Wee-Liat Ong

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Arrays of ligand-stabilized colloidal nanocrystals with size-tunable electronic structure are promising alternatives to single-crystal semiconductors in electronic, optoelectronic and energy-related applications. Hard/soft interfaces in these nanocrystal arrays (NCAs) create a complex and uncharted vibrational landscape for thermal energy transport that(More)
We present measurements of the thermal conductance of self-assembled monolayer (SAM) junctions formed between metal leads (Au, Ag, Pt, and Pd) with mismatched phonon spectra. The thermal conductance obtained from frequency domain thermoreflectance experiments is 65 ± 7 MW/m(2) K for matched Au-alkanedithiol-Au junctions, while the mismatched(More)
Through atomistic computational analysis of thermal transport in nanocrystal arrays (NCAs), we find that vibrational states couple elastically across the organic−inorganic interfaces with a resulting flux that depends on the ligand grafting density and the overlap between the core and ligand vibrational spectra. The modeling was performed using molecular(More)
Nanostructured Bi1-xSbx alloys constitute a convenient system to study charge transport in a nanostructured narrow-gap semiconductor with promising thermoelectric properties. In this work, we developed the colloidal synthesis of monodisperse sub-10 nm Bi1-xSbx alloy nanocrystals (NCs) with controllable size and compositions. The surface chemistry of(More)
In the search for rationally assembled functional materials, superatomic crystals (SACs) have recently emerged as a unique class of compounds that combine programmable nanoscale building blocks and atomic precision. As such, they bridge traditional semiconductors, molecular solids, and nanocrystal arrays by combining their most attractive features. Here, we(More)
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Temperature dependent thermal conductivities and thermal interface resistances of pentacene (Pn) thin films deposited on silicon substrates and self-assembled monolayer-modified [octadecyltrichlorosilane (OTS) and (3-aminopropyl)triethoxysilane (APTES)] silicon substrates were measured using frequency domain thermoreflectance. Atomic force microscopy images(More)
Thermal management plays a critical role in the design of solid state materials for energy conversion. Lead halide perovskites have emerged as promising candidates for photovoltaic, thermoelectric, and optoelectronic applications, but their thermal properties are still poorly understood. Here, we report on the thermal conductivity, elastic modulus, and(More)
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