Utkur Mirziyodovich MIRSAIDOV
PhD, University of Texas, Austin, USA (2005)
Associate Professor

Email: mirsaidov@nus.edu.sg
Office: S1A-02-11
Tel: +65 6516 6192

Current Research

  • The broad goal of our research program is to understand the underlying mechanisms of chemical and physical processes involved in fabrication and application of nanomaterials. We study nanomaterials in a wide range of industrially relevant processes, such as developing processes that enable device scaling in semiconductor manufacturing, catalysis, electrochemistry, and energy storage. To gain mechanistic insight into the fundamental processes of materials fabrication and applications, we mostly use in situ liquid-phase, gas-phase, and cryogenic transmission electron microscopy (TEM) imaging approach along with other complementary techniques. Our approach enables us to visualize many nanoscale processes in real-time under relevant liquid and gaseous environments directly, hence we can identify elusive transient stages in many materials-related processes.

    • Currently, we are working on three broad topics:

    • Addressing challenges in the semiconductor industry: Processes development for overcoming scaling issues. The key challenge that confronts the microelectronics industry is conforming to Moore’s law by increasing the density of transistors on a chip using high-aspect-ratio 3D nano-architectures. While increasing device density by packing devices into 3D nano-architectures can address the scaling issue, 3D architectures pose new fundamental challenges in terms of fabrication. In current fabrication processes, liquid or gaseous chemicals etch, grow, clean, and coat the wafer surfaces on which nanometer-size features are progressively fabricated. Today, using lithographic processes, we write nanoscale patterns over large 2D areas. However, the ability to write the nanoscale patterns does not directly translate into the chemical ability to fabricate 3D structures at the same length scales because of the failure modes in etching, growing, and cleaning of vertical nanostructures. To understand and improve the nanoscale processes associated with the fabrication of vertical channel materials (in transistors) and ‘scaling boosters’ in metal interconnects (device packaging), we first have to visualize them and pinpoint the possible intermediate stages that lead to their failure during the fabrication. Our goal is to identify mechanisms in semiconductor fabrication-related processes by taking a very direct approach to image nanostructures (used in device fabrication) in real-time as they are undergoing relevant chemical or physical processes encountered in semiconductor industry.
    • Insight into catalytic processes by identifying the link between function and structure. During catalysis, the dynamical structure of a nanoparticle catalyst, which only exists within the reactive environment, determines the availability of active sites on its surface, which in turn determines its catalytic properties. However, how nanoscale catalysts change their structure under reaction conditions and become catalytically active is poorly understood and hotly debated. The lack of understanding here is mainly due to the challenge of observing the nanocatalysts during the reaction within a gas or liquid phase at elevated temperatures. Our goal is to establish the function–structure relation (activity vs. catalyst’s surface structure) by studying the surface of catalysts and the interface between the catalysts and a support material.
    • Mechanistic understanding of nanomaterials synthesis: Nanomaterials with different architecture (shape, structure, and materials composition) are commonly synthesized from precursor solutions through one-pot reactions, seed-mediated synthesis, or through the reshaping of template nanoparticles. Currently, nanomaterials synthesis still remains as an art based on well-tuned recipes that are derived from laborious trial-and-error approaches. Our goal is to determine the fundamental underlying chemical and physical processes that govern the formation of nanomaterials from the solution phase and provide a rational route to synthesis using direct real-time TEM imaging.

    Selected Publications

    • U. Anand, T. Ghosh, Z. Aabdin, S. Koneti, X. M. Xu, F. Holsteins, U. Mirsaidov, “Nanoscale Wetting of Patterned Surfaces.” Proceedings of National Academy of Sciences U.S.A. 118(38), e2108074118 (2021).
    • X. Liu, S.-W. Chee, S. Raj, M Sawczyk, P. Kral, U. Mirsaidov, “Three-Step Nucleation of Metal-Organic Framework Nanocrystals.” Proceedings of National Academy of Sciences U.S.A. 118(10), e2008880118 (2021).
    • S. W. Chee, J. Arce-Ramos, W. Li, A. Genest, U. Mirsaidov, “Structural Changes in Noble Metal Nanoparticles during CO Oxidation and Their Impact on Catalyst Activity” Nature Communications 11, 2133 (2020).
    • S. W. Chee, Z. Wong, Z. Baraissov, S. F. Tan, T.-L. Tan, U. Mirsaidov, “Interface Mediated Kirkendall Effect and Nanoscale Void Migration in Bimetallic Nanoparticles During Interdiffusion.” Nature Communications 10, 2831 (2019).
    • S. W. Chee, S. F. Tan, Z. Baraissov, M. Bosman, U. Mirsaidov, “Direct Observation of the Nanoscale Kirkendall Effect During Galvanic Replacement Reactions.” Nature Communications 8, 1224 (2017).
    • N. D. Loh, S. Sen, M. Bosman, S. F. Tan, J. Zhong, C. Nijhuis, P. Kral, P. Matsudaira, and U. Mirsaidov, “Multi-step Nucleation of Nanocrystals.” Nature Chemistry 9, 77–82 (2017).

    Affiliations & Links

    • Department of Biological Sciences
    • Centre for BioImaging Sciences
    • Dean’s Chair
    • Mirsaidov Lab