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141.
Michael F. Rectenwald Joshua R. Gaffen Prof. Arnold L. Rheingold Dr. Alexander B. Morgan Prof. John D. Protasiewicz 《Angewandte Chemie (International ed. in English)》2014,53(16):4173-4176
The functionalized catecholate, tetraethyl (2,3‐dihydroxy‐1,4‐phenylene)bis(phosphonate) (H2‐DPC), has been used to prepare a series of lithium salts Li[B(DPC)(oxalato)], Li[B(DPC)2], Li[B(DPC)F2], and Li[P(DPC)3]. The phosphoryl‐rich character of these anions was designed to impart flame‐retardant properties for their use as potential flame‐retardant ions (FRIONs), additives, or replacements for other lithium salts for safer lithium‐ion batteries. The new materials were fully characterized, and the single‐crystal structures of Li[B(DPC)(oxalato)] and Li[P(DPC)3] have been determined. Thermogravimetric analysis of the four lithium salts show that they are thermally stable up to around 200 °C. Pyrolysis combustion flow calorimetry reveals that these salts produce high char yields upon combustion. 相似文献
142.
Hiroshi Sakai Takashi Yamazaki Nobuya Machida Toshihiko Shigematsu Saburo Nasu 《Molecular Crystals and Liquid Crystals》2013,570(2):105-110
Abstract Mössbauer spectra of the FePS3-cobaltocene intercalation compound were measured in the temperature range of 300K to 10K. The spectra, distinct from those of pure FePS3, suggest the charge transfer from cobaltocene to Fe-S antibonding orbitals of the FePS3 host lattice. 相似文献
143.
Sambandan Ekambaram Masaru Yanagisawa Satoshi Uchida Yoshinobu Fujishiro Tsugio Sato 《Molecular Crystals and Liquid Crystals》2013,570(2):213-218
Abstract TiO2 and Pt have been intercalated in hectorite and H4Nb6O17. The height of TiO2 and Pt pillars was less than 0.8 nm and the band gap energy of TiO2 pillars was ca. 3.3 eV. Both hectorite/TiO2 and H4Nb6O17(Pt, TiO2) were capable of hydrogen evolution following irradiation from a high pressure mercury are (λ > 290 nm) in the presence of methanol as a sacrificial hole acceptor and the hydrogen evolution was enhanced by co-incorporation of Pt, although hectorite and hectorite/Pt did not show photocatalytic activity. Incorporation of Pt or Pt and TiO2 in the interlayer of H4Nb6O17 has resulted in enhanced photo evolution of hydrogen, however, TiO2 alone in the interlayer of H4Nb6O17 showed adverse photocatalytic activity. 相似文献
144.
145.
Abstract The reaction of aluminum alkoxide in straight-chain primary alcohols at elevated temperatures yielded the alkyl derivatives of boehmite [AlO(OH)1-x (OR) x ], a class of intercalation compound where the guest moieties are covalently bonded to the host boehmite layers. The addition of small amounts of water to the reaction system yielded another phase having a larger basal spacing. XRD, IR, and elemental analysis showed that the products had the boehmite layer structure with the alkyl moieties incorporated between the boehmite layers. IR spectra of the products also exhibited bands due to hydrogen bonding between the boehmite layers. These results suggest that the products are the alkyl derivatives of boehmite having the second stage structure. Because water in the reaction medium facilitated the hydrolysis of intermediate aluminum alkoxides, the product with the second stage structure had smaller alkyl/Al ratio and therefore had smaller basal spacing than that expected from the corresponding first stage product. 相似文献
146.
Organobentonite (OBT)/sodium polyacrylate (PAAS) composite material was prepared. The OBT/PAAS humidity-control cement-based mortars were prepared by mixing OBT/PAAS in mortar. Its morphology and structure were characterized by environmental scanning electron microscope (ESEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and the Brunauer-Emmett-Teller (BET) method. The results showed that the morphology and humidity-control capacity of OBT/PAAS mortar are superior to those of the original mortar. The OBT/PAAS mortar had larger pore specific surface area and larger pore volume, corresponding to the most probable pore diameter, than that of mortar. There was no chemical reaction between mortar and OBT/PAAS and there was no new crystal structure generated. The prepared, solidified OBT-PAAS mortar can maintain humidity in a desiccator at 38~62 RH%. 相似文献
147.
148.
MgO et ZnO, modified by addition of a solvent or a metal salt, give very selective reactions by an interfacial solid-liquid process. 相似文献
149.
石墨烯由于拥有超高比表面积和超高电导率而被作为电化学电容器材料广泛研究.本文采用树脂为碳源,通过一种方便快捷的树脂交换法制备一种具有高比表面积的多级孔三维石墨烯(3DG).经过此种方法的催化、造孔、热处理等主要工艺步骤后,可显著增加石墨烯材料的小、介孔数量,从而提高材料的电化学性能.通过BET测试表明,3DG的比表面积可达2400 m2/g,孔体积达到2.0 cm3/g.以3DG作为正负极材料制备高比能量高功率型锂离子电容器(3DG-LIC),可使3DG-LIC的工作电压从传统超级电容器的2.5 V扩展到4.0 V,能量密度也从20 Wh/kg提高到105 Wh/kg.另外,相同的化学和微观结构能很好地平衡正负极的容量及速率,使高比能量高功率的3DG-LIC具有更宽阔的应用领域. 相似文献
150.
Wan-Yue Diao Dan Xie Yan-Fei Li Ru Jiang Fang-Yu Tao Prof. Hai-Zhu Sun Prof. Xing-Long Wu Dr. Xiao-Ying Zhang Prof. Jing-Ping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(31):8168-8177
Lithium metal anodes (LMAs) with high energy density have recently captured increasing attention for development of next-generation batteries. However, practical viability of LMAs is hindered by the uncontrolled Li dendrite growth and infinite dimension change. Even though constructing 3D conductive skeleton has been regarded as a reliable strategy to prepare stable and low volume stress LMAs, engineering the renewable and lithiophilic conductive scaffold is still a challenge. Herein, a robust conductive scaffold derived from renewable cellulose paper, which is coated with reduced graphene oxide and decorated with lithiophilic Au nanoparticles, is engineered for LMAs. The graphene cellulose fibres with high surface area can reduce the local current density, while the well-dispersed Au nanoparticles can serve as lithiophilic nanoseeds to lower the nucleation overpotential of Li plating. The coupled relationship can guarantee uniform Li nucleation and unique spherical Li growth into 3D carbon matrix. Moreover, the natural cellulose paper possesses outstanding mechanical strength to tolerate the volume stress. In virtue of the modulated deposition behaviour and near-zero volume change, the hybrid LMAs can achieve reversible Li plating/stripping even at an ultrahigh current density of 10 mA cm−2 as evidenced by high Coulombic efficiency (97.2 % after 60 cycles) and ultralong lifespan (1000 cycles) together with ultralow overpotential (25 mV). Therefore, this strategy sheds light on a scalable approach to multiscale design versatile Li host, promising highly stable Li metal batteries to be feasible and practical. 相似文献