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1.
Thin cuprous oxide films have been prepared by chemical vapor deposition (pulsed spray evaporation-chemical vapor deposition) method without post-treatment. The synthesis ofcuprous oxide was produced by applying a water strategy effect. Then, the effect of water on the morphology, topology, structure, optical properties and surface composition of the obtained films has been comprehensively investigated. The results reveal that a pure phase of Cu2O was obtained. The introduction of a small quantity of water in the liquid feedstock lowers the band gap energy from 2.16 eV to 2.04 eV. This finding was mainly related to the decrease of crystallite size due to the effect of water. The topology analyses, by using atomic force microscope, also revealed that surface roughness decreases with water addition, namely more uniform covered surface. Moreover, theoretical calculations based on density functional theory method were performed to understand the adsorption and reaction behaviors of water and ethanol on the Cu2O thin film surface. Formation mechanism of the Cu2O thin film was also suggested and discussed.  相似文献   
2.
A versatile synthetic strategy for the preparation of multimetallic oxynitrides has been designed and here exemplarily discussed considering the preparation of nanoscaled zinc–gallium oxynitrides and zinc–gallium–indium oxynitrides, two important photocatalysts of new generation, which proved to be active in key energy related processes from pollutant decomposition to overall water splitting. The synthesis presented here allows the preparation of small nanoparticles (less than 20 nm in average diameter), well-defined in size and shape, yet highly crystalline and with the highest surface area reported so far (up to 80 m2 g−1). X-ray diffraction studies show that the final material is not a mixture of single oxides but a distinctive compound. The photocatalytic properties of the oxynitrides have been tested towards the decomposition of an organic dye (as a model reaction for the decomposition of air pollutants), showing better photocatalytic performances than the corresponding pure phases (reaction constant 0.22 h−1), whereas almost no reaction was observed in absence of catalyst or in the dark. The photocatalysts have been also tested for H2 evolution (semi-reaction of the water splitting process) with results comparable to the best literature values but leaving room for further improvement.  相似文献   
3.
本文采用一步脉冲雾化化学气相沉积法在250℃下制备了氧化亚铜薄膜催化剂.实验研究了前驱体中掺杂水对氧化铜薄膜表面形貌、拓扑结构、表面成分和光学特性的影响规律.结果表明所制得的催化剂为纯相的氧化亚铜.前驱体溶液中掺杂水会导致氧化亚铜的晶粒变小,从而使得共光学能隙从2.16 eV降至2.04 eV.原子力显微镜结果表明随着水的加入,氧化亚铜的表面粗糙度降低,表面更加均匀.此外,利用密度泛函理论计算得到了水和乙醇在氧化亚铜薄膜表面的吸附和反应特性,并提出了氧化亚铜的形成机理.本文开发了一种低成本且实际可行的薄膜制造方法,该方法在太阳能电池和半导体等领域具有潜在应用.  相似文献   
4.
The CaCu3Mn4O12 (CCMO) ceramic was successfully synthesized through the chemical route. The phase formation was confirmed by the X-ray diffraction pattern. Thermogravimetric (TGA), FT-IR, SEM, TEM, EDX, and XPS analysis were performed for investigation of the thermal behavior, phase identification, microstructural analysis, elemental analysis and oxidation state of the CCMO ceramic respectively. FT-IR spectra confirmed the existence of MnO6 octahedral in body-centered cubic (BCC) complex perovskite oxide that resembles the CaCu3Ti4O12 structure. The average particle size was observed by TEM in the range between 100 and 200 nm. AFM shows the average roughness of the surface was found to be in the range of 30 ± 5 nm. XPS and EDX studies confirmed the purity and oxidation state of the CCMO ceramic. The synthesized material shows very interesting unique Griffith’s phase (TG) results that arise disorder in magnetic susceptibility in which ferromagnetic transition was to be observed in the paramagnetic region.  相似文献   
5.
BixOyBrz光催化剂在有机药物废水处理领域有着非常广阔的潜在应用价值,但因光生电子和空穴的快速复合而表现出较低的光催化效率,进而限制了其应用范围。通过简易的水解-焙烧法原位制得一种新型的Bi3O4Br/Bi12O17Br2复合光催化剂,并以磺胺甲噁唑(SMX)为模拟药物污染物进行了光催化性能测试,对所制催化剂进行了X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、紫外可见漫反射光谱(UV-Vis DRS)、电化学阻抗(EIS)、光致发光光谱(PL)等表征。结果表明所制备的Bi3O4Br/Bi12O17Br2复合光催化剂具有较强的光生载流子分离率、较低的界面电荷转移电阻,进而展示出优异的光催化降解SMX性能,在模拟太阳光下照射30 min,SMX降解率达到87%,相较于纯的Bi3O4Br和Bi12O17Br2催化剂,降解率分别提升了30%和24%。最后基于自由基捕获实验和催化剂能带结构分析了所制催化剂的降解机理。  相似文献   
6.
全固态电池因其高能量密度和高安全性而成为具有发展前景的下一代储能技术。开发具有高室温离子电导率、优异化学/电化学稳定性、良好正/负极兼容性的固态电解质是实现全固态电池实用化的关键。卤化物固态电解质因其优异的电化学窗口、高正极稳定性、可接受的室温锂离子电导率等优势,受到了广泛的关注。本文通过对近年来卤化物电解质的相关研究进行总结,综述了该类电解质的组成、结构、离子传导路径及制备方法,并分析了金属卤化物电解质的电导率、稳定性特点,归纳了近年来该电解质在全固态电池中具有代表性的应用,并基于以上总结和分析,指出了卤化物固态电解质的研究难点及发展方向。  相似文献   
7.
螺旋桨结构的三苯胺荧光团既能作为强的电子供体,又能作为潜在的聚集诱导发光(AIE)骨架.同时,三苯胺衍生物很容易通过简单的反应进行结构修饰,如醛基、氨基、硼酸基、卤素、乙炔基等取代的三苯胺能够发生缩合反应或偶联反应等,进一步功能化.因此,功能性三苯胺类化合物被广泛用于太阳能电池、荧光染料、固态发光材料和荧光探针的分子设计中.根据三苯胺基荧光探针的检测对象,将其分为阳离子、阴离子和中性小分子荧光探针三类,并从分子的结构和性能出发,重点综述了近五年来国内外三苯胺基荧光探针在分子设计、合成与检测应用方面的最新进展.展望未来,构建近红外发光和高量子效率的AIE荧光探针值得关注.  相似文献   
8.
Developing sustainable routes for the synthesis of zeolites is still a vital and challenging task in zeolite scientific community. One of the typical examples is sustainable synthesis of aluminosilicate EU-1 zeolite, which is not very efficient and environmental-unfriendly under hydrothermal condition due to the use of a large amount of water as solvent. Herein, we report a sustainable synthesis route for aluminosilicate EU-1 zeolite without the use of solvent for the first time. The physicochemical properties of the obtained EU-1 zeolite are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2 sorption, inductively coupled plasma (ICP) analysis, and solid nuclear magnetic resonance (NMR), which show the product has high crystallinity, uniform morphology, large BET surface area, and four-coordinated aluminum species. Moreover, the impact of synthesis conditions is investigated in detail. The sustainable synthesis of aluminosilicate EU-1 zeolite under solvent-free  相似文献   
9.
The synthesis of unsubstituted oligo-para-phenylenes ( OPP ) exceeding para-hexaphenylene—in the literature often referred to as p-sexiphenyl—has long remained elusive due to their insolubility. We report the first preparation of unsubstituted para-nonaphenylenes ( 9PP s) by extending our precursor route to poly-para-phenylenes ( PPP ) to a discrete oligomer. Two geometric isomers of methoxylated syn- and anti-cyclohexadienylenes were synthesized, from which 9PP was obtained via thermal aromatization in thin films. 9PP was characterized via optical, infrared and solid-state 13C NMR spectroscopy as well as atomic force microscopy and mass spectrometry, and compared to polymeric analogues. Due to the lack of substitution, para-nonaphenylene, irrespective of the precursor isomer employed, displays pronounced aggregation in the solid state. Intermolecular excitonic coupling leads to formation of H-type aggregates, red-shifting emission of the films to greenish. 9PP allows to study the structure–property relationship of para-phenylene oligomers and polymers, especially since the optical properties of PPP depend on the molecular shape of the precursor.  相似文献   
10.
以F127为模板剂,Ni Cl2为镍源,尿素为氮源,间苯二酚甲醛原位聚合树脂为碳源,分别采用均相法和两相法制备Ni-NOMC-1,Ni-N-OMC-2纳米复合材料。X射线衍射(XRD)、激光拉曼以及透射电子显微镜(TEM)等测试结果表明,复合材料具有有序介孔结构,Ni以金属微粒形式嵌于碳骨架中,提高了有序介孔碳的石墨化程度。X射线光电子能谱测试(XPS)表明尿素热解后以4种形式存在:sp3杂化与C结合的N原子,吡啶N原子,sp2杂化与C结合的N原子以及quaternary-N原子。Ni-N的共改性改变了碳载体的理化性质,有利于Pt纳米粒子的负载与分散。均相法制备的Ni-N-OMC-1复合材料微波负载Pt后,氧还原极限电流密度为5.32 m A·cm-2,氢氧化电化学活性面积高达138.53 m2·g-1,电化学催化活性优于商业20%Pt/C材料(4.49 m A·cm-2,96.98 m2·g-1)。  相似文献   
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