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通过微乳液法及其辅助的溶剂热法制备出了不同形貌的SrMoO4粉体材料,探讨了工艺参数对SrMoO4材料形貌的影响。微乳液体系中表面活性剂十六烷基三甲基溴化铵(CTAB)浓度、反应物浓度及溶剂热过程中反应时间、CTAB浓度都会对SrMoO4材料的形貌造成影响。通过调整上述工艺参数可以调控SrMoO4材料的形貌,得到了近球状、哑铃状、纺锤体状、花簇状等特殊形貌的SrMoO4微晶材料。SrMoO4样品的室温光致发光谱是由发光中心在约420nm处的单一紫光组成,样品的形貌不同发光强度和发光峰位置略有不同。 相似文献
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以硫酸亚铁、尿素及乙醇为原料,采用低温常压一步回流法制备了具有三维花状结构的α-FeOOH纳米材料.考察了反应时间、反应温度、尿素浓度和乙醇用量对其结构和形貌的影响及α-FeOOH纳米材料对双氯芬酸钠的吸附性能.实验结果表明,当反应温度为90℃、反应时间为6 h、尿素浓度为0.1 mol/L、乙醇的体积分数为20%时,所得α-FeOOH纳米材料具有规整的三维花状结构,对双氯芬酸钠的吸附量达199.2mg/g.基于扫描电子显微镜(SEM)和X射线衍射(XRD)分析,推断三维花状结构α-FeOOH的生长机制包括定向聚集和外延生长2个过程,反应初期生成的高活性晶核快速形成不规则橄榄状颗粒并定向聚集成短簇状结构,再沿z轴方向外延生长,形成长簇的三维花状结构. 相似文献
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核壳结构AlOOH的制备、表征及其生长机制 总被引:1,自引:0,他引:1
在柠檬酸钠和硝酸铝水溶液体系中, 通过一步水热法制备了蜷缩刺猬状和核壳结构的AlOOH微球, 并用X射线衍射(XRD)、Fourier变换红外(FTIR)光谱、扫描电镜(SEM)、透射电镜(TEM)、氮气吸脱附和光致发光等分析手段对制备的样品进行了形貌和结构表征. 对反应时间、反应物浓度等影响因素进行了研究. 实验结果表明: 反应时间和反应物柠檬酸钠的浓度对所得AlOOH微球结构的尺寸和形貌具有重要影响; 蜷缩刺猬状和核壳结构AlOOH微球都具有较大的比表面积, 分别为171.5和178.6 m2·g-1; 不同形貌的AlOOH具有不同的荧光发射峰. 并初步探讨了核壳结构AlOOH微球的生长机制. 相似文献
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用水热和溶剂热法(甲苯作溶剂)合成了LiSrAlF6单相多晶.研究了反应物摩尔比、反应温度和反应时间等对产物的影响.采用环境扫描电子显微镜观察到LiSrAlF6晶体的形貌特征为六角晶形,并聚集成花朵形.试探了LiCaAlF6多晶粉末的水热和溶剂热合成,但未能获得纯相产物. 相似文献
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采用Co(NH3)6Cl3为钴源,利用微乳法制备了Co3O4的纳米材料,可控合成了尺寸均一的边长约40~50 nm纳米立方和直径约400 nm的纳米球.并且考察了反应条件对产物形貌的影响,水与CTAB的摩尔比(w)和反应物浓度对产物形貌有着很大的影响,而反应温度对产物形貌基本没有影响.随着w值的增加,合成的纳米材料的尺... 相似文献
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微波对碱式碳酸镁结晶过程的影响 总被引:1,自引:0,他引:1
在微波外场作用下,利用氯化镁和碳酸钠溶液反应结晶法直接合成碱式碳酸镁晶体。通过对比微波、水浴两种加热方式下镁离子变化曲线和产物的差异,XRD、FTIR,SEM等对相转移过程的物相分析表征,探索微波对反应的强化影响。结果表明,反应结晶直接合成碱式碳酸镁过程分为絮状物→出现晶体→完全转变为球状碱式碳酸镁3个阶段。微波对反应3个阶段中都有强化作用,促进絮状物的形成,加快相转变,提高反应转化率,微波加热条件下在粒径分布与组装方式与水浴加热方式均有不同,微波作用下较小颗粒是由纳米片层平行组装而成,而较大颗粒可能是无定形物在球状小颗粒表面继续转变,形成交错的表层纹理的大颗粒碱式碳酸镁。 相似文献
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回流法可控合成BiPO4纳米棒及其光催化性能 总被引:1,自引:0,他引:1
采用回流法合成了BiPO4纳米棒光催化剂, 探讨了反应时间、反应物比例、pH值和反应物浓度对BiPO4晶相结构和形貌尺寸的影响, 利用粉末X射线衍射(XRD)、透射电镜(TEM)、比表面积分析(BET)和紫外-可见漫反射光谱(UV-Vis DRS)等对产物进行了表征, 以亚甲基蓝(MB)为探针研究了其光催化活性. 反应时间和反应物浓度对产物的形貌尺寸影响较大, 反应物比例和pH值对产物晶相结构和形貌尺寸均有较大的影响, 进一步影响BiPO4光催化剂的活性. 调控各种因素后可合成出具有单斜相独居石/六方相混晶结构的高紫外光活性BiPO4纳米棒光催化剂. 相似文献
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采用软模板法,以十二烷基硫酸钠(SDS)为模板剂,经水热合成制得三维花状双金属(Mg Al)氢氧化物(3D-Mg Al LDH)。通过XRD、FT-IR、SEM及TEM等表征手段,研究了原料Mg/Al物质的量之比、SDS浓度及反应时间对产物微观结构和表面形貌的影响规律,并初步探讨了3D-Mg Al LDH的形成机理。结果表明,当n_(Mg)/n_(Al)=2,SDS浓度为0.1 mol·L~(-1),水热反应时间为6 h时,可形成结晶度良好、花球形貌完整,纳米片厚度均一的三维花状LDH。在3D-Mg Al LDH的形成过程中,SDS既以阴离子形态参与LDH形成,又因其类球状胶束特性附着在已形成的LDH表面或边缘诱导LDH纳米片交叉生长形成三维花状。吸附实验表明,3D-Mg Al LDH对非离子型有机污染物具有良好的吸附作用,最大吸附量约为31 mg·g~(-1),去除率达到100%。 相似文献
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Li-Xia Yang Ying-Jie Zhu Hua Tong Zhen-Hua Liang Liang Li Ling Zhang 《Journal of solid state chemistry》2007,180(7):2095-2101
Nickel hydroxide nanosheets and flowers have been hydrothermally synthesized using Ni(CH3COO)2·4H2O in mixed solvents of ethylene glycol (EG) or ethanol and deionized water at 200 °C for different time. The phase and morphology of the obtained products can be controlled by adjusting the experimental parameters, including the hydrothermal time and the volume ratio of water to EG or ethanol. The possible reaction mechanism and growth of the nanosheets and nanoflowers are discussed based on the experimental results. Porous nickel oxide nanosheets are obtained by heating nickel hydroxide nanosheets in air at 400 °C. The products were characterized by using various methods including X-ray diffraction (XRD), fourier transform infrared (FTIR), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), field emission scanning electron microscopy (FESEM). The electrochemical property of β-Ni(OH)2 nanosheets was investigated through the cyclic voltammogram (CV) measurement. 相似文献
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Yan Gu Fengwen Yan Cun-Yue Guo Guoqing Yuan 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(8):1614-1620
The complex rose-like inorganic templates assembled by the ZnO/ZnO2 hybrid nanosheets have been constructed with hydrogen peroxide as an additive to control the structure of a precursor. The surface morphologies of the inorganic templates can be controlled by varying the reaction time and the amount of hydrogen peroxide. The process of the precursor growth takes a dissolution-growth route under hydrothermal conditions. The chemical composition of the precursor is determined by X-ray diffraction (XRD) and Raman analyses, indicating the existence of peroxide in the precursor. Combined with transmission electron microscopy (TEM) data, the ZnO/ZnO2 hybrid precursor is proposed to act as an inorganic template for the growth of secondary crystal structures. The dandelion-like ZnO crystal is fabricated by using rose-like peroxide precursor as the inorganic template. The structural evolution of hierarchical ZnO crystal is studied by monitoring the influence of the reaction time. 相似文献
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Mao-Mao RUAN Le-Xin SONG Qing-Shan WANG Juan XIA Zun YANG Yue TENG Zhe-Yuan XU 《物理化学学报》2017,33(5):1033-1042
This work reports a controlled green synthesis of highly monodisperse bismuth subcarbonate (BS) micropompons self-assembled by nanosheets using a simple and facile hydrothermal route in which deionized water, bismuth nitrate pentahydrate (BNP), and urea were used as the solvent, bismuth source, and carbon source respectively. Trisodium citrate dihydrate (TCD) was used as a coordination agent to fabricate a complex precursor. The structure and morphology of the BS materials can be finely modulated by adjusting the initial concentration ratios of the reactants or the reaction time. The presence of TCD decreased the formation rate of BS due to a direct competitive interaction for the BiO+ ions between a coordination equilibrium and a precipitation equilibrium. Urea played a crucial role (e.g., carbon source, alkaline source, morphology control agent, and crystal growth control agent) in the formation of the BS microstructures. We obtained three kinds of BS crystals with preferred orientations along [001], [110], and [013] by adjusting the concentration of urea. Our synthesis approach has the advantages of low cost, high reaction yields, monodisperse particles, controlled morphologies and orientations, and not requiring the use of organic solvents, templates, surfactants, high phototemperatures, and long reaction times. Particularly, when compared with those reported by other investigators, the micropompon material exhibited improved photocatalytic performance for Rhodamine B due to a unique microstructure (large specific surface area, high efficiency of photoelectric conversion, small interfacial chargetransfer resistance, and active {001} exposed facets). These results indicate a major advance in the controlled green synthesis and the application of inorganic micro-and nano-materials. 相似文献
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