Synthesis of Cu vanadate nanorods for visible‐light photocatalytic degradation of gentian violet

Cu vanadate nanorods have been synthesized via the hydrothermal process using polymer polyvinyl pyrrolidone (PVP) as the surfactant. X‐ray diffraction (XRD) shows that the nanorods are composed of monoclinic Cu₅V₂O₁₀ phase. Scanning electron microscopy (SEM) observation shows that the diameter and length of the nanorods are 50–300 nm and 3 μm, respectively. PVP concentration, hydrothermal temperature and duration time play essential roles in the formation and sizes of the Cu vanadate nanorods. A PVP‐assisted nucleation and crystal‐growth process is proposed to explain the formation of the Cu vanadate nanorods. Gentian violet (GV) is used to evaluate the photocatalytic activities of the Cu vanadate nanorods under solar light. The GV concentration clearly decreases with increasing irradiation time, and content of the Cu vanadate nanorods. GV solution with the concentration of 10 mg L⁻¹ can be totally degraded under solar light irradiation for 4 h using 10 mg Cu vanadate nanorods. The Cu vanadate nanorods have good photocatalytic activities for the degradation of GV under solar light.     

Preparation of dendritic‐like CdS by hydrothermal method and its photocatalytic performance

In this article, dendritic‐like CdS has been prepared by a hydrothermal method using thiourea as the sulfur source, and the effects of experimental conditions on the morphologies of CdS have been investigated. The performances of CdS have been analyzed by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and the fluorescence and photodegradation properties of CdS have also been investigated. The XRD result indicates that the dendritic‐like CdS are of hexagonal phase and they are highly crystallized. Also, the FESEM results show that the ratio of raw material affects the yield of CdS, the reaction time affects the morphology of CdS. The best morphology of CdS is dendritic structures and the length is about 6 μm. The fluorescence spectrum shows three peaks at 470 nm, 513 nm and 547 nm, which indicates that the dendritic‐like CdS mainly emits green and blue fluorescence. Moreover, the dendritic‐like CdS exhibits good photocatalytic activity and its photodegradation rate to methylene blue can reach 92%. The growth mechanism for the formation of CdS with dendritic structure is also described.     

Optical properties of flower‐like CdS prepared by a hydrothermal method with SDBS as surfactant

In this article, flower‐like CdS structures have been prepared by a hydrothermal method with SDBS as surfactant. The influences of different experimental conditions on the morphologies, UV‐Vis and fluorescence properties of CdS have been investigated. The performances of CdS have been analyzed by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet‐visible (UV–Vis) and room‐temperature photoluminescence (PL). The XRD result indicates that the flower‐like CdS structures are of hexagonal phase. The FESEM results indicate that the main role of SDBS is to make the CdS crystals assemble together to form the flower‐like structures. The UV–Vis results show CdS has a strong absorption in the ultraviolet region and visible‐light region. The PL results show CdS has two emission peaks, respectively at 461 nm and 553 nm. The growth mechanism for the formation of flower‐like CdS structures is also described.     

α‐Fe2O3 Cubes with High Visible‐Light‐Activated Photoelectrochemical Activity towards Glucose: Hydrothermal Synthesis Assisted by a Hydrophobic Ionic Liquid

A liquid/liquid interfacial reaction system was designed to fabricate α‐Fe₂O₃ cubes. The reaction system uses a hydrophobic ionic liquid containing iron ions ([(C₈H₁₇)₂(CH₃)₂N]FeCl₄) for manufacturing α‐Fe₂O₃ cubes by a novel and environmentally friendly hydrothermal method under low‐temperature conditions (140 °C). The iron‐containing ionic liquid is hydrophobic and can form a liquid/liquid interface with water, which is vital for fabrication of the α‐Fe₂O₃ cubes. Nanomaterials synthesized from hydrophobic iron‐containing ionic liquids show good crystallinity, well‐developed morphology, and uniform size. The effect of different ionic liquids on the morphology of α‐Fe₂O₃ was investigated in detail. [(C₈H₁₇)₂(CH₃)₂N]FeCl₄ is assumed to perform the triple role of forming a liquid/liquid interface with water and acting as reactant and template at the same time. The effect of the reaction temperature on the formation of the α‐Fe₂O₃ cubes was also studied. Temperatures lower or higher than 140 °C are not conducive to formation of the α‐Fe₂O₃ cubes. Their photoelectrochemical properties were tested by means of the transient photocurrent response of electrodes modified with as‐prepared α‐Fe₂O₃ cubes. The photocurrent response of an α‐Fe₂O₃ cubes/indium tin oxide electrode is high and stable, and it shows great promise as a photoelectrochemical glucose sensor with high sensitivity and fast response, which are beneficial to practical applications of nanosensors.     

Highly Flexible and Nonflammable Inorganic Hydroxyapatite Paper

A highly flexible and nonflammable inorganic hydroxyapatite (HAP) paper made from HAP ultralong nanowires is reported. The paper can be used for printing and writing and is promising for the permanent and safe storage of information, such as archives and important documents. The HAP paper is also an excellent and recyclable adsorbent for organic pollutants.     

不同形貌纳米CoWO_4的水热法制备及气敏性能(英文)

以Co(NO3)2·6H2O、Na2WO4·2H2O为主要原料,去离子水为溶剂,利用水热法在不同条件下制备了一系列的纳米CoWO4,用XRD、TEM和比表面分析仪对产品的物相、形貌和比表面积进行了表征。较系统地探讨了水热条件(反应混合物pH值、反应时间、反应温度等)对产物物相和形貌的影响,并研究了不同形貌产品对甲醛、乙醇、氨气、苯和丙酮等的敏感性能。结果表明:水热条件对产品的物相和形貌有影响,在不同水热条件下,可成功制备CoWO4纳米颗粒、纳米立方体及纳米棒;以纳米颗粒、纳米立方体及纳米棒样品制成的气敏元件对被试气体有不同程度的响应,其中以纳米颗粒为基的元件在210℃对1 000μL·L-1NH3灵敏度为3.3。     

十三氟辛基修饰的疏水有机-无机杂化二氧化硅膜孔结构、氢气分离及水热稳定性

采用1,2-双(三乙氧基硅基)乙烷(BTESE)和十三氟辛基三乙氧基硅烷(PFOTES)为前驱体,在酸性条件下通过溶胶-凝胶法制备了十三氟辛基修饰的有机-无机杂化SiO2膜材料。利用接触角测量、红外光谱、动态光散射和N2吸附等测试技术分别对膜材料的疏水性、溶胶粒径和孔结构进行表征,并深入研究有支撑膜材料的氢气渗透、分离性能以及长期水热稳定性。结果表明,十三氟辛基修饰后的膜材料由亲水性变成了疏水性,当nPFOTES/nBTESE=0.6时膜材料对水的接触角达到(110.4±0.4)°,膜材料还保持微孔结构,孔径分布在0.5~0.8 nm。氢气在修饰后的膜材料中的输运遵循微孔扩散机理,在300℃时,氢气的渗透率达到8.5×10-7mol·m-2·s-1·Pa-1,H2/CO2,H2/CO和H2/SF6的理想分离系数分别为5.49,5.90和18.36,均高于相应的Knudsen扩散分离因子。在250℃且水蒸气物质的量分数为5%水热环境下陈化250 h,氢气渗透率和H2/CO2的理想分离系数基本保持不变,膜材料具有良好的水热稳定性。     

Graphene oxide assisted facile hydrothermal synthesis of LiMn0.6Fe0.4PO4 nanoparticles as cathode material for lithium ion battery

Assisted by graphene oxide（GO）,nano-sized LiMn0.6Fe0.4PO4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn0.6Fe0.4PO4（S2）was about 80 nm in diameter.The discharge capacity of LiMn0.6Fe0.4PO4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn0.6Fe0.4PO4 and it in situ reduction of GO could improve the electrical conductivity of LiMn0.6Fe0.4PO4 material.     

准立方体纳米α-Fe_2O_3的制备及光催化活性研究

本文利用无表面活性剂条件,以氨水和醋酸锌为形貌调控剂,通过水热法合成了准纳米立方块结构的α-Fe2O3。并利用X射线衍射、透射电子显微镜、扫描电子显微镜对产物的形貌进行了的表征,对其形成机理进行了初步的解释。同时对其光催化降解活性进行了研究。     

二氧化锰纳米管模拟氧化酶的性能、抑制剂及其对Pb2+的测定

采用简便的水热法,获得了具有氧化酶催化特性的二氧化锰纳米管,研究了其对氧气(O2)氧化3,3',5,5'-四甲基联苯二胺(TMB)发生显色反应的催化性能,重点考察了常见金属离子对其活性的抑制作用。结果表明,能与MnO2表面发生特异性吸附络合作用的Pb2+的抑制作用最为显著。基于该抑制作用,建立了针对铅离子的高灵敏、快速检测新方法。结果显示,铅的线性范围为1.0×10-7~1.0×10-3 mol/L,检出限为3.0×10-8 mol/L。