Recent Advancements of Hexaazatriphenylene-Based Materials for Energy Applications

Abstract

Hexaazatriphenylene (HAT) is an electron deficient, rigid, planar, aromatic discotic molecule with three fused pyrazine rings and excellent π-π stacking ability. Due to its excellent topology and electronic properties, HAT has been exploited as structural motifs of supramolecules, covalent organic frameworks (COFs), porous hydrogen-bonded organic frameworks (HOFs), and metal organic frameworks (MOFs). HAT derivatives have been utilized in catalysis, semiconductors, monomolecular magnets, water oxidation, proton conduction, etc. In recent years, motivated by the increasing energy demand, scientists have intensively studied the energy applications of HAT derivatives. In this paper, the recent progress of HAT derivatives in the field of energy has been reviewed. Keywords tripyrazine (HAT) derivatives; energy application; covalent organic framework 三亚吡嗪(Hexaazatriphenylene, HAT) (Scheme 1), 由三个稠合的吡嗪环构成, 具有良好的对称性, sp 2 杂化 作用使它拥有出色的电子缺陷性质和高 π-π 堆积趋势. 作为刚性且平面的氮杂芳香族骨架, HAT 是最小二维含 氮的多环芳香族体系. 1981 年 Nasielski-Hinkens 等 [1] 报 道了 HAT 的合成, 由于结合了独特拓扑结构和电子特 征以及强配位能力, HAT 吸引了科学家们的研究兴趣, 不断涌现出基于 HAT 的聚合物、大分子、配合物等. 近 年来, 随着有机多孔材料 [2] 的发展, HAT 作为构建新型 多孔聚合物的明星构建基块 [3] 被广泛用于构筑新型金属 配合物 [4] 、固有微孔聚合物(PIMs) [5] 、共轭微孔聚合物 图式 1 HAT 的结构 Scheme 1 Structure of HAT (CMPs) [6] 、多孔氢键有机框架(HOFs) [7] 和共价有机框架 (COFs) [8] . 通过对 HAT 的修饰和构建, HAT 衍生物已被 广泛应用于质子传导 [9] 、催化剂 [10] 、半导体 [11] 、单分子 磁体 [12] 、气体分离 [13] 、水氧化 [14] 和电化学储能 [15] 等众 有机化学 综述与进展 4168 http://sioc-journal.cn/

Research status and prospect of electrode materials for lithium-ion battery

“…Moreover, the technology for producing lithium nickel cobalt manganese oxide by coprecipitation and subsequently sintering with lithium carbide at high temperatures is becoming more sophisticated. It can significantly lower the cost of employing LiCoO2 and increase safety [17].…”

“…During the discharge process of the battery with LiMn2O4 as positive electrode, LiMn2O4 is inclined to change to tetragonal structure when lithium is excessively embedded in it [17]. The fatal defect seriously affected the cycle performance of the battery.…”

“…The fatal defect seriously affected the cycle performance of the battery. To improve the cycle stability, researchers have proposed that appropriate metal ions or other anions can be added to LiMn2O4 [17].…”

“…The major flaw in LiCoO2 is its poor thermal resistance, and when the charging voltage increases, its own safety performance frequently degrades [17]. Nevertheless, LiCoO2 cannot be effectively employed in high-power and large-capacity batteries due to its high pollution, toxicity, and lack of raw materials as well as its market price [18].…”