Publications by authors named "Hao A Nguyen"

Here we report a series of nitrogen-rich conjugated macrocycles that mimic the structure and function of semiconducting 2D metal-organic and covalent organic frameworks while providing greater solution processability and surface tunability. Using a new tetraaminotriphenylene building block that is compatible with both coordination chemistry and dynamic covalent chemistry reactions, we have synthesized two distinct macrocyclic cores containing Ni-N and phenazine-based linkages, respectively. The fully conjugated macrocycle cores support strong interlayer stacking and accessible nanochannels.

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Single-photon sources are essential for advancing quantum technologies with scalable integration being a crucial requirement. To date, deterministic positioning of single-photon sources in large-scale photonic structures remains a challenge. In this context, colloidal quantum dots (QDs), particularly core/shell configurations, are attractive due to their solution processability.

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We demonstrate that active site ensembles on transition metal phosphides tune the selectivity of the nitrate reduction reaction. Using NiP nanocrystals as a case study, we report a mechanism involving competitive co-adsorption of H* and NO* intermediates. A near 100% faradaic efficiency for nitrate reduction over hydrogen evolution is observed at -0.

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Solution-processed semiconductors are in demand for present and next-generation optoelectronic technologies ranging from displays to quantum light sources because of their scalability and ease of integration into devices with diverse form factors. One of the central requirements for semiconductors used in these applications is a narrow photoluminescence (PL) line width. Narrow emission line widths are needed to ensure both color and single-photon purity, raising the question of what design rules are needed to obtain narrow emission from semiconductors made in solution.

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We demonstrate colloidal, layer-by-layer growth of metal oxide shells on InP quantum dots (QDs) at room temperature. We show with computational modeling that native InP QD surface oxides give rise to nonradiative pathways due to the presence of surface-localized dark states near the band edges. Replacing surface indium with zinc to form a ZnO shell results in reduced nonradiative decay and a density of states at the valence band edge that resembles defect-free, stoichiometric InP.

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Colloidal quantum dots (QDs) are promising candidates for single-photon sources with applications in photonic quantum information technologies. Developing practical photonic quantum devices with colloidal materials, however, requires scalable deterministic placement of stable single QD emitters. In this work, we describe a method to exploit QD size to facilitate deterministic positioning of single QDs into large arrays while maintaining their photostability and single-photon emission properties.

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This tutorial review presents our perspective on designing organic molecules for the functionalization of inorganic nanomaterial surfaces, through the model of an "anchor-functionality" paradigm. This "anchor-functionality" paradigm is a streamlined design strategy developed from a comprehensive range of materials (, lead halide perovskites, II-VI semiconductors, III-V semiconductors, metal oxides, diamonds, carbon dots, silicon, ) and applications (, light-emitting diodes, photovoltaics, lasers, photonic cavities, photocatalysis, fluorescence imaging, photo dynamic therapy, drug delivery, ). The structure of this organic interface modifier comprises two key components: anchor groups binding to inorganic surfaces and functional groups that optimize their performance in specific applications.

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