Yao Yang

Overview

Our group 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. We are pushing and defining the frontier of operando electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM), equipped with four-dimensional (4D) STEM, to interrogate dynamic structural evolution of electrocatalysts at the atomic scale. Our group and labs will open in July 2024 for recruiting graduate students and postdoctoral researchers.

For inquiries, you can reach out via yaoyang@cornell.edu

Research Focus

Electrochemistry lies at the interface of chemistry and energy materials and represents one of the most promising approaches for enhancing energy efficiency, mitigating environmental impacts and carbon emissions, and enabling renewable energy technologies. Our research focuses on the fundamental understanding of electrochemical mechanisms at interfaces with an emphasis on CO₂ reduction, clean H₂ production and rechargeable batteries. The central scheme of the Yang group lies in developing operando methods, based on advanced electron microscopy facilities at Cornell Center for Materials Research (CCMR) and synchrotron X-ray methods at Cornell High Energy Synchrotron Source (CHESS), to investigate fundamental aspects of solid-liquid interfaces related to renewable energy technologies:

1. Operando electrochemistry at well-defined nanocrystal electrocatalyst/electrolyte interfaces:

Shape-controlled nanocrystals (1-100 nm) exclusively/selectively expose certain facets that can enable tunable catalyst activity/selectivity. They can bridge the knowledge gap between bulk single-crystal electrodes in the electrochemistry community and practical nanoparticles in the materials science community. While there are numerous studies on the synthesis of shape-controlled nanocrystals and characterization of their pristine structures, few studies have attempted to investigate how they activate and/or evolve/deactivate under electrochemical conditions. The project focuses on the design and colloidal synthesis of size- and shape-controlled 0D and 1D metal and oxide nanocrystals and their assembly into 2D and 3D periodic architectures as model systems for operando mechanistic studies. Fundamental insights gained from these studies will enable the rational design of high-performance CO₂ reduction electrocatalysts with tunable selectivity and activity.

2. Fundamental electrochemistry at single-crystal electrode/electrolyte interfaces

Single-crystal metals and oxides provide an ideal materials platform with atomic-level control of surface structure/composition to reveal the structure-(re)activity relationships/correlations of electrocatalysts. This project takes advantage of the design and fabrication of well-defined single-crystal metal electrodes by the Clavilier method (Cornell is one of the few places in the world with such a capability.) and single-crystal oxide superlattices by molecular beam epitaxy (MBE) at the NSF supported PARADIM (Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials) Facility. Single-crystal metals and oxides will serve as well-defined electrode surfaces, which can provide an accurate description of the structure of surface adsorbates for theoretical simulations and guide the design of efficient high performing electrocatalysts for H₂ production.

3. Visualizing the electrochemical double layer at solid-liquid interfaces at atomic scale

The electrochemical double layer (EDL) is one of the “Grand Challenges/Holy Grails” of physical chemistry that has attracted generations of electrochemists. Resolving/visualizing the EDL is key to advancing our fundamental understanding of interfacial electrocatalysis, electron transfer as well as ionic and potential gradients at charged interfaces. The project focuses on developing operando electron microscopy and synchrotron X-ray methods to provide experimental mapping of the EDL. An important example is the formation of the solid-electrolyte interphase (SEI), which determines the cycle life, charge rate and safety of lithium metal or ion based batteries.

Awards and Honors

• 2021-2024 Miller Postdoctoral Fellowship at UC Berkeley
• 2023 Best Early Career Presentation at MRS Spring 2023 (Symposium CH01)
• 2022 ACS AC/DC Rising Stars in Analytical Chemistry                             
• 2020 Wentink Award   
• 2020 Cornell High-Energy Synchrotron Source (CHESS) Student Research Award
• 2019 Microscopy Society of America (MSA) Student Poster Award             
• 2018 Howard Neal Wachter Memorial Prize 

 

In the News:

1. Kavli Foundation Nanoscience Profile of Dr. Yao Yang. Catalyst Chemistry Could Turn Emissions into Green Fuels.
2. How a Record-Breaking Copper Catalyst Converts CO₂ Into Liquid Fuels
3. Carbon-coated nickel enables fuel cell free of precious metals

Publications

1. Operando Studies Reveal Active Cu Nanograins for CO₂ Electroreduction. Nature 2023, 614, 262.
2. Inverse Kinetic Isotope Effects on the Oxygen Reduction Reaction at Pt Single Crystals. Nat. Chem. 2023, 15, 271. 
3. Octahedral Spinel Electrocatalysts for Alkaline Fuel Cells. Proc. Natl. Acad. Sci. 2019, 116, 244425.
4. A Completely Precious-Metal-Free Alkaline Fuel Cell with Enhanced Performance Using a Carbon-Coated Nickel Anode. Proc. Natl. Acad. Sci. 2022, 119, e2119883119
5. Revealing the Atomic Ordering of Binary Intermetallics Using In Situ Heating Techniques at Multilength Scales. Proc. Natl. Acad. Sci. 2019, 116, 1974.
6. In Situ X-ray Absorption Spectroscopy of a Synergistic Co−Mn Oxide Catalyst for the Oxygen Reduction Reaction. J. Am. Chem. Soc. 2019, 141, 1463.
7. Elucidating Cathodic Corrosion Mechanisms with Operando Electrochemical Transmission Electron Microscopy. J. Am. Chem. Soc. 2022, 144, 15698.
8. Operando Resonant Soft X‑ray Scattering Studies of Chemical Environment and Interparticle Dynamics of Cu Nanocatalysts for CO₂ Electroreduction. J. Am. Chem. Soc. 2022, 144, 8927.
9. Operando High-Energy-Resolution X-ray Spectroscopy of Evolving Cu Nanoparticle Electrocatalysts for CO₂ Reduction. J. Am. Chem. Soc. 2023, 145, 20208.
10. Chemical and Structural Evolution of AgCu Catalysts in Electrochemical CO₂ Reduction. J. Am. Chem. Soc. 2023, 145, 10116.
11. Cobalt-Based Nitride-Core Oxide-Shell Oxygen Reduction Electrocatalysts. J. Am. Chem. Soc. 2019, 141, 19241.
12. Combinatorial Studies of Palladium-Based Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells, J. Am. Chem. Soc. 2020, 142, 8, 3980.
13. Metal−Organic-Framework-Derived Co−Fe Bimetallic Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells. J. Am. Chem. Soc. 2019, 141, 10744.
14. A Strategy for Increasing the Efficiency of the Oxygen Reduction Reaction in Mn-Doped Cobalt Ferrites. J. Am. Chem. Soc. 2019, 141, 4412.
15. Pt-Decorated Composition-Tunable Pd-Fe@Pd/C Core-Shell Nanoparticles with Enhanced Electrocatalytic Activity towards the Oxygen Reduction Reaction. J. Am. Chem. Soc. 2018, 140, 7248.
16. Nonprecious Transition Metal Nitrides as Efficient Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells. Sci. Adv. 2022, 8, eabj1584.
17. Electrocatalysis in Alkaline Media and Alkaline-Based Energy Technologies. Chem. Rev. 2021, 122, 6117-6321.
18. Yang,* Operando Methods: A New Era of Electrochemistry. Curr. Opin. Electrochem. 2023, 42, 101403.