All Publications

  • Dynamic fracture processes in hydrogen embrittled iron ACTA MATERIALIA Lee, A. C., Parakh, A., Lam, S., Sleugh, A., Tertuliano, O., Doan, D., Weker, J., Hosemann, P., Gu, X. 2023; 259
  • Synthesis of multifunctional amorphous metallic shell on crystalline metallic nanoparticles. RSC advances Parakh, A., Kiani, M. T., Lindgren, E., Colmenares, A., Lee, A. C., Suzuki, Y., Gu, X. W. 2023; 13 (43): 30491-30498


    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

  • Detection of voids in hydrogen embrittled iron using transmission X-ray microscopy INTERNATIONAL JOURNAL OF HYDROGEN ENERGY Lee, A. C., Parakh, A., Sleugh, A., Tertuliano, O. A., Lam, S., Weker, J., Hosemann, P., Gu, X. 2023; 48 (5): 1968-1978
  • Direct Observation of the Pressure-Induced Structural Variation in Gold Nanoclusters and the Correlated Optical Response. Nano letters Li, Q., Zeman, C. J., Kalkan, B., Kirschbaum, K., Gianopoulos, C. G., Parakh, A., Doan, D., Lee, A. C., Kulikowski, J., Schatz, G. C., Shen, G., Kunz, M., Gu, X. W. 2022


    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

  • High-pressure deformation of metallic glass nanoparticles JOURNAL OF NON-CRYSTALLINE SOLIDS Parakh, A., Kiani, M. T., Colmenares, A., Lee, A. C., Shen, G., Chariton, S., Prakapenka, V. B., Gu, X. 2022; 597
  • High pressure deformation induced precipitation in Al-Zn-Mg-Cu alloy (Al7075) MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING Parakh, A., Lee, A. C., Chariton, S., Wang, M. M., Kiani, M. T., Prakapenka, V. B., Gu, X. 2022; 853
  • Ultrafine-grained Ni-rich layered cathode for advanced Li-ion batteries ENERGY & ENVIRONMENTAL SCIENCE Park, G., Yoon, D., Kim, U., Namkoong, B., Lee, J., Wang, M. M., Lee, A. C., Gu, X., Chueh, W. C., Yoon, C. S., Sun, Y. 2021

    View details for DOI 10.1039/d1ee02898g

    View details for Web of Science ID 000721948000001

  • Thermal enhancement and shape stabilization of a phase-change energy-storage material via copper nanowire aerogel CHEMICAL ENGINEERING JOURNAL Zhang, L., An, L., Wang, Y., Lee, A., Schuman, Y., Ural, A., Fleischer, A. S., Feng, G. 2019; 373: 857–69