Semiconductor nanowires, such as group IV and III-V nanowires, shows distinct electrical, optical and mechanical properties from their bulk counterparts due to their nanoscale size and 1-D morphology. For example, the quantum confinement effect modulates the band gap of a semiconductor nanowire when its diameter approaches or below the exciton...
Connecting structure and function in nanoscale engineered materials and devices relies on the analysis of the fundamental arrangement of matter, frequently under dynamic conditions. The demand to image structures at fundamental length scales has touched inorganic materials, biology, and frequently hybrid hard/soft materials with unique phenomena driven by heterogeneous components....
Colloidal crystal engineering with DNA offers new opportunities for materials scientists to build and program the structures of superlattices beyond what can be accomplished in Nature with atomic crystal lattices. Thus far, such materials primarily have been studied for their optical properties due to the insulating nature of the DNA...
Rationally assembled nanostructures exhibit distinct physical and chemical properties beyond their individual units. The development of nanofabrication tools enables precise structural defining of nanomaterials scalable to large areas. This dissertation focuses on plasmonic nanoparticle arrays that show unique diffractive coupling with lattice spacings engineered close to the wavelength of light....
This thesis describes a series of fundamental studies that address the role of electrostatic interactions in modulating i) the permeability of the ligand shell of a colloidal quantum dot (QD) to an anionic redox probe; ii) the resulting yield of photoinduced electron exchange within the QD ‒ redox probe complex;...
Multimetallic nanoparticles represent an important class of electrocatalysts which are critical for many energy and environmental applications including fuel cells, hydrogen production, and greenhouse gas elimination. The properties of these nanoparticles depend on their composition, size, shape, and structure. Therefore, developing new strategies which provide a high level of control...
As demonstrated by efforts in graphene commercialization, scalable synthesis and high-quality material availability are primary limiting factors for the realization of technologies based on two-dimensional (2D) materials. Thus, in considering the fate of emergent 2D materials such as the metal chalcogenides, the challenge of scalable synthesis is a highly relevant...
The advancement of nanotechnology is at least partially dependent on the ability to synthesize and arrange complex nanostructures on a substrate. Nanolithography, or the patterning of materials at the sub-micrometer length-scale, has been traditionally performed using a number of methods such as conventional photolithography, ion-beam etching, and electron-beam lithography. While...
Non-planar and curved architectures of otherwise flat 2D materials present an important paradigm for nanoscale analysis and design of emergent material properties. Atomically-thin transition metal dichalcogenides (TMDs) have emerged at the forefront of the 2D materials field in recent years largely due to their attractive and tunable chemical, optical, and...
Mixed-dimensional heterojunctions between two-dimensional (2D) materials and organic semiconductors is a rapidly growing field. This is motivated by the promise of leveraging the extraordinary properties of 2D materials with the synthetic tunability and reconfigurability of organic electronics, allowing the realization of new physics or devices that are not possible in...