Borolan-2-yl involving anion acceptors for organic liquid electrolyte-based fluoride shuttle batteries
Borolan-2-yl involving anion acceptors for organic liquid electrolyte-based fluoride shuttle batteries
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用于基于有机液态电解质的氟化穿梭电池的硼兰-2-基阴离子受体
DOI：
10.1016/j.jfluchem.2020.109672
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发表时间：
2020-12-01
影响因子：
1.9
通讯作者：
Abe, Takeshi
中科院分区：
文献类型：
--
作者：
Kucuk, Asuman Celik;Abe, Takeshi
硼基阴离子受体（AAs）被用于解离有机液体电解质氟离子穿梭电池（FSBs）中的MF盐（CsF）。本文研究了两种硼基化合物4-（4,4,5,5-四甲基-1,3,2-二恶硼罗伦-2-基）吡啶（DiOB-Py）和N，N-二乙基-4-（4,4,5,5-四甲基-1,3,2-二恶硼罗伦-2-炔苯胺）（DiOB-An）作为含CsF的G4电解质添加剂。DiOB-Py和DiOB-An在结构上相似，只是前者是用吡啶官能化的，而后者是用苯胺官能化的。由于DiOB-Py中的吡啶通过共振效应抽离苯基环上的电子对，硼酸盐的路易斯酸度增加。另一方面，由于苯胺的孤对电子通过共振效应给予苯基环，DiOB-An中硼酸盐的酸度降低。已知AAs具有中等强的氟亲和性，可在电解质溶剂中充分溶解CsF。因此，研究了硼酸盐的酸性强度对BiF3电化学相容性的影响。DiOB-Py赋予了相对较高的氟离子电导率和CsF溶解度，从而增强了FSB性能。
Boron-based anion acceptors (AAs) have been used to dissociate MF salt (CsF) in organic liquid electrolyte-based fluoride shuttle batteries (FSBs). Here, two boron-based compounds, 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (DiOB-Py) and N,N-diethyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yeaniline) (DiOB-An), were examined as electrolyte additives for G4 containing CsF. DiOB-Py and DiOB-An are structurally similar except that the former is functionalized with pyridine whereas the latter with aniline. Since pyridine in DiOB-Py withdraws an electron pair on the phenyl ring via the resonance effect, the Lewis acidity of borate increases. On the other hand, since lone pair electrons of aniline are donated to the phenyl ring through the resonance effect, the acidity of borate in DiOB-An decreases. AAs are known to have a moderately strong fluoride affinity to provide sufficient dissolution of CsF in the electrolyte solvent. Thus, the effects of the acidity strength of the borates on the electrochemical compatibility of BiF3 were investigated. DiOB-Py imparted relatively high fluoride ion conductivity and CsF solubility, thereby allowing enhanced FSB performance.