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本文综述了溶剂热法合成多种碳纳米管、纳米电缆、纳米棒、纳米球和纳米空心锥的研究现状。350 ℃下用金属钾还原六氯代苯,在用不同催化剂时,可分别得到碳纳米管和碳球,碳球的形成可以解释为石墨层的微条卷曲而成。600 ℃下金属镁还原乙醇得到了竹节状和Y-型碳纳米管。500 ℃下还原四氯化碳和碳酸钠可得到平均直径为100 nm的碳纳米管。700 ℃下金属锌还原乙醚制成了左右螺旋型交织的碳纳米管。在硫的存在下,200 ℃以下二茂铁热解成非晶碳纳米管和Fe/非晶碳纳米同轴电缆。 相似文献
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在路易斯酸催化下,碳硼烷分别与对氰基溴化苄、三苯基膦在甲苯溶液里回流,前者反应中,制备得碳硼烷的硼端与对氰基苄基中的亚甲基直接偶联的产物1,通过调整催化剂的含量,可以显著地提高含B-Cl键的产物2的产率;与三苯基膦的反应中,碳硼烷失去一个硼顶,并与三苯基膦中的P原子直接偶联,生成含B-P键的巢式碳硼烷衍生物3。对此两类化合物进行了核磁、质谱、红外及单晶衍射等表征。化合物1和2中均发现碳硼烷的CH与N形成CH…N氢键和CH…π的弱作用,其中化合物2中,还存在CH…Cl。在巢式化合物3中,发现碳硼烷的CH参与了罕见的CH…HC相互作用。这类反应成功合成了含有B-C、B-Cl、B-P键的碳硼烷衍生物。 相似文献
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SiC single crystals have been prepared by the method of solvothermal synthesis with a system of SiCl4, CCl4 and metal K in an auto clave. X-ray diffraction (XRD), Raman spectra and transmission electron microscopy(TEM) were used to characterize the products. XRD reveals that the products are SiC crystals and TEM exhibits that SiC single crystal sofwires and platelets are obtained under different usages of metal K. The SiC wires have diameters of 10~20 nm and length up to 1.5μm; the platelets have lateral dimensions of 0.1~3 μm, exhibiting regular polygonal shapes and step-bunched side surface. Furthermore, the growth mechanism of the SiC single crystals is discussed and the effect of super saturation on the crystal growth and morphology is also investigated. 相似文献
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含能笼型碳硼烷衍生物的合成及其热性能 总被引:1,自引:0,他引:1
以DMSO或DMF为溶剂,1-溴甲基碳硼烷(1)分别与亚硝酸钠和叠氮钠发生亲核取代反应,合成了两种新型的含能笼型碳硼烷——1-硝基甲基碳硼烷(2)和1-叠氮基甲基碳硼烷(3),其结构经1H NMR和FT-IR表征。用DSC分析了1~3的热性能,结果表明:1和2分别在162.2℃和168.7℃分解,分解热分别为130.4 J.g-1和245.6 J.g-1。 相似文献
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在溶剂热条件下, 以三乙烯四胺(TETA)作为模板剂, 合成出具有一维链状结构的硫酸铟化合物(C6H22N4)0.5[In(OH)](SO4)2(1). 采用红外光谱、热重分析、ICP、元素分析、粉末X射线衍射及单晶X射线衍射等手段对其进行了表征. 结果表明, 化合物1属于单斜晶系, P2(1)/c空间群, a=1.05240(3) nm, b=1.36802(4) nm, c=0.75295(2) nm, β=101.558(2)°, V=1.06204(5) nm3, Z=4, R1=0.0368, wR2=0.0897, GOF=1.068. 其结构是由InO4(OH)2八面体和SO4四面体通过共顶点连接形成的一维阴离子Tancoite-type 链. 质子化的TETA阳离子通过与阴离子链中的O原子之间的氢键作用将一维链连接成为三维超分子结构. 相似文献
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以乙酸锌和Se粉为原料,环己酮为溶剂,于180 ℃反应24 h制得黄色纳米球ZnSe,其结构和性能经XRD,SEM及TEM表征. 相似文献
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Eggshell-like carbon materials with high yields have been synthesized by a solvothermal route in a stainless steel autoclave using metallic zinc and absolute ethanol as starting materials. The products were characterized by X-ray powder diffractometry (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy and scanning electron microscopy (SEM). The eggshell-like carbon spheres had diameters ranging from 500 nm to 1 μm. The optimal reaction conditions to obtain eggshell-like carbon materials were 600 ℃ and 12 h. 相似文献
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具有四配位铁中心的微孔磷酸铁晶体的溶剂热合成与表征 总被引:4,自引:0,他引:4
在有机溶剂乙二醇中合成了具有三维骨架结构的磷酸铁晶体 ,对其进行了单晶结构解析 ,热重分析 ,穆斯堡尔谱以及红外光谱测试 ,证实晶体组成为 [NH3CH2 CH2 NH3]0 .5[FePO4 ],晶体结构属正交晶系 ,空间群Pc cn ,晶胞参数a =10 .36 1(6 ) ,b =10 .390 (5) ,c=9.135(7) ,V =983.3(11) 3,Z =8,Dc=2 .4 57Mg·m- 3,F(0 0 0 ) =72 8,R =0 .0 52 8,wR =0 .1194。在其结构中 ,磷氧四面体和铁氧四面体严格交替共用顶点在 [0 0 1]方向上形成八员环 ,双质子化的乙二胺分子占据八员环空隙。该晶体结构最为显著的特征是具有在磷酸盐中非常少见的四配位铁中心 相似文献
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Sea-urchin-like ZnO nanomaterials were successfully synthesized by decomposition of zinc acetate precursor in the presence of sodium hydroxide and ethylene glycol(EG) in an ethanol solution using a solvothermal method at 180 ℃ for 12 h.The crystalline phase and morphology of the resultant nanomaterials were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),selected-area electronic diffraction(SAED) and high-resolution electron microscopy(HRTEM).Interestingly,the sizes and prod length of the samples can be easily tuned by changing the amount of directing agent EG and keeping other reaction conditions unchangeable.On the basis of our experimental outcomes,EG-controlled-nucleation-growth formation mechanism was proposed to correspond for the sea-urchin-like ZnO growth processes.And the photoluminescence(PL) spectra of the as-selected samples were measured at room temperature,presenting two emission peaks centered at~388 and 480 nm. 相似文献
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Prof. Richard I. Walton 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(42):9041-9069
Perovskite oxides with general composition ABO3 are a large group of inorganic materials that can contain a variety of cations from all parts of the Periodic Table and that have diverse properties of application in fields ranging from electronics, energy storage to photocatalysis. Solvothermal synthesis routes to these materials have become increasingly investigated in the past decade as a means of direct crystallisation of the solids from solution. These methods have significant advantages leading to adjustment of crystal form from the nanoscale to the micron-scale, the isolation of compositions not possible using conventional solid-state synthesis and in addition may lead to scalable processes for producing materials at moderate temperatures. These aspects are reviewed, with examples taken from the past decade's literature on the solvothermal synthesis of perovskites with a systematic survey of B-site cations, from transition metals in Groups 4–8 and main group elements in Groups 13, 14 and 15, to solid solutions and heterostructures. As well as hydrothermal reactions, the use of various solvents and solution additives are discussed and some trends identified, along with prospects for developing control and predictability in the crystallisation of complex oxide materials. 相似文献
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利用水热方法制备了正交氮化硼微晶, 于400 ℃时制备的氮化硼结晶质量较高, 主要物相为正交氮化硼(oBN). 在反应原料中加入水合肼和氯化铵都有利于样品结晶质量的改善和产率的提高. 在合成氮化硼反应过程中, 适当减慢反应体系的升温速率有利于提高oBN的结晶质量和产率, 但是当升温速率过慢时, oBN的稳定性有所降低, 立方氮化硼(cBN)的稳定性则在一定程度上得到提高. 此外, 反应过程中的原料配比对样品的物相及其结晶质量也有很大影响. 相似文献
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The hexagonal born nitride based yellow afterglow phosphor was prepared by the rapid combustion method and its luminescent properties were characterized. The phosphor prepared at 800 ℃ for 30 min is with excellent luminescent performance. After irradiation by UV light, the yellow long-lasting phosphorescence can be observed for above 2 h in the limit of light perception of dark-adapted human eyes(0.32 mcd·m-2). 相似文献
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Kang Hyuck Lee Dr. Hyeon‐Jin Shin Dr. Brijesh Kumar Han Sol Kim Jinyeong Lee Dr. Ravi Bhatia Dr. Sang‐Hyeob Kim In‐Yeal Lee Dr. Hyo Sug Lee Prof. Gil‐Ho Kim Prof. Ji‐Beom Yoo Dr. Jae‐Young Choi Prof. Sang‐Woo Kim 《Angewandte Chemie (International ed. in English)》2014,53(43):11493-11497
Unintentionally formed nanocrystalline graphene (nc‐G) can act as a useful seed for the large‐area synthesis of a hexagonal boron nitride (h‐BN) thin film with an atomically flat surface that is comparable to that of exfoliated single‐crystal h‐BN. A wafer‐scale dielectric h‐BN thin film was successfully synthesized on a bare sapphire substrate by assistance of nc‐G, which prevented structural deformations in a chemical vapor deposition process. The growth mechanism of this nc‐G‐tailored h‐BN thin film was systematically analyzed. This approach provides a novel method for preparing high‐quality two‐dimensional materials on a large surface. 相似文献
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DunQingWANG DaiRongCHEN XiuLingJIAO 《中国化学快报》2004,15(1):79-82
Pyrite nickel disulfide and millerite nickel monosulfide have been successfully prepared by solvothermal method based on the reaction of Ni(NO3)26H2O and H2NC(S)NH2 in benzene and ethylenediamine (EDA). The final products were characterized by X-ray powder diffraction(XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM). The effects of the solvent, reaction temperature and time on the morphology and phase of the products have been discussed. 相似文献
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含镧的Bi2Te3基化合物的溶剂热合成及微观结构 总被引:5,自引:1,他引:5
以BiCl3,LaCl3和Te粉为原料,用溶剂热合成法制备了含稀土元素的单相LaxBi4Te6(x≤1)热电材料纳米粉末.研究发现,三元化合物LaxBi4Te6具有与二元Bi2Te3化合物相同的晶体结构和相似的晶格常数。LaxBi4Te6中的La含量随合成温度升高而增加,但与反应时间没有显著关系。LaxBi4Te6合成粉末的颗粒尺寸在30nm左右,并且几乎与反应温度和反应时间没有关系。在120℃合成的粉末基本上为不规则多面体形状,在150℃及以上温度合成的粉末则趋向于薄片状.并存在一些直径在50~80nm之间的纳米管。 相似文献