1,137 research outputs found

    Large Area Perovskite Solar Cells with High Short-circuit Current Density Based on Tantalum-Doped TiO2 Nanorods

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    本组前期工作实现了目前基于二氧化钛纳米棒钙钛矿太阳能电池的最高效率。本文基于该电池结构,对二氧化钛纳米棒进行掺杂改性,进一步提高了电池的短路电流;并将钙钛矿层的制备方式由一步旋涂法变为两步旋涂法,提高了钙钛矿成膜的均一性;最后将其应用1x1cm2的大面积太阳能电池中,取得了最高为13.11%的电池效率。 首先完成了对二氧化钛纳米棒的Ta掺杂,并探讨了Ta掺杂对二氧化钛能级位置的影响。由于二氧化钛纳米棒的形貌会对电池效率产生影响,通过调控Ta掺杂浓度,及不同掺杂浓度相应的水热反应时间,确保了掺杂前后二氧化钛纳米棒的形貌一致性。研究结果表明在Ta5+5d轨道与氧空位的协同作用下,随着掺杂浓度的增...Our group has reported the highest efficiency of perovskite solar cells based on TiO2 nanorods. In this paper, based on this structure, we modified TiO2 nanorods by doping Ta to improve the short current of solar cells, and we also changed the preparation method of perovskite from one-step spin coating to two-step spin coating, and achieved the best efficiency of 13.11% in 1x1 cm2 active area. F...学位:工学硕士院系专业:萨本栋微米纳米科学技术研究院_光伏工程学号:3352014115242

    Controllable Synthesis of Co-based Nanocrystals and Their Catalytic and Electrochemical Properties

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    应用于新能源领域的新型非贵金属纳米材料是当今科学界的关注热点之一,钴基纳米材料是特别重要的一类。钴基纳米材料在催化、传感器、锂离子电池、磁性材料等方面有非常广泛的应用。本文选用高温有机相热解法,合成了八面体、球形、六边形片状和棒状氧化钴纳米晶,钴基磷化物纳米棒,金钴合金纳米粒子和磷化钴纳米棒/石墨烯复合材料。合成中采用了一锅法,前驱体快速注入和注射泵缓慢注入等方法来控制合成纳米晶的形貌、成分和相组成。对合成的钴基纳米晶,进行了催化产氢和锂离子电池负极方面的应用探索。并探讨了影响性能的相关机制。主要的研究结果如下。 制备出不同形状的立方相和六方相的CoO纳米晶,其在催化水解硼氢化钠产氢反应中,...Nowadays, many researches have achieved important progresses in the development of non-noble metal nanocrystals and their alloys with high performance in the field of new energy. Cobalt-based nanomaterials are an important group among them. Some cobalt-based nanomaterials have demonstrated excellent properties as catalysts, sensors, lithium ion batteries and magnetic materials. This dissertation m...学位:工学博士院系专业:材料学院_材料物理与化学学号:2072011015348

    Study on controllable self-assembly of Au nanorods and their application in biological detection

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    金纳米棒因其特有的物理、化学、光学性能,被广泛应用于细胞成像、光热治疗、生物传感器等各个领域。目前,金纳米棒的有序化组装已经成为新的研究热点,利用静电作用、DNA杂交、抗原抗体反应等方法可将金纳米棒组装成头对头、肩并肩等不同结构。组装后的金纳米棒由于粒子间的耦合效应表现出独特的集体性质,从而产生新颖的物理、化学性能。其中,金纳米棒组装体引起的局域电场增强可用于表面增强拉曼散射(SERS)技术中,使拉曼信号产生数量级的放大,从而达到灵敏检测的目的。然而,金纳米棒自组装仍然存在许多问题,诸如组装形态、稳定性等都制约着组装技术的实际应用。据此,本文围绕金纳米棒组装体展开研究,探讨了静电吸引、生物识别...Au nanorods (AuNRs) have attracted special interest because of their unique chemical, geometrical and optical properties. AuNRs can be used in many biomedical applications such as cell imaging, photothermal therapy, bioassay and biosensor. So far, several strategies including electrical interaction, biotin-streptavidin connectors, antibody-antigen recognition, and DNA hybridization have been devel...学位:理学硕士院系专业:材料学院_生物医学工程学号:3142012115007

    Au and Ag Nanoparticles: Synthesis, Assembling and Their SERS Applications

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    广泛地说,所有直径在纳米级别的粒子(杂化纳米粒子,核壳纳米粒子等)都称之为纳米粒子。由于贵金属粒子稳定性好,易合成以及光学特性等优点,因此合成贵金属纳米粒子仍然是探针研究中最受欢迎的一部分。同时,银和金在可见光和近红外区域能够提供很强的光学信号,使得它们成为最受欢迎的贵金属粒子。在最近的工作中,合成纳米粒子的三个主要挑战分别是:(1)如何在硅基底上获得大范围的单层纳米粒子;(2)如何合成高产率的金纳米棒;(3)如何在金纳米棒外包裹上银壳。为了克服上述难题,我们做出很多的努力,并且取得了重要突破和结果。 在第三章中,我们利用两相法成功地将银立方体单层组装在了硅基底上。首先往银立方体中加入超纯水...Broadly speaking, the term nanoparticle encompasses any and all types of particles (hybrid nanoparticles, core-shell nanoparticles, etc.) with a diameter on the nanoscales. Synthesis noble metal nanoparticles stand apart as the most popular group of probes. The Nobel metals have retained their preminces amongst researchers due to their stability, ease synthesis, and optical properties. Silver and ...学位:理学硕士院系专业:化学化工学院_物理化学学号:2042015115470

    Oxidative Clorination of Methane over CeO2 Nanorod Supported Palladium Oxide And Manganese Oxide Catalysts

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    本学位论文主要针对以氧化钯和氧化锰修饰的二氧化铈纳米棒为催化剂的甲烷氯氧化催化体系开展了深入研究。并从催化剂性能、结构特征以及反应机理等方面进行探讨。 CeO2纳米棒是甲烷氯氧化制一氯甲烷的有效催化剂。对CeO2纳米棒的修饰可以进一步提高其催化性能,其中经贵金属Pd修饰制备的Pd/CeO2纳米棒可以显著提高CH3Cl选择性,而经Pd及MnOx共同修饰制备的Mn-Pd/CeO2纳米棒可以在保持较高的CH3Cl选择性的前提下提高CH4转化率。在10Mn-1Pd/CeO2纳米棒上甲烷转化率为33%时,CH3Cl选择性保持在72%。且经过100h寿命测试,该催化剂上甲烷转化率稳定在31%,可获得74...This dissertation contributes to the studies on the oxidative chlorination of methane catalysed by CeO2 nanorods modified with Pd and MnOx. Structure and catalytic performances of catalysts for this reactions have been investigated in detail. Reaction mechanism were also studied. CeO2 nanorods was an excellent catalyst for oxidative chlorination of CH4. Pd/CeO2 nanorods prepared by the modif...学位:理学硕士院系专业:化学化工学院_物理化学(含化学物理)学号:2052010115160

    Hydrothermal Synthesis of CdS Nanorods in NaOH Solution and their photocatalytic properties

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    CdS是一种重要的Ⅱ-Ⅵ族半导体材料,室温下其禁带宽度为2.42eV,表现出良好的光学性质和光电特性,被广泛应用于光、电、磁、催化等领域。众多形貌的CdS纳米材料中,纳米线、纳米棒、纳米管等一维纳米材料因在纳米器件、太阳能电池、光催化方面具有巨大的应用潜力而备受关注,其控制合成也成为研究热点。作为一种可见光光催化剂,一维CdS纳米材料的光催化活性和光稳定性还有待于进一步提高,寻找适当的方法来改善其光催化性能是该领域的一项重要研究内容。 本文对NaOH溶液介质中水热合成CdS纳米棒进行了系统的研究,探讨了多种反应条件对一维CdS纳米棒形貌和晶体结构的影响,提出了可能的生长机理,为一维CdS纳米...As an important II-VI group semiconductor with a narrow band gap of 2.42 eV , CdS exhibits good optical and optoelectronic properties, and is widely used in optics, electricity, magnetism and catalysis. Among various CdS nanomaterials, one dimensional (1D) CdS nanomaterials, such as nanowires, nanorods, nanotubes, have attracted much attention due to their huge potential applications in nanodevice...学位:理学硕士院系专业:化学化工学院_分析化学学号:2052009115132

    A DDA Calculation on the Optical Properties of Silver Nanorods

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    【中文文摘】利用离散偶极近似 (Discretedipoleapproximation ,简称DDA)的方法 ,从理论上对粒子的形状、尺寸及周围介质等因素对银纳米粒子 ,特别是银纳米棒的光学性质的影响进行了较系统的研究 .计算表明 ,置于空气中的棒状银纳米粒子的光学性质与其形状密切相关 ,纵向表面等离子体共振吸收峰的位置随纳米棒长径比的增加呈现线性红移关系 .给出了空气中银纳米棒纵向表面等离子体共振吸收峰的位置随长径比变化的DDA拟合公式 .如果将金属纳米粒子置于折射率更高的介电环境中 ,其纵向等离子体共振吸收峰的位置进一步呈现线性红移关系 .合成的银纳米粒子的TEM图像及相关的UV VIS消光光谱显示DDA计算结果与实验值相当一致 .DDA算法与Mie′s理论在计算球状银纳米粒子的消光系数时给出很接近的结果 ,这表明用DDA的方法来分析银的光学性质是准确可靠的 ;而DDA算法对银纳米棒消光特性的成功拟合则表明 ,该算法相对Gans′理论而言 ,在研究纳米粒子的光学性质时具有更广的适用性及更高的准确性 . 【英文文摘】The optical properties of metal nanoparticles are quite different from those of the bulk materials mainly due to the collective oscillations of their conduction electrons known as the surface plasmon resonance (SPR), which is strongly dependent on the particle shape and size, and the dielectric properties of the local environment where the nanoparticles are embedded in. Based on the discrete dipole approximation (DDA) method, we studied the optical properties of silver nanorods with different aspect ratios ...Project supported by the National Natural Science Foundation of China (2 0 2 2 80 2 0,2 0 0 2 10 0 2

    Preparation and Evaluation of HCPT-loaded, Targeted Nanorods Induced by pH Switch

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    目前,在大部分给药纳米粒子制备方法中,疏水基团是必需的,因此这些制备方法都非常依赖于有机溶剂。而这些有机溶剂通过减压蒸馏或者冻干等传统方法是无法完全除去的,即使是透析也无法完全去除包裹在纳米粒子之内的残留溶剂,这样在纳米粒子内就会不可避免的存在残留有机溶剂。残留溶剂不仅对人体的健康有害,而且会加速药物制剂的变质失效。因此,如何减少或去除药物制剂中的残留溶剂一直是人们关注的问题。 羟基喜树碱(HCPT)和甲氨喋呤(MTX)都是临床常用的抗肿瘤药物,二者作用机制不同,羟基喜树碱是通过作用于DNA拓扑异构酶I来抑制DNA复制、转录和有丝分裂,而甲氨喋呤则是通过与二氢叶酸还原酶结合,干扰辅酶F的合成...Since the hydrophobic group is essential to the synthesis of the drug-loaded nanoparticles, a majority of the methods rely heavily on organic solvents. These organic solvents might be residual within the particles and could not be completely removed by conventional methods, such as reduced pressure distillation or freeze drying. As a result, trace of organic solvents would remain in the medicine, ...学位:理学博士院系专业:化学化工学院_纳米材料化学学号:2052013015388

    Photogenerated Cathodic Protection Properties Based on Micro-nano ZnO/TiO2 Composite Films

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    金属腐蚀问题给人们生活带来不便,且造成巨大的经济损失。传统金属防腐蚀方法均存在一定的缺陷。因此开发低能耗、环境友好型的金属防腐蚀技术具有重要的科研及应用意义。基于微纳米ZnO、TiO2优异光电化学性能的新型防腐技术--光生阴极保护技术已引起人们的广泛关注。但ZnO、TiO2只能吸收紫外光,光生载流子易复合,且暗态下难以持续对金属进行阴极保护。因此,本文采用工艺操作简便、常压低温条件下的湿化学方法制备ZnO阵列及对其进行TiO2、Fe-TiO2复合薄膜修饰耦合,并通过光电化学测试技术研究微纳结构复合阵列薄膜光阳极对304不锈钢的光生阴极保护性能。主要研究内容及结果如下: 1. 采用电化学沉积技...Metal corrosion problems bring inconvenience to people's life, and also can cause huge economic losses. All the traditional methods of anti-corrosion for metal have some defects. Therefore, the development of low energy consumption, environment-friendly anti-corrosion technology for metals has important scientific and practical application significance. Based on the excellent photoelectric chemica...学位:工学博士院系专业:材料学院_材料物理与化学学号:2072011015348

    不同形貌普鲁士蓝纳米粒子的合成及光热性能

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    制备了立方体、直角立方体、球形、棒状、中空状、核壳状、梭形、多面体等8种不同形貌的普鲁士蓝纳米粒子,利用扫描电子显微镜、透射电子显微镜、紫外-可见分光光度计等对纳米粒子进行了表征,考察了普鲁士蓝纳米粒子光热性能的影响因素.结果表明,普鲁士蓝纳米粒子的形貌与光热性能之间联系密切,粒子形貌不同,光热性能不同;当外部实验条件一定时,纳米粒子的形貌、大小、吸收横截面积、尖锐化程度及密实程度等对其光热性能有很大的影响;当纳米粒子形貌一定时,外部因素如激光器的选择、激光功率密度及纳米粒子的浓度等直接影响普鲁士蓝纳米粒子的光热性能;在相同浓度下,激光功率密度越大,纳米粒子的升温效果越明显,光热性能越好;而激光功率密度不变时,纳米粒子浓度越大,其光热转换效率越高.国家自然科学基金(批准号:31271071,31371012,U1505228)资助~
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