Surfaces that are nanopatterned, metallic, and magnetic can support surface plasmon resonances, providing an alternative and effective way to reconfigure flat optical components. Utilising a range of near- and far-field characterisation techniques, the optical and magneto-optical properties of lithographically patterned thin magnetic films are investigated. A magneto-optical diffractometer was designed, assembled, and commissioned to characterise periodic magneto-plasmonic nanostructures. For Ni and Co nanostructured antidot arrays, enhanced values of the magneto-optical Kerr rotation were recorded for energies and angles corresponding to excitations of surface plasmon polaritons. This enhancement was found to be thickness dependent. Modification of the optical properties via applied transverse magnetic fields and the excitation of surface plasmon polaritons, was demonstrated for an antidot array of pure Ni. The excitation was also shown to enhance the generation of second harmonics, as well as further activate nonlinear-optical mechanisms. In order to fully resolve and explain the source of this remarkable magneto-optical activity, near field probing techniques were used. This allows for mapping the electric near-field with a sub-wavelength resolution, thereby revealing the interplay between the light and the nanostructured lattice. The measurements show that the electric near field intensification, induced by plasmon excitation, increases the polarisation conversion, which correlates to the observed magneto-optical Kerr rotation.

Thesis advisor: Krzysztof Kempa / Nonlocal effects, the wavenumber dependence in a medium's response to external disturbance, is treated in this thesis. Numerical computation methods to include nonlocal effects in plasmonic nanostructures’ electromagnetic response are discussed, and applications of plasmonics to a few other fields are elaborated. First, a computation scheme is proposed to extend conventional finite-difference time-domain (FDTD) methods to nonlocal domain. An effective film whose response is derived from Feibelman's d-function formalism is to replace the highly non-uniform metal surfaces in simulations. It successfully produces numerical results of plasmonic resonance shift and field enhancement which agrees with the experimental data to first order. This scheme is still classical, thus very fast compared to the other first principle quantum methods such as density functional theory. Then electron's scattering rate in an effective medium with plasmonic nanostructures embedded-in, in random phase approximation, is developed, with the wavenumber dependence in the medium’s response accounted. Utilizing this calculation scheme of electron’s scattering rate, further specific applications are following. We show by simulation of the plasmonic nanostructures and calculation of the electron scattering rates that hot-electron plasmon-protection (HELPP) effects can protect the extra energy of hot electrons from being dissipated as heat. This can be a prototype of the 3rd generation solar cells. In another application, we investigate the electron polar-optical-phonon (POP) scattering in heavily-doped semiconductors when plasmonic nanostructures are embedded-in. We show that electron-POP scattering can be significantly suppressed compared to that of bulk semiconductors. In the third application, we propose the plasmonic multiple exciton generation (PMEG) scheme, with simulations and calculations, showing that the efficiency of multiple exciton generation in conventional semiconductors could be enhanced significantly with proper designed plasmonic nanostructures embedded-in or attached-adjacent. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

A Dissertation submitted to the Faculty of Science, School of Chemistry, University of Witwatersrand in fulfillment of the requirements for the degree of Master of Science. Johannesburg 2014 / The resin-gel method of synthesis successfully produced compounds of mixed metal oxides of copper titanium oxide powders of the form CuxTiyOZ with different compositions. These include Cu3TiO5, Cu3TiO4, Ti3Cu3O, Cu2Ti4O, Cu2Ti2O5 and Cu2TiO3. Heat-treatment of the powders at 300°C, 500°C, 700°C and 900°C for 1 hour was performed to determine the full composition/temperature phase diagram. The target particle size was in the 10- nanometer range, and for most of the samples, this size was achieved. Powder xray diffraction and transmission electron microscopy were the main techniques used to study the crystallization of these materials and their transformation to other polymorphic phases under different temperatures. Phase-match, particle size analysis and TEM imaging determined the properties and characteristics of the respective crystallographic phases of these materials. TEM analysis showed that some powders agglomerated while others exhibited both regular and irregular morphologies and polydisperse particle size distribution. Only a single unique phase was identified, but its structure could not be determined.

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. / A comprehensive experimental study on alternating current (AC) electrical transport in the three forms of carbon nanotubes (CNTs) and nanodiamond films is presented. It is termed dynamic electrical transport to differentiate it from direct current measurements, which may be referred as static transport. The results and analysis are based on the scattering parameter measurements of a few horizontally aligned single, double, multi-walled carbon nanotubes and nanodiamond films. Which were measured in the frequency range 10 MHz to 65 GHz, at room and cryogenic temperatures using a vector network analyser. The work is motivated by the fact that AC transport in 1D systems has not been fully studied and is not well understood. From direct current measurements, it is known that one dimensional (1D) electrical transport is very different from its two or three dimensional counterpart. This is because adding an electron to a 1D system tends to affect the whole system in ways which to date cannot be fully explained theoretically. CNTs present an ideal platform to study the AC or dynamic transport behaviour of 1D systems because of the high mobility and electrical conductivity at nano-scale. Therefore from the AC complex impedance and conductance, this work demonstrates quantum effects of collectively excited strongly interacting electrons (Luttinger Liquid), which had been predicted theoretically but not observed experimentally using this technique. Ballistic transport at room temperature is also demonstrated by setting the stimulus frequency higher than the scattering rate in the CNTs. A crossover from capacitive to inductive behaviour in the imaginary component of impedance has been shown by improving the CNT-electrode coupling. Furthermore the effect of metal contacts on microwave/ radio frequency transmission is also demonstrated. The results are consolidated by RF simulations, as strong conclusions are drawn. Studies on the dynamic transport in nanodiamond films revealed a crossover from the insulating to semi-metallic regime by nitrogen incorporation. The crossover is explained by considering the changes of the grain boundary morphology. This work shows that AC transport in polycrystalline nanodiamond films is similar to DC transport.

M.Sc., Faculty of Science, University of the Witwatersrand, 2011 / In this dissertation, the synthesis of nitrogen doped carbon nanotubes (N-CNTs) was performed successfully, using a floating catalyst chemical vapour deposition (CVD) method. Fe(CO)5 was utilized as the catalyst and acetonitrile and toluene as nitrogen and carbon sources respectively. Two different procedures were used to add reagents to the reactor: an injection method and a bubbling method. The effect of nitrogen concentration and physical parameters such as reaction temperature, gas flow rate on the morphology, crystallinity and thermal stability of the tubes was studied. The synthesized materials were characterized by means of Raman spectroscopy, TGA and TEM analyses. The presence of nitrogen was confirmed by the presence of the bamboo formations in the tubes by TEM. A comparison of the data from the numerous reactions revealed that N-CNTs can be made from Fe(CO)5 and acetonitrile. Further the main conclusions achieved using the injection method were: i) the maximum number of tubes with bamboo structure were made using on acetonitrile concentration of 15%, ii) The best growth temperature to make N-CNTs was 850 oC, iii) An increase in acetonitrile concentration decreased the yield of NCNTs and iv) Tubes with the narrowest outer diameters were made using an acetonitrile concentration of 15%.

A plasmônica é a área que faz a junção entre fotônica e nanoestruturas. As implicações tecnológicas resultantes do acoplamento entre campos eletromagnéticos e oscilações eletrônicas em um material condutor fazem desta área uma das mais excitantes da óptica atualmente. Neste contexto, o objetivo deste trabalho é o projeto, fabricação e caracterização de nanoestruturas metálicas visando aplicações em óptica difrativa, incluindo filtros e lentes. Inicialmente, uma extensa revisão bibliográfica permitiu definir quais tipos de estruturas seriam abordadas, levando em conta tanto a capacidade computacional para fazer a modelagem numérica quanto a infraestrutura necessária na fabricação dos elementos. A primeira estrutura analisada foi um filtro óptico baseado em ressonância de modo guiado e ressonância plasmônica. Foram projetados e fabricados três filtros operando no azul, verde e vermelho. Resultados experimentais mostraram eficiência acima de 80% e largura de banda em torno de 20 nm, consideravelmente menor que os ~60 nm obtidos previamente na literatura considerando estrutura semelhante. Foi possível verificar as cores puras associadas à ressonância de modo guiado. Além disso, foi demonstrado como gerar as três cores primárias - azul, verde e vermelho - usando apenas o filtro vermelho. A segunda estrutura proposta consiste em uma lente tipo zonas de Fresnel integrada com um filme metálico. Resultados numéricos identificaram uma estrutura ressonante do tipo Fabry-Perot que possibilita uma redução dos lóbulos laterais gerada pela lente por um fator 3.0 na polarização TM e 4.8 na polarização TE. A estrutura foi fabricada usando litografia por nanoimpressão. Por fim, a terceira estrutura analisada foi um holograma binário baseado em metassuperfície, cuja célula básica é composta de um ressoador tipo nanorod. Foi proposta uma geometria na qual a diferença de fase entre os elementos é igual a π independente do comprimento de onda. Assim, o holograma pode operar em uma faixa espectral definida pela largura de banda transmitida. É descrito o inicio da fabricação do elemento usando litografia por feixe de elétrons. / Plasmonics is a field of study that merge photonics and nanostructures. The advanced technological implications makes it one of the most exciting field in Optics in current days. Therefore the objective of this study is the design and fabrication of metallic nanostructures aiming at applications in diffractive optics. Firstly, an extensive literature review allowed to define what types of structures would be addressed, taking into account both software simulations and the require infrastructure for the elements\' fabrication. The first analyzed structure was an optical color filter based on guided mode resonance and surface plasmon resonance. Three filters, operating in blue, green and red, were designed and fabricated using interferometric lithography. Experimental results show above 80% efficiency and ~20 nm bandwidth, which is significantly smaller than ~60 nm previously obtained in the literature with similar structures. It was possible to show the pure colors associated with the modal resonance. Furthermore, it was shown how to obtain the primary red, blue, and green colors using only the red filter. The second structure proposed consists of Fresnel zones plates integrated with a metallic film. Numerical results show a resonant structure which enables side lobe reduction by a factor 3.0 in the TM polarization and 4.8 in the TE polarization. This structure was fabricated using nanoimprint lithography. The third analyzed structure was a binary hologram based on metasurface whose basic cell is composed of a nanorod metallic resonator. The phase difference between two elements is equal to π, regardless of the wavelength; thus, the hologram operates in a spectral band defined by transmitted bandwidth. The first steps of its fabrication process using electron beam lithography are presented and described.

O interesse por aplicações que utilizam efeitos de plásmons poláritons de superfície (SPP) vem crescendo, pois as ondas SPPs apresentam enorme potencial no desenvolvimento de filtros e biossensores ópticos. A sensibilidade da ressonância de plásmons em nanoestruturas permite o estudo em tempo real de variações mínimas em índice de refração, solutos e antígenos. Neste trabalho foram aplicadas técnicas de nanofabricação (litografia por feixe de elétrons e íons) para o desenvolvimento de estruturas plasmônicas e sua posterior caracterização. As estruturas foram utilizadas para verificar propriedades de absorção e fluorescência em moléculas opticamente ativas - Porfirina e Rodamina 6G. As estruturas - conjuntos de fendas e matrizes de buracos circulares com diversos períodos - foram fabricadas em um filme fino de ouro (Au) sobre substrato de vidro (Borofloat 33 - Schott), usando um feixe de íons de Gálio (FEI Quanta Quanta 3D 200i). A transmissão óptica foi estudada na região de 400nm a 900nm (VIS-NIR). Os resultados experimentais foram comparados com simulações computacionais. O estudo da absorção molecular da porfirina foi conduzido observando-se a variação na intensidade da transmissão. Ao alterar a concentração da porfirina sobre as estruturas, foi possível caracterizar a curva de absortividade ε(λ) da porfirina para concentrações entre 100 μg/ml e 500 μg/ml em quantidades mínimas de analito (20 μl). A técnica de microscopia confocal foi empregada no estudo da fluorescência da Rodamina 6G diluída num filme fino de PMMA sobre as estruturas. Ao avaliar a fluorescência da Rodamina 6G na reflexão das estruturas, observou-se o efeito de quenching devido a emissão de plásmons. Os resultados obtidos poderão ser utilizados de apoio a trabalhos futuros, desenvolvidos em plasmônica aplicada a biossensores. / The interest in applications that use the effects of surface plasmon polaritons (SPP) has been increasing. SPPs waves have an enormous potential for the construction of optical filters and biosensors. The sensitivity of plasmon resonance in nano-structures allows studying in real-time minimal variations in the refractive index, solutes and antigens. In this work, we have studied nanofabrication techniques (electron and ion beam lithography) and the characterization of plasmonic structures. Plasmonic effects were used as biosensors of absorption and fluorescence in optically active molecules - Porphyrin and Rhodamine 6G. The structures - sets of slits and arrays of circular holes with different periods - were manufactured in gold (Au) thin film on a glass substrate (Borofloat 33 - Schott) using a galium ion beam equipment (FIB FEI Quanta Quanta 3D 200i). Optical transmission was studied in the region of 400 nm to 900 nm (VIS-NIR). The characterization of structures was realized used the Ocean Optics USB-2000 spectrometer. The experimental results were compared to computer simulations. The study of molecular absorption of porphyrin was conducted by observing the variation in intensity of transmission. By changing the porphyrin concentration in the structures, it was possible to characterize the porphyrin absorptivity curve ε(λ) in concentrations between 100 μg/ml and 500 μg/ml in minimum amounts of analyte (20 μl). Confocal microscopy was used to study the fluorescence of Rhodamine 6G on plasmonic structures. The plasmon quenching effect was observed in the evaluation of the fluorescence of Rhodamine 6G in the reflection of the structures. The results will support future works linking plasmonics and biosensors.

by Li, Tsui Kiu = 納米鋁酸鋰網絡增強的鋁基複合材料的製造和表徵 / 李翠翹. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / by Li, Tsui Kiu = Na mi lü suan li wang luo zeng qiang de lü ji fu he cai liao de zhi zao he biao zheng / Li Cuiqiao. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Table of contents --- p.vi / List of tables --- p.ix / List of figures --- p.xii / Chapter Chapter 1. --- Introduction / Chapter 1.1. --- Metal matrix composites (MMCs) --- p.1-2 / Chapter 1.1.1. --- Introduction --- p.1-2 / Chapter 1.1.2. --- Aluminum-based metal matrix composites (Al-MMCs) --- p.1-2 / Chapter 1.1.3. --- Applications of MMCs --- p.1-3 / Chapter 1.1.3.1. --- Automotive applications --- p.1-3 / Chapter 1.1.3.2. --- Aerospace applications --- p.1-4 / Chapter 1.1.4. --- Fabrication methods of metal matrix composites --- p.1-5 / Chapter 1.1.4.1. --- Stir casting --- p.1-5 / Chapter 1.1.4.2. --- Liquid metal infiltration --- p.1-5 / Chapter 1.1.4.3. --- Powder metallurgy --- p.1-6 / Chapter 1.1.4.4. --- The ex-situ sintering method --- p.6 / Chapter 1.1.4.5. --- The in-situ sintering method --- p.1-7 / Chapter 1.2. --- The Al-γ-LiA102 MMC --- p.1-7 / Chapter 1.2.1. --- Lithium aluminate (LiA102) --- p.1-8 / Chapter 1.2.2. --- Applications ofγ-LiA102 --- p.1-8 / Chapter 1.2.2.1. --- Ceramic matrices in molten carbonate fuel cell (MCFC) --- p.1-8 / Chapter 1.2.2.2. --- Tritium breeder materials in nuclear fusion reactors --- p.1-9 / Chapter 1.2.3. --- Fabrication methods ofγ-LiA102 --- p.1-10 / Chapter 1.2.3.1. --- Solid state reaction methods --- p.1-10 / Chapter 1.2.3.2. --- Sol-gel methods --- p.1-11 / Chapter 1.2.3.3. --- Hydrothermal treatment --- p.1-13 / Chapter 1.2.3.4. --- Ultrasonic Spray Pyrolysis --- p.1-13 / Chapter 1.2.3.5. --- The templated wet-chemical process --- p.1-13 / Chapter 1.2.3.6. --- Tape-casting --- p.1-14 / Chapter 1.2.3.7. --- Combustion Synthesis --- p.1-14 / Chapter 1.3. --- Previous works --- p.1-15 / Chapter 1.4. --- Current works --- p.1-16 / Chapter 1.5. --- Thesis layout --- p.1-17 / References / Chapter Chapter 2. --- Methodology and Instrumentation / Chapter 2.1. --- Introduction --- p.2-2 / Chapter 2.2. --- Powder Metallurgy --- p.2-2 / Chapter 2.3. --- Fabrication methods --- p.2-3 / Chapter 2.3.1. --- Tube furnace sintering --- p.2-3 / Chapter 2.3.2. --- Arc melting --- p.2-4 / Chapter 2.3.3. --- Annealing --- p.2-5 / Chapter 2.3.4. --- Sodium hydroxide etching --- p.2-5 / Chapter 2.4. --- Characterization methods --- p.2-6 / Chapter 2.4.1. --- Thermal analysis - Differential thermal analysis (DTA) --- p.2-6 / Chapter 2.4.2. --- Physical property analysis - Thermomechanical analyzer (TMA) --- p.2-6 / Chapter 2.4.3. --- Physical property analysis - The Archimedes' method --- p.2-7 / Chapter 2.4.4. --- Physical property analysis-Surface area and porosimetry analyzer --- p.2-8 / Chapter 2.4.5. --- Physical property analysis - Microhardness test --- p.2-9 / Chapter 2.4.6. --- Microstructural analysis - Scanning electron Microscopy (SEM) --- p.2-9 / Chapter 2.4.7. --- Surface morphology analysis - Atomic Force Microscopy (AFM) --- p.2-10 / Chapter 2.4.8. --- Phase determination - X-ray Diffractometry (XRD) --- p.2-11 / References / Chapter Chapter 3. --- Al-y-LiA102 MMC samples prepared by arc-melting / Chapter 3.1. --- Introduction --- p.3-2 / Chapter 3.2. --- Experimental details --- p.3-3 / Chapter 3.3. --- XRD analysis --- p.3-4 / Chapter 3.4. --- Microstructures --- p.3-5 / Chapter 3.5. --- NaOH etching time effects --- p.3-5 / Chapter 3.6. --- The 2-minute-etched sample --- p.3-6 / Chapter 3.7. --- Physical properties analysis --- p.3-7 / Chapter 3.7.1. --- Apparent density --- p.3-7 / Chapter 3.7.2. --- Microhardness --- p.3-7 / Chapter 3.7.3. --- BET analysis --- p.3-8 / Chapter 3.8. --- Formation mechanism ofγ-LiA102 network --- p.3-9 / Chapter 3.9. --- Effects ofLi20 contents --- p.3-10 / Chapter 3.9.1. --- Effects of Li2O contents on structure and compositions of MMCs --- p.3-10 / Chapter 3.9.2. --- Effects of Li2O- contents on coefficient of thermal expansion (CTE) --- p.3-11 / Chapter 3.10. --- Conclusions --- p.3-12 / References / Chapter Chapter 4. --- Al-y-LiAlO2 MMCs samples prepared by furnace sintering / Chapter 4.1. --- Introduction --- p.4-2 / Chapter 4.2. --- Experimental details --- p.4-2 / Chapter 4.3. --- The effects of sintering temperature --- p.4-3 / Chapter 4.3.1. --- Microstructures --- p.4-3 / Chapter 4.3.2. --- XRD analysis --- p.4-4 / Chapter 4.4. --- Prolonged NaOH etching --- p.4-5 / Chapter 4.5. --- Effects of annealing temperature --- p.4-7 / Chapter 4.6. --- DTA analysis of over-etched sample --- p.4-7 / Chapter 4.7. --- Thermal stability of the as-synthesized γ-LiA1O2 powders --- p.4-8 / Chapter 4.8. --- Conclusions --- p.4-9 / References / Chapter Chapter 5. --- Y-LiA1O2 pellets / Chapter 5.1. --- Introduction --- p.5-2 / Chapter 5.2. --- Experimental details --- p.5-2 / Chapter 5.3. --- Pellets fabricated by method 1 --- p.5-3 / Chapter 5.4. --- CTE and volume fraction of MMCs --- p.5-4 / Chapter 5.5. --- Pellets fabricated by method II --- p.5-5 / Chapter 5.6. --- Comparisons of γ-LiA1O2 fabricated by method I and method II --- p.5-6 / Chapter 5.7. --- Conclusions --- p.5-7 / References / Chapter Chapter 6. --- Conclusions and future works / Chapter 6.1. --- Conclusions --- p.6-2 / Chapter 6.2. --- Suggestions for future work --- p.6-3 / Chapter 6.2.1. --- Stability test of y-LiA1O2 in molten carbonates --- p.6-3 / Chapter 6.2.2. --- Investigation of the pore size distribution of γ-LiAIO2 network --- p.6-4 / Chapter 6.2.3. --- Fabrication of Al-γ-LiA1O2 MMC by hot isotatic pressing --- p.6-4 / Chapter 6.2.4. --- Mechanical tests --- p.6-4 / Chapter 6.2.5. --- Development of gas sensors --- p.6-5 / References

The development of nanostructured materials for environmental applications has received considerable attention in recent years. The properties of nanoparticles or nanostructured materials, such as large surface areas or high aspect ratios, translate into large improvements in the performance of existing devices and in the discovery of novel applications. On the other hand, photocatalysis is an attractive technology for the elimination of organic pollutants in water due to its simplicity, ease of implementation and reasonable cost compared to other advanced oxidation processes. A key disadvantage of many photocatalysts is their use in powder form which makes their recovery from treated water costly. In addition, incomplete removal can lead to accumulation over time with adverse effects to the environment. As a result significant effort has been placed in immobilizing photocatalytic materials on different substrates. The immobilization of photocatalyst results in a decrease in photocatalytic performance mainly due to reduction of surface area; therefore, research is now focusing on developing nanostructured materials which combine the attributes of nanotechnology and photocatalysis. In the present thesis, a systematic study of the relationship between properties of supported ZnO nanostructures and their photocatalytic activity was performed. Analysis was carried out by producing ZnO nanostructured films via anodization. The effects of voltage, temperature, reaction time and type of electrolyte on the morphology of ZnO nanostructures was studied. Results show that the type of electrolyte and its concentration determine the morphology and size of the nanostructures. Voltage, time and temperature affect the distribution and density of the nanostructures along the surface and affect the crystal size of the ZnO. The band gaps of the films were in the range of 3.27 and 3.50 eV. Although ZnO is a hydrophilic material, some of the films displayed hydrophobic and super-hydrophobic behaviour. The results obtained in this study and some data already published in the literature were correlated to the synthesis parameters, and were used to devise design guidelines to obtain ZnO films with specific nanostructures and macroscopic properties by controlling the anodization parameters. The photocatalytic activity of the ZnO nanostructured films (ZnO-NFs) were studied using three different photocatalytic reactors, (i) a thermo-stated batch reactor, (ii) a recirculating flat plate reactor, and (iii) a recirculating tubular annular reactor. Phenol and methyl orange (MO) were used as a model compounds. It was found that crystal size does not affect the photocatalytic performance of the films while morphology has an important impact on the degradation of phenol. The stability of the ZnO nanostructures was tested under different levels of oxygen, degradation of phenol occurred even at anoxic conditions following the Mars-van Krevelen mechanism. The formation of new nanostructures produced during the photocatalytic reaction was studied and a mechanism of formation was proposed. The study of the photocatalytic performance in the flat plate reactor showed that there was a mass transfer limitation in the process. ZnO nanostructures showed higher photocatalytic activity and morphology stability in the tubular annular reactor. Degradation of MO and phenol was produced in darkness by the nanostructures supported in Zn foil. It was also demonstrated that oxygen plasma post-treatment enhances the photocatalytic activity of the ZnO-NF by 36% while making the photocatalyst more stable for the photocatalytic degradation of phenol compared to those treated with heat. An electrical current was applied to the photocatalyst in the tubular annular reactor, which improved the degradation of phenol and participated in the formation of nanostructures in the Zn wire surface.

In molecular electronics, the building material (traditionally elemental semiconductor) is replaced by single molecules or a nanoscale collection of molecules. Key to molecular electronics is the ability to precisely embed molecules into a nano device/structure and to manipulate large numbers of functional devices so they can be built in parallel, with each nano-device precisely located on the electrodes. In this work, the assembly of organic and inorganic nanostructures dispersed in aqueous solutions has been controlled via chemical functionalisation. By combining this bottom-up assembly strategy with traditional top-down lithographic apporaches, the properties of these nanostructures have been investigated via a range of different techniques. The high degree of control on the molecular design through chemical synthesis and the scalability by self-assembly make this approach of interest in the field of molecular electronics. In this regard, this dissertation presents a solution-based assembly method for producing molecular transport junctions employing metallic single-walled carbon nanotubes as nanoelectrodes. On solid substrates, electrical and electronic properties have been investigated by Conducting Atomic Force Microscopy (C-AFM). Furthermore, different strategies for asymmetric junction formation have been explored towards the development of a potential nanoscale Schottky diode. Moreover, various patterning techniques based on shadow evaporation and AFM probe scratching have been investigated for the assembly of 1-D nanostructures. Nanostructures dispersed in solution were organised onto surfaces by means of dielectrophoretic assembly, and their electronic properties was then measured by the means of a probing station. In addition to the aforementioned organic nanostructures, we also report on the dispersion of boron nitride nanotubes (BNNT) by DNA wrapping, followed by the formation of nano-hybrids of boron nitride nanotubes and carbon nanotubes. Previously, researchers have adopted BNNT as a 2D dielectric layer. The work inspires me to adopt boron nitride nanotubes as 1D dielectric materials. The techniques developed in this thesis are of interest for fundamental studies of electron transport in molecules and nanostructures. Addtionally, the approaches developed in this work may facilitate the advancement of new technologies for electronics, including, but not limited to, future circuits based on single-wall carbon/boron nitride nanotubes with specific functionality.