纳米SnO2的制备

ＳｎＯ２在陶瓷、气敏半导体材料及催化剂等方面被广泛应用［１］．纳米级的ＳｎＯ２因具有明显的表面效应而受到关注，其制备方法也受到重视［２］．纳米ＳｎＯ２的制备方法较多，有沉淀法［２］、水热法［３，４］、溶胶－凝胶法［５］、火焰合成法［６］等．然而要制备...     

铜和金纳米线阵列上SCN-的表面增强拉曼光谱

纳米材料的制备和性质研究已成为化学和物理等领域中的热点［１～４］．例如,一些纳米尺度的金属表现出极高的催化活性;一些低维的半导体纳米点（零维）、线（一维）、面（二维）材料被认为在半导体信息工业中将占有举足轻重的地位．最近有关金属和半导体纳米线的研究正在兴起,其特殊的电学和光学性质引起了广泛兴趣,并有可能制备成为各类尺寸极小的纳米电极［２］．迄今已有多种技术用于研究和表征金属以及半导体纳米线的特殊性质［２,５～９］,其中紫外可见吸收光谱和荧光光谱是广泛使用的表征纳米线光学性质的技术［２,５,６］．…     

金纳米粒子组装结构中的表面重组现象

以纳米粒子为基本结构单元构筑的各种二维或三维超晶格结构受到了广泛的重视［１］．人们的兴趣一方面来源于在纳米尺度上控制材料结构 ,另一方面则因为组织化的纳米材料或结构具有独特的性质 ,以期在非线性光学、纳米电子学等前沿领域得到应用［２］．当前研究最多的结构形式是固体表面上的纳米粒子阵列或单层薄膜 ,通常是胶体粒子靠某种特殊相互作用吸附或沉积在固体表面上（亦称为“纳米粒子在表面上的组装［３］”） ,因此对纳米粒子及固体表面进行功能化的修饰 ,从而控制纳米粒子在表面上的排列和聚集状态 ,是制备这类复合结构的核心问…     

氧化铁超微粒的光电化学特性

近十年来,。J、粒1（smalParticle）或超微粒f（ultrafinParticle）研究在化学、物理、材料学科等领域中兴起［‘一‘］．超微粒子是指粒径在Inm～几十n－m范围的物质山．快体（如金属、半导体）的性质并不是单个原子或分子本身的性质,而是由许多原子或分子在晶体中的周期排列造成的．当晶体的尺寸在纳米级范围内连续减小时,存在一个从金属或半导体的性质到分子或原子的性质的逐渐过渡．在这个变化范围内,半导体的光学性质有很大变化,金属的电化学行为也发生了变化．这被称为“尺寸量子化效应’．同时当半导体的尺寸在纳米范围时,其…     

TiO2纳米粒子膜表面性质的研究

ＴｉＯ_２纳米粒子膜在光催化降解大气和水中的污染物［１］、光电转换［２］、光致变色［３］等方面有广阔的应用前景,近年来受到了科学界的高度重视．研究表明,膜的表面性质对如上应用有着重要影响．本文采用等离子体化学气相沉积法（ＰＥＣＶＤ法）［４］制备了ＴｉＯ２的纳米粒子膜,分别采用ＴｉＣｌ４等离子体或Ｏ２等离子体处理膜表面,获得两种不同表面性质的ＴｉＯ２纳米粒子膜;并利用表面光电压谱（ＳＰＳ）和电场诱导表面光电压谱（ＥＦＩＳＰＳ）技术对膜的表面性质进行具体分析,探讨了其在光催化领域的可能应用．１实验部…     

金纳米粒子通过形成Au-S键的组装

利用湿化学法以纳米粒子为基本单元构筑各种纳米复合结构,具有灵活简便、通用性强等特点,近年来受到了广泛的重视．Ｎａｔａｎ［１-４］等最先开展了在固体表面上制备金纳米粒子单层膜的研究,他们借助双官能团硅烷化试剂对硅氧化物基底（如玻璃、石英等）进行表面修饰?..     

乙醇溶液中ZnO纳米粒子的形成机理研究

半导体纳米粒子的研究是当今材料科学及物理化学的热门课题[1－3]．由于纳米粒子具有极大的比表面、尺寸量子化效应及增强的氧化和还原能力等不同于扶林的特殊性质，它被广泛地用于光催化，光电材料的制备及非线性光学材料的研究等[4－6]．ZnO作为一种重要的半导体材料，其纳米粒子的制备近年来也有报导[7－14]．由于ZnO在水中的生成自由能较正，所以一般都在醇溶液中制备，但其具体的成核机理至今并不十分清楚．本工作通过仔细的研究，阐明了ZnO纳米粒子形成过程中的成核和生长机理．1实验部分醋酸锌，氢氧化钠和乙醇均为分析纯试剂．制…     

油溶性金属Ni纳米微粒的制备与表征

纳米材料的制备、性能与应用已成为近年来的研究热点之一犤１犦。由于在催化、光学和电学材料中的广泛应用，超细单分散的金属微粒的制备与性质已引起人们的广泛兴趣。通常制备金属纳米微粒的方法有两种：一是把固体金属材料分裂为纳米尺寸的颗粒，如机械粉碎、电弧放电及金属原子蒸气沉积犤２犦，用这种方法制备的金属微粒粒径一般都比较大，且粒子尺寸分布宽，另一种是把金属原子制成纳米尺度的颗粒，如乳液聚合法犤３犦、热解犤４犦、γ－射线辐照犤５犦、脉冲电沉积犤６犦和化学还原犤７犦等，这种方法制备的微粒粒径通常分布窄且粒子小…     

二氧化钛超薄膜的组装

近年来LB膜技术和超微粒子研究的发展，将两者有效地结合起来组装了与量子电子学、非线性光学、光电化学、化学生物传感器有关的纳米量级无机半导体材料［‘－‘j．其中TIO。纳米薄膜材料已在太阳能电池反射膜、压电铁电薄膜、电致显示器件［‘j、可逆光电池和超导薄膜［’］研究中都显示了广阔的应用前景．这类薄膜制备多采用化学气相沉积（CVD）技术和原子层外延．也有人把LB技术应用于纳米粒子的组装来制备TIO。超薄膜［”’j二本文利用烷氧基钛在水／空气界面上发生的溶胶一凝胶化反应制备TIO。基胶态粒子及其固态凝聚膜，将其与…     

氧化锌纳米微晶的顺磁共振特性

半导体纳米微粒是制备新一代电子器件的理想材料［1，2］．电子自旋共振谱（ESR）是研究纳米微晶表面电子自旋构象和表面结构的一种有效方法．体相ZnO是一种抗磁性物质，通常观察不到顺磁共振信号（ESR）．有关ZnO纳米微晶电子顺磁共振特性研究还未见文献报导．本文ZnO纳米微晶是用微乳法制备的：这样就制成了纳米尺度的具有表面包覆的ZnO微粒有机溶胶．这里表面活性剂起着“空间位阻”作用，一方面防止成胶过程中粒子间的聚合，使胶粒均匀细小；另一方面，包覆能减少微粒表面缺陷，使粒子性质变得十分稳定．将上述制得的ZnO纳米微粒…     

纳米Ag/ZnO光催化剂及其催化降解壬基酚聚氧乙烯醚性能

采用氨浸法制备了不同Ag负载量的纳米Ag/ZnO光催化剂,并用X射线衍射、比表面积测定、X射线光电子能谱和漫反射紫外-可见光谱测定了Ag/ZnO的晶型结构、比表面积、表面组成和光谱特征.以壬基酚聚氧乙烯醚(NPE-10)为模型污染物,分别在紫外光和可见光照射下考察了纳米Ag/ZnO的光催化活性.结果表明,Ag能成功地负载到ZnO表面,且随着Ag负载量的增加,ZnO的粒径逐渐增大,比表面积逐渐减小.与纳米ZnO样品相比,Ag/ZnO中Ag 3d5/2结合能减小,而Zn 2p和O 1s结合能增大,ZnO表面的羟基氧和吸附氧含量增加.当Ag负载量大于0.5%时,Ag/ZnO样品的吸收光谱发生红移,在可见光区出现吸收.光催化降解结果表明,0.5%Ag/ZnO样品的光催化活性最高,在紫外光和可见光照射3 h后NPE-10降解率分别约为77%和56%,而ZnO样品的光催化活性仅约为61%和40%.     

Synthesis and thermo-physical properties of water-based novel Ag/ZnO hybrid nanofluids

The comparative study on the thermo-physical properties of water-based ZnO nanofluids and Ag/ZnO hybrid nanofluids is reported in the present study. The outer surface of ZnO nanoparticles was modified with a thin coating of Ag nanoparticles by a wet chemical method for improved stability and heat transfer properties. The ZnO and Ag/ZnO nanofluids were prepared with varying volume concentration (??=?0.02–0.1%). The synthesized nanoparticles and nanofluids were characterized with different characterization methods viz., scanning electron microscopy, X-ray diffraction, dynamic light scattering, thermal conductivity measurement, and viscosity measurement. Results show that thermal conductivity of Ag/ZnO hybrid nanofluids is found to be significantly higher compared to ZnO nanofluids. The maximum thermal conductivity an enhancement for Ag/ZnO nanofluid (??=?0.1%) is found to 20% and 28% when it compared with ZnO nanofluid (??=?0.1%) and water, respectively.     

复合Ag/ZnO分级结构微球的制备及其光催化性能研究

采用化学沉淀法制备ZnO微球,利用柠檬酸三钠（TCD）避光还原硝酸银在ZnO表面沉积银粒子制备Ag/ZnO复合材料.利用XRD、SEM、TEM、EDS、FTIR、UV-vis DRS、PL、BET等对Ag/ZnO的结构、组分、形貌及光谱性质进行了表征,通过紫外及可见光照降解甲基橙溶液评价样品的光催化性能.结果表明：ZnO纳米微球是由ZnO纳米片相互交错构筑而成的具有丰富孔道的分级结构,Ag纳米粒子均匀沉积在ZnO纳米片上.Ag的沉积显著增加了ZnO的可见光吸收,猝灭了ZnO荧光,提高了ZnO催化活性.     

Bacteria and bacteriophage inactivation by silver and zinc oxide nanoparticles

Microbial contaminants such as bacteria and viruses are of great concern in water. As nanotechnology continues to grow, understanding the interactions of nanoparticles with bacteria and viruses is important to protect public health and the environment. In this study, the effect of two commonly used nanoparticles, silver nanoparticles (AgNPs, average particle size=21 nm) and zinc oxide nanoparticles (ZnO NPs, average particle size=39 nm), on the growth of bacteria (Eschericia coli) and bacteriophages (MS2) were evaluated using a standard double agar layer (DAL) method and a turbidimetric microtiter assay. A 1-h prior exposure of MS2 to nanoparticles did not inactivate MS2 at the highest nanoparticle concentrations tested (5mg/L total Ag and 20 mg/L ZnO). No bacteriophage inactivation was observed in the presence of AgNPs, Ag(+)/AgNPs (50:50 in mass ratio) or Ag(+) ions, all at the total Ag concentration of 5mg/L. In a binary (bacteria-phages) system where the E. coli host was exposed to MS2 and nanoparticles simultaneously, the dynamic changes of active bacteria and MS2 phages during incubation demonstrated that exposure of AgNPs (5mg/L Ag) and ZnO NPs (20mg/L ZnO) increased the number of phages by 2-6 orders of magnitude. These results suggested that exposure of nanoparticles could greatly facilitate bacterial viruses like MS2 to infect the E. coli host.     

梨形核壳结构氧化锌/银亚微米球的制备、表征及光学性能

利用亚锡离子还原银离子生成的金属银沉积在合成的梨形氧化锌表面作为晶种,进一步生长银纳米粒子,制备了梨形的、核壳结构的、单分散的氧化锌/银亚微米球。利用X射线衍射、透射电镜、能量色散X射线谱、紫外可见吸收谱及光致发光谱对所制备样品的形貌、微观结构、组成和光学性能进行了表征。结果表明:(1)样品是由梨形亚微米氧化锌核和银纳米颗粒壳组成;(2)在氧化锌表面的银纳米粒子作为光激发产生的电子捕获剂提高了光产生的载流子的分离效率,在能量没有改变的情况下减少了紫外发射光的强度,淬灭了可见发射光。     

The surface modification of spherical ZnO with Ag nanoparticles: A novel agent,biogenic synthesis,catalytic and antibacterial activities

Nowadays, the industrial wastewater pollutants including toxic dyes and pathogenic microbes have caused serious environmental contaminations and human health problems. In the present study, eco-friendly and facile green synthesis of Ag modified ZnO nanoparticles (ZnO-Ag NPs) using Crataegus monogyna (C. monogyna) extract (ZnO-Ag@CME NPs) is reported. The morphology and structure of the as-biosynthesized product were characterized by field emission scanning electron microscopy (FESEM), X-Ray diffraction (XRD), differential reflectance spectroscopy (DRS), dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDS) techniques. TEM and FESEM images confirmed the oval and spherical-like structure of the products with a size of 55–70 nm. The EDS analysis confirmed the presence of Zn, Ag, and O elements in the biosynthesized product. The photocatalytic results showed ZnO-Ag@CME NPs were degraded (89.8% and 75.3%) and (94.2% and 84.7%) of methyl orange (MO) and basic violet 10 (BV10), under UV and sunlight irradiations, respectively. The Ag modified ZnO nanoparticles exhibited enhanced catalytic activity towards organic pollutants, and showed better performance than the pure ZnO nanoparticles under UV and sunlight irradiations. This performance was probably due to the presence of silver nanoparticles as a plasmonic material. Antibacterial activity was performed against different bacteria. ZnO-Ag@CME NPs showed high antibacterial activity against K. pneumoniae, S. typhimurium, P. vulgaris, S. mitis, and S. faecalis with MIC values of 50, 12.5, 12.5, 12.5, and 12.45 µg/mL, respectively. All in all, the present investigation suggests a promising method to achieve high-efficiency antibacterial and catalytic performance.     

Study on luminescence characteristic of the ZnO/polymer hybrid films

The cyclohexane solution of PS (polystyrene) and the ethyl acetate solution of PMMA (polymethyl methacrylate) were used as flowing liquid; the ZnO/polymer hybrid colloids were successively produced by focused pulsed laser ablation of ZnO target in interface of solid and flowing liquid. As solvent in the hybrid colloids has volatized, the ZnO/polymer hybrid films were obtained. The hybrid colloids were characterized by high-resolution transmission electron microscopy (HRTEM) and select-area electron diffraction (SEAD). The results show a good dispersion of the ZnO nanoparticles in the polymer matrix. The hybrid films were characterized by fluorescence spectrum, Fourier transform infrared spectroscopy (FTIR) spectroscopy, thermogravimetry with FTIR (TG/FTIR), and X-ray photoelectron spectrum. The results show the ZnO/polymer hybrid films can radiate strong blue light under ultraviolet. Meanwhile, the ZnO/polymer hybrid films have higher chemical stability than ZnO nanoparticles because nano-ZnO nanoparticles were enwrapped by polymers. In addition, the ZnO hybrid films have higher thermal stability then the related pure polymers because of strong interaction among ZnO nanoparticles and polymers.     

Synthesis, characterization and antimicrobial investigation of mechanochemically processed silver doped ZnO nanoparticles

The application of nanomaterials has gained considerable momentum in various fields in recent years due to their high reactivity, excellent surface properties and quantum effects in the nanometer range. The properties of zinc oxide (ZnO) vary with its crystallite size or particle size and often nanocrystalline ZnO is seen to exhibit superior physical and chemical properties due to their higher surface area and modified electronic structure. ZnO nanoparticles are reported to exhibit strong bacterial inhibiting activity and silver (Ag) has been extensively used for its antimicrobial properties since ages. In this study, Ag doped ZnO nanoparticles were synthesized by mechanochemical processing in a high energy ball mill and investigated for antimicrobial activity. The nanocrystalline nature of zinc oxide was established by X-ray diffraction (XRD) studies. It is seen from the XRD data obtained from the samples, that crystallite size of the zinc oxide nanoparticles is seen to decrease with increasing Ag addition. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) data also supported the nanoparticle formation during the synthesis. The doped nanoparticles were subjected to antimicrobial investigation and found that both increase in Ag content and decrease in particle size contributed significantly towards antimicrobial efficiency. It was also observed that Ag doped ZnO nanoparticles possess enhanced antimicrobial potential than that of virgin ZnO against the studied microorganisms of Escherichia coli and Staphylococcus aureus.     

Dual Ag/ZnO‐Decorated Micro‐/Nanoporous Sulfonated Polyetheretherketone with Superior Antibacterial Capability and Biocompatibility via Layer‐by‐Layer Self‐Assembly Strategy

Polyetheretherketone is attractive for dental and orthopedic applications due to its mechanical attributes close to that of human bone; however, the lack of antibacterial capability and bioactivity of polyetheretherketone has substantially impeded its clinical applications. Here, a dual therapy implant coating is developed on the 3D micro‐/nanoporous sulfonated polyetheretherketone via layer‐by‐layer self‐assembly of Ag ions and Zn ions. Material characterization studies have indicated that nanoparticles consisting of elemental Ag and ZnO are uniformly incorporated on the porous sulfonated polyetheretherketone surface. The antibacterial assays demonstrate that Ag‐decorated sulfonated polyetheretherketone and Ag/ZnO‐codecorated sulfonated polyetheretherketone effectively inhibit the reproduction of Gram‐negative and Gram‐positive bacteria. Owing to the coordination of micro‐/nanoscale topological cues and Zn induction, the Ag/ZnO‐codecorated sulfonated polyetheretherketone substrates are found to enhance biocompatibility (cell viability, spreading, and proliferation), and hasten osteodifferentiation and ‐maturation (alkaline phosphate activity (ALP) production, and osteogenesis‐related genetic expression), compared with the Ag‐decorated sulfonated polyetheretherketone and the ZnO‐decorated sulfonated polyetheretherketone counterparts. The dual therapy Ag/ZnO‐codecorated sulfonated polyetheretherketone has an appealing bacteriostatic performance and osteogenic differentiation potential, showing great potential for dental and orthopedic implants.