About

Yao Yang is an Assistant Professor in the Department of Chemistry and Chemical Biology at Cornell University. His research focuses on developing multimodal operando electron microscopy and synchrotron-based X-ray methods to address grand challenges in probing chemical dynamics of energy materials at solid-liquid interfaces across multiple spatiotemporal scales. His group is pushing the frontier of operando electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM), equipped with four-dimensional (4D) STEM, to interrogate the dynamic structural evolution of electrocatalysts at the atomic scale. Yang's work emphasizes understanding electrochemical mechanisms at interfaces, with particular attention to CO2 reduction, clean H2 production, and rechargeable batteries. His research involves designing and synthesizing shape-controlled nanocrystals and studying their activation and evolution under electrochemical conditions, aiming to enable the rational design of high-performance electrocatalysts. He also investigates fundamental electrochemistry at single-crystal electrode/electrolyte interfaces using advanced fabrication techniques, and visualizes the electrochemical double layer at solid-liquid interfaces at atomic scale to advance the understanding of interfacial electrocatalysis and electron transfer processes. His contributions include developing operando methods based on electron microscopy and synchrotron X-ray techniques to explore the structure and dynamics of energy materials, with the goal of improving energy efficiency and enabling renewable energy technologies.

Research topics

• Chemistry
• Organic chemistry
• Chemical engineering
• Nanotechnology
• Materials science
• Inorganic chemistry
• Physical chemistry

Selected publications

• Adapted Cell Design for the Operando X-Ray Absorption Study of a Structurally Evolving Cu Nanoparticle Ensemble during the CO ₂ Electroconversion to Multicarbon Products

  The Journal of Physical Chemistry C · 2025-12-23

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  An improved understanding of the materials that will sustain the future of energy production, storage, and delivery calls for better characterization tools. Operando characterization methods have thus become essential for investigating electrocatalytic materials. Without their resulting insights, the study of highly performing catalysts post-mortem cannot viably facilitate the further development of functional catalysts. Herein, we present an operando electrochemical cell designed for hard X-ray absorption spectroscopy (XAS) and specifically adapted to the study of an electrocatalytically active Cu nanoparticle ensemble. So far, this nanocatalyst has proven to pose quite a challenge to characterize due to its unique structural dynamics. Adopting a design comparable to the H-cell employed for all activity testing, we report the satisfactory translation of the active site formation into an XAS-compatible cell. The simultaneous collection of CO2-derived products during XAS characterization enabled the operando characterization of this CO2-reducing active structure. We report a Cu–Cu coordination number of the first scattering path higher than suggested in our previous studies, highlighting the importance of monitoring metastable nanoelectrocatalysts in operando. This study illustrates important caveats for the electrocatalysis community when considering the application of operando XAS. Our results highlight that the sample size, homogeneity, and stability determine how to interpret the measured signal. Considering these parameters carefully, the operando EXAFS results confirm the exceptional undercoordinated character of the Cu nanoparticle ensemble during CO2 reduction to C2+ products.

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• Electron Ptychography Resolves Individual Atomic Layers in Twisted Super-Moiré

  Microscopy and Microanalysis · 2025-07-01

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• Cyano group-modified graphitic carbon nitride for efficient charge transfer and enhanced photocatalytic H2O2 production

  Inorganic Chemistry Communications · 2025-06-09

  article1st author
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• Operando probing dynamic migration of copper carbonyl during electrocatalytic CO2 reduction

  Nature Catalysis · 2025-06-25 · 61 citations

  articleOpen access1st authorCorresponding
  PublisherOA PDFDOI

• Transport, Dynamics, and Phase Behavior of Soft Matter Under Nanoconfinement

  CHIMIA International Journal for Chemistry · 2025-11-26

  articleOpen access1st authorCorresponding

  Nanoscale confinement strongly alters the behavior of soft matter, from polymer crystallization to lipid self-assembly. In this mini review, we summarize recent progress on how confinement impacts molecular transport, crystallization, dynamics, and phase behavior in two distinct media: hard confinement in inorganic nanopores and soft confinement in lipidic mesophases. In the first part, we highlight polymer transport and dynamics in rigid nanopores, emphasizing how chain topology (linear, star-shaped, hyperbranched) governs confined crystallization and relaxation dynamics. In the second part, we turn to lipidic mesophases as biomimetic soft confining media, where phase transitions and molecular transport are intricately coupled to hydration and interfacial interactions. Together, these studies reveal that confinement effects arise not only from geometry but also from surface interactions, and that their interplay determines the structure and dynamics of confined matter. Understanding these principles opens avenues for applications in drug delivery, cryo-enzymology, and nanofabrication of functional materials and devices.

  PublisherOA PDFDOI

• Dynamic Evolution from Single-Atom Catalysts to Active Nanograins for CO₂ Reduction

  Journal of the American Chemical Society · 2025-10-03 · 10 citations

  articleSenior authorCorresponding

  Understanding dynamic catalyst evolution, particularly Cu-based single-atom catalysts, faces tremendous challenges of tracking rapid and nanoscale evolution and uncontrolled catalyst reoxidation during post-reaction air exposure. Although ex situ/in situ studies have indirectly indicated the structural reconstruction of single-atom catalysts, direct probing of single-atom catalyst evolution requires time-resolved nanoscale operando methods. Here, we present direct experimental evidence of dynamic evolution from single-atom catalysts to Cu nanostructures rich in active nanograins, based on a conductive metal–organic framework-based Cu single-atom catalyst (Cu-SAC). Operando synchrotron-based high-energy-resolution X-ray spectroscopy and IR absorption spectroscopy quantitatively tracked the structural and molecular fingerprints during single-atom-to-nanograin evolution. Cu-SAC supported on nanocarbon (Cu-SAC-NC) with nearly 100% metallic Cu nanograins achieved a 5-fold increase in multicarbon Faradaic efficiency (C2+ FE), relative to the Cu-SAC control group with less than half metallic Cu nanograins. Cu-SAC-NC, with superior electronic conductivity provided by the nanocarbon, facilitated the formation of dense copper carbonyl (Cu–CO) intermediates, leading to a larger fraction of active metallic Cu nanograins for effective C–C coupling and significantly enhanced C2+ selectivity. Operando electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM) directly captured real-time movies of dynamic structure evolution from isolated Cu single atoms to metallic Cu nanograins under the CO2RR. Operando electrochemical four-dimensional (4D) STEM reveals the complex polycrystalline Cu nanostructures rich in metallic nanograin boundaries, serving as catalytically active sites. This study paves the way for the design of a new generation of single-atom catalysts based on their operando active structures instead of pristine structures.

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• <i>Operando</i> Heating and Cooling Electrochemical Liquid-Cell STEM

  Microscopy and Microanalysis · 2025-07-01

  articleSenior author
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• <i>Operando</i> Heating and Cooling Electrochemical 4D-STEM Probing Nanoscale Dynamics at Solid–Liquid Interfaces

  Journal of the American Chemical Society · 2025-05-23 · 10 citations

  articleSenior authorCorresponding

  Operando/in situ methods have revolutionized our fundamental understanding of molecular and structural changes at solid–liquid interfaces and enabled the vision of “watching chemistry in action”. Operando transmission electron microscopy (TEM) emerges as a powerful tool to interrogate time-resolved nanoscale dynamics, which involve local electrical fields and charge transfer kinetics distinctly different from those of their bulk counterparts. Despite early reports on electrochemical or heating liquid-cell TEM, developing operando TEM with simultaneous electrochemical and thermal control remains a formidable challenge. Here, we developed operando heating and cooling electrochemical liquid-cell scanning TEM (EC-STEM). By integrating a three-electrode electrochemical circuit and an additional two-electrode thermal circuit, we can investigate heterogeneous electrochemical kinetics across a wide temperature range of −50 to 300 °C. We used Cu electrodeposition/stripping processes as a model system to demonstrate quantitative electrochemistry from −40 to 95 °C in both transient and steady states in aqueous and organic solutions, which paves the way for investigating energy materials operating in extreme climates. Machine learning-assisted quantitative 4D-STEM structural analysis in cold liquids (−40 °C) reveals a distinct two-stage growth of nanometer-scale mossy Cu nanoislands with random orientations followed by μm-scale Cu dendrites with preferential orientations. This work benchmarked electrochemistry in the three-electrode EC-STEM and systematically investigated the temperature and pH dependence of the Pt pseudoreference electrode (RE). At room temperature, the Pt pseudo-RE shows a reliable potential of 0.8 ± 0.1 V vs the standard hydrogen electrode and remains pH-independent on the reversible hydrogen electrode scale. We anticipate that operando heating/cooling EC-STEM will become invaluable for understanding fundamental temperature-controlled nanoscale electrochemistry and advancing renewable energy technologies (e.g., catalysts and batteries) in realistic climates.

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• Isotope Effects for Water at Pt(111) Computed with Nuclear−Electronic Orbital Theory

  The Journal of Physical Chemistry Letters · 2025-12-12 · 2 citations

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  Hydrogen/deuterium (H/D) substitution at electrochemical interfaces can provide insights into fundamental electrochemical processes. Periodic nuclear–electronic orbital density functional theory (NEO-DFT), which treats specified nuclei quantum mechanically on the same level as the electrons, enables such H/D isotope effects to be investigated computationally. Herein, periodic NEO-DFT is applied to OH–/OD– adsorption, H/D adsorption, and H2O/D2O monolayers at a Pt(111) surface. These calculations inherently include anharmonic zero-point energy and nuclear delocalization of hydrogen and deuterium. Thus, they capture structural differences between H/D isotopologues, guide interpretation of experimental cyclic voltammograms, identify favored adsorption sites, and characterize differences in H2O/D2O hydrogen-bonding interactions. Periodic NEO-DFT maintains the favorable computational scaling of conventional DFT, predicts geometric isotope effects, and can be combined with techniques to model an applied potential. Thus, periodic NEO-DFT represents a promising tool for probing the structures of electrochemical interfaces, interpreting experimental isotope studies, and elucidating electrocatalytic mechanisms.

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• 3D‐Printed Bioinspired Meta‐Structural Perovskite Catalysts for Dry Reforming of CH ₄ and CO ₂

  Advanced Materials · 2025-07-30 · 6 citations

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  Abstract Conventional packed‐bed catalysts suffer from single‐scale porosity, insufficient mechanical strength, and suboptimal mass transfer efficiency. Inspired by the fractal structure of the lung bronchi, a design and 3D printing method for gradient meta‐structural catalysts is proposed by integrating synthesized LaFe 0.5 Ni 0.5 O 3 (LFN) perovskite with pseudo‐boehmite, achieving ultralow pressure drop and high catalytic efficiency. Computational fluid dynamics and reaction simulations guide the design of uniform and gradient‐structured catalysts with hierarchical woodpile channels (0.5–3 mm). Compared with homogeneous catalysts, the gradient design theoretically exhibits 1.5‐fold and 1.1‐fold increases in flow velocity and hydrogen production, respectively. Meta‐structural catalysts are fabricated with gradient multi‐peak pore distribution (9.32 nm, 103.75 nm) by regionally modulating unit cell sizes and LFN content (11–35%) combined with the dehydroxylation of pseudo‐boehmite. 3D‐printed perovskite catalysts demonstrate a 78.7‐fold increase in specific surface area (102.26 m 2 g −1 ) and compressive strength of 8.48 MPa. In dry reforming of methane (DRM) tests, it achieves 82.13% CH 4 conversion, and 9.69 mmol g −1 syngas yield, outperforming conventional powder‐packed beds by 10% efficiency. This study achieves mass transfer and catalytic performance coupling by tuning gradient hierarchical pores and tailoring flow dynamics, offering a paradigm for robust, high‐efficiency catalyst design across diverse applications.

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Frequent coauthors

• Peidong Yang

  University of California, Berkeley

  79 shared

• Héctor D. Abruña

  Cornell University

  78 shared

• David A. Muller

  Cornell University

  45 shared

• Julian Feijóo

  Ludwig-Maximilians-Universität München

  31 shared

• Chubai Chen

  University of California, Berkeley

  27 shared

• Francis J. DiSalvo

  Cornell University

  23 shared

• Jianbo Jin

  University of California, Berkeley

  20 shared

• Yu‐Tsun Shao

  University of Southern California

  20 shared

Labs

• Yao Yang GroupPI

Education

• Mr., Department of Chemistry and Chemical Biology

  Cornell University

Awards & honors

• 2025 ACS Materials and Interfaces Outstanding Presentations…
• 2024 Journal of Materials Research (JMR) Distinguished Invit…
• 2021-2024 Miller Postdoctoral Fellowship at UC Berkeley
• 2023 Best Early Career Presentation at MRS Spring (Symposium…
• 2022 ACS AC/DC Rising Stars in Analytical Chemistry