Sebastian,Cheetham, Anthony K.
, p. 398 - 406 (2016/01/16)
The understanding of lithium-oxygen coordination systems is important for making better lithium conductors as well as active materials for lithium ion batteries. Here, we report a systematic investigation on coordination environments in lithium coordination polymers (LCPs) through the syntheses and analyses of six new crystals composed of lithium ions and anthraquinone (aq) derivative anions, where the negative charges are distributed in π-conjugation systems. Their structures were determined by single-crystal X-ray diffraction to be (1) [Li2(23dcaq)(H2O)] in space group P21/c, (2) [Li(23dcaqH)] in P21/c, (3) [Li2(15dhaq)(H2O)2] in P21/c, (4) [Li2(14dhaq)(H2O)2] in Pnma, (5) [Li(14dhaqH)(H2O)] in P212121 and (6) [Li(14hnaq)(H2O)] in P212121 (23dcaq2- = 2,3-dicarboxy-aq, 14dhaq2- = 1,4-dihydroxy-aq, 15dhaq2- = 1,5-dihydroxy-aq and 14hnaq- = 1-hydroxy-4-nitro-aq). Through the comprehensive structure analysis of these materials as well as other LCPs, we found that when considering the longest C-O bond in the π-conjugation system of an anionic organic molecule and its coordination to a Li ion, there is a weak inverse relationship between the C-O and Li-O bond lengths. In addition, despite exhibiting optical band edges below 2 eV and 1D π-stacking connectivity, conductivity measurements on single crystals of 1-6 confirmed that they are all electronic insulators. We rationalize this finding on the basis of π-orbital delocalization, which is more restricted in the aq-based LCPs compared to known semiconducting hybrid materials.
