Andrew Lee
Ph.D. Student in Materials Science and Engineering, admitted Autumn 2019
Masters Student in Materials Science and Engineering, admitted Autumn 2021
Other Tech - Graduate, Stanford Nano Shared Facilities
All Publications
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Dynamic fracture processes in hydrogen embrittled iron
ACTA MATERIALIA
2023; 259
View details for DOI 10.1016/j.actamat.2023.119234
View details for Web of Science ID 001070580700001
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Synthesis of multifunctional amorphous metallic shell on crystalline metallic nanoparticles.
RSC advances
2023; 13 (43): 30491-30498
Abstract
Colloidal nanoparticles can be coated with a conformal shell to form multifunctional nanoparticles. For instance, plasmonic, magnetic, and catalytic properties, chemical stability and biocompatibility can be mixed and matched. Here, a facile synthesis for depositing metal boride amorphous coatings on colloidal metallic nanocrystals is introduced. The synthesis is independent of core size, shape, and composition. We have found that the shell synthesis is limited to nanoparticles capped with short molecular weight and low binding energy ligands, and does not work with polyvinylpyrrolidone (PVP)-coated Ag nanoparticles or thiol-coated Au nanoparticles. Shell thickness can be as thin as 3 nm with no apparent pinholes. High pressure studies show that the coatings are highly resistant to crystallization and are strongly bonded to the crystalline core. By choosing either CoB or NiB for the coating, the composite nanoparticles can be either ferromagnetic or paramagnetic at room temperature, respectively.
View details for DOI 10.1039/d3ra06093d
View details for PubMedID 37860175
View details for PubMedCentralID PMC10582685
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Direct Observation of the Pressure-Induced Structural Variation in Gold Nanoclusters and the Correlated Optical Response.
Nano letters
2022
Abstract
The ability to gradually modify the atomic structures of nanomaterials and directly identify such structural variation is important in nanoscience research. Here, we present the first example of a high-pressure single-crystal X-ray diffraction analysis of atomically precise metal nanoclusters. The pressure-dependent, subangstrom structural evolution of an ultrasmall gold nanoparticle, Au25S18, has been directly identified. We found that a 0.1 Å decrease of the Au-Au bond length could induce a blue-shift of 30 nm in the photoluminescence spectra of gold nanoclusters. From theoretical calculations, the origins of the blue-shift and enhanced photoluminescence under pressure are investigated, which are ascribed to molecular orbital symmetry and conformational locking, respectively. The combination of the high-pressure in situ X-ray results with both theoretical and experimental optical spectra provides a direct and generalizable avenue to unveil the underlying structure-property relations for nanoclusters and nanoparticles which cannot be obtained through traditional physical chemistry measurements.
View details for DOI 10.1021/acs.nanolett.2c03759
View details for PubMedID 36577713
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Detection of voids in hydrogen embrittled iron using transmission X-ray microscopy
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
2023; 48 (5): 1968-1978
View details for DOI 10.1016/j.ijhydene.2022.10.059
View details for Web of Science ID 000917479700001
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High-pressure deformation of metallic glass nanoparticles
JOURNAL OF NON-CRYSTALLINE SOLIDS
2022; 597
View details for DOI 10.1016/j.jnoncrysol.2022.121923
View details for Web of Science ID 000876499400005
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High pressure deformation induced precipitation in Al-Zn-Mg-Cu alloy (Al7075)
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
2022; 853
View details for DOI 10.1016/j.msea.2022.143765
View details for Web of Science ID 000849830800002
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Ultrafine-grained Ni-rich layered cathode for advanced Li-ion batteries
ENERGY & ENVIRONMENTAL SCIENCE
2021
View details for DOI 10.1039/d1ee02898g
View details for Web of Science ID 000721948000001
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Thermal enhancement and shape stabilization of a phase-change energy-storage material via copper nanowire aerogel
CHEMICAL ENGINEERING JOURNAL
2019; 373: 857–69
View details for DOI 10.1016/j.cej.2019.05.104
View details for Web of Science ID 000471682900082