About

Zhenan Bao is the K.K. Lee Professor in Chemical Engineering at Stanford University, with courtesy appointments in Chemistry, Bioengineering, and Materials Science and Engineering. She joined Stanford in 2004 and has served as the Department Chair of Chemical Engineering from 2018-2022 and in 2025. Bao is the founder and current faculty director of the Stanford Wearable Electronics Initiative (eWEAR). Her research focuses on molecular design concepts and fabrication processes to advance skin-inspired electronics, including the development of new materials and device solutions for soft robotics, wearable and implantable electronics for health monitoring, and neuroscience applications. Her group has made significant contributions to understanding the nano confinement effect of conjugated polymers, establishing foundational materials for skin-inspired electronic devices that enable unprecedented opportunities for health monitoring, diagnosis, and treatment. Bao has pioneered the creation of devices such as neuromorphic e-skin, wireless wound healing patches, and reconfigurable self-healing electronic skin, which are used for applications in neurochemical monitoring, neurotechnology, and human health. She holds over 800 refereed publications and more than 80 US patents, and her work has been recognized with numerous awards and honors, including election to the US National Academy of Sciences, National Academy of Engineering, and the American Academy of Arts and Sciences.

Research topics

• Computer Science
• Materials science
• Nanotechnology
• Chemistry
• Artificial Intelligence
• Engineering
• Electrical engineering
• Biology
• Composite material
• Organic chemistry
• Chemical engineering
• Inorganic chemistry
• Thermodynamics
• Optoelectronics
• Physical chemistry
• Neuroscience
• Physics
• Cell biology
• Biochemistry
• Medicine
• Endocrinology
• Electronic engineering
• Optics
• Data science

Selected publications

• Low-Channel EMG Gesture Recognition via Sparse-To-Dense Representation Learning

  2026-04-21

  articleSenior author

  Electromyography (EMG) has recently emerged as a promising modality for wearable gesture interfaces. However, wearable EMG devices face an inherent trade-off between user comfort and the need for large-area sensing for high-resolution data collection. We propose a self-supervised representation learning framework, trained on a 32-channel dataset and enabling lower channel device to leverage the pre-trained muscle activity correlations. In addition, we incorporate a meta-learning strategy with channel permutation, which improves robustness to electrode placement shifts and allows rapid adaptation with only a few fine-tuning cycles. Connected with downstream classifiers, the model achieved comparable performance on American Sign Language Translation with reduced sensor count.

  PublisherDOI

• Intrinsically stretchable complementary circuits based on direct photo-patternable polymer semiconductors

  Nature Electronics · 2026-04-15

  articleSenior authorCorresponding
  PublisherDOI

• Solution-state nanoconfined aggregation and microstructure evolution in blends of conjugated polymers and elastomers

  Proceedings of the National Academy of Sciences · 2026-04-24

  articleOpen accessSenior authorCorresponding

  Emerging wearable health monitoring technologies require conformable and stretchable devices. Polymer semiconductors composed of π-conjugated polymer aggregates in an elastomeric matrix are remarkable in their ability to provide both high stretchability and enhanced charge transport. Understanding their film formation process is critical in improving charge transport, imparting added functionalities, and advancing large-scale production of high-performing polymer electronic devices. Here, using a poly-thieno[3,2-b]thiophene-diketopyrrolopyrrole (DPPTT): polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) blend as a model system, electron tomography of the blend reveals the presence of bundles of conjugated polymer nanofibers spanning the thickness of the films. High-resolution cryogenic electron microscopy (cryo-EM) of solution and thin films reveals that the nanoconfined DPPTT nanofibers in blends are composed of the aligned DPPTT 1D aggregates present in solution. In contrast, neat DPPTT solutions and thin films contain irregular crystalline domains with random orientations. In situ grazing incidence wide-angle X-ray scattering (GIWAXS) studies reveal that DPPTT crystallization commences earlier in blends compared to neat films. Combining observations from both in situ ultraviolet-visible spectroscopy, in situ GIWAXS and cryo-EM reveal that 1D aggregates in blend solution bundle and align into interconnected larger fibers that are nanoconfined in the SEBS matrix. This morphology is desirable for efficient charge transport and good mechanical strength. In contrast, neat DPPTT films contain randomly oriented smaller aggregates with an increased fraction of disordered domains. Overall, our work provides critical insights on the impact of solution composition and processing conditions on thin film morphology for achieving multifunctional high-performing electronic polymer composites.

  PublisherDOI

• Synchronized Breathing in Anion-Derived Interphases

  ACS Energy Letters · 2025-07-12 · 6 citations

  article

  Anion-derived interphases are crucial for extending the cycle life of lithium metal batteries. While their benefits are often attributed to crystalline inorganic species like LiF and Li2O, the role of amorphous inorganic species and the interplay between the anode-electrolyte interphase (SEI) and the cathode-electrolyte interphase (CEI) remain largely unexplored. In this study, we examine two model electrolyte systems─one with solvent-derived interphases and the other with anion-derived interphases─using advanced X-ray scattering and spectroscopy techniques. Our findings reveal that anion-derived interphases contain substantial amounts of amorphous inorganic species, leading to a unique synchronization of “breathing” between SEI and CEI. During charging, the SEI grows while the CEI shrinks; during discharging, these roles reverse. This distinctive interfacial behavior originates from the competition of deposition and dissolution of amorphous inorganics during cycling. The study highlights the unique role of amorphous inorganics in anion-derived interphases, providing new insights into improving battery performance and durability.

  PublisherDOI

• Elucidating the Effects of LiF on Lithium Metal Anodes

  Nano Letters · 2025-09-29 · 20 citations

  articleCorresponding

  O. These findings shed light on the effects of LiF on Li metal anodes and the arrangement characteristic of LiF within the SEI. By integrating key discoveries regarding LiF, a projected working mechanism for LiF is illustrated. Overall, our study on LiF provides valuable insights that advance the understanding of the SEI and interphase nanostructures, contributing to the development of more reliable and practical Li metal batteries.

  PublisherDOI

• A simplified wearable device powered by a generative EMG network for hand-gesture recognition and gait prediction

  Nature Sensors · 2025-12-01 · 11 citations

  articleSenior author
  PublisherDOI

• <i>(Battery Division Postdoctoral Associate Research Award Sponsored by MTI Corporation and the Jiang Family Foundation)</i> Molecular LOGICS of Li Metal Battery: From Interface to Interphase

  ECS Meeting Abstracts · 2025-11-24

  articleSenior author

  Conventional electrochemistry centers on well-defined charge-transfer processes at idealized, “clean” solid–liquid interfaces. In contrast, next-generation energy systems—such as high-energy-density lithium-metal batteries (LMBs)—present a far more complex interfacial landscape, where the formation of a solid–electrolyte interphase (SEI) fundamentally reshapes electron–ion interactions. Although essential for enabling LMBs, the molecular formation mechanisms, evolving structure, and spatial heterogeneity of the SEI remain incompletely understood. In this talk, I will present our recent efforts to decode the molecular principles governing SEI functionality. By combining electrochemical analysis, non-washing X-ray photoelectron spectroscopy (XPS), and synchrotron-based X-ray absorption spectroscopy (XAS), we elucidate how decomposition pathways and microscale heterogeneities dictate SEI composition and performance. Our findings reveal that not all decomposition products remain in the SEI—many persist dissolved—highlighting the critical role of semi-soluble, anion-derived species (e.g., LiF) in forming robust, porous, electrolyte-trapping interphases. Furthermore, we reinterpret the classical electric double layer (EDL) within nanoconfined SEI environments, uncovering key interfacial properties that govern the reversibility of lithium plating and stripping. By retro-engineering the EDL at the molecular scale, we establish essential design principles to optimize the next-generation LMBs. These insights bridge molecular interfacial chemistry with macroscopic battery performance, providing a rational framework for electrolyte and interface engineering toward durable, high-efficiency energy storage systems.

  PublisherDOI

• Arginine-Specific Molecularly Imprinted Polymer-Based Laser-Induced Graphene Flexible Sensor

  ChemRxiv · 2025-11-04

  preprintOpen accessSenior author

  Non-invasive monitoring of biomarkers is crucial for the wide adoption of health monitoring and the early detection of health conditions. L-Arginine, a conditionally essential amino acid with a variety of significant physiological roles, is critical for the pathogenesis of various cardiovascular diseases (CVD) such as endothelial dysfunction, neurodegenerative disorders, and overall homeostasis. However, current methods of detection of L-Arginine are unsuitable for continuous monitoring due to their heavy requirements on resources and invasive sampling. Here, we describe the fabrication of an L-Arginine-specific electrochemical sensor by integrating a Molecularly Imprinted Polymer (MIP) on a PEDOT:PSS modified Laser-Induced Graphene (LIG) electrode on a flexible substrate. The MIPs function as sensitive and selective synthetic receptors for L-Arginine, while the PEDOT:PSS electrodeposited LIG electrode provides low impedance and a high sensitivity detection. The MIP-PEDOT:PSS-LIG platform uses Electrochemical Impedance Spectroscopy (EIS) and demonstrates exceptional analytical performance, achieving a low Limit of Detection (LOD) (~1 nm) and a wide linear dynamic range (1 nM to 1 mM), effectively covering the physiologically relevant concentrations of arginine in sweat. The sensor exhibited high selectivity against structurally similar amino acids (lysine, histidine, and citrulline) and maintained robust linearity (R² ~ 0.98) when tested in an artificial sweat medium. Furthermore, the device exhibited excellent reusability and stability via controlled electrostatic regeneration, demonstrating robustness and applicability within artificial sweat. In summary, a sensitive and selective MIP is developed which enables non-invasive sensing of L-arginine with readily made flexible electrodes and provides a promising device for next-generation point-of-care diagnostics and health monitoring.

  PublisherOA PDFDOI

• Intrinsically stretchable transistors and integrated circuits

  Nature Reviews Electrical Engineering · 2025-11-05 · 6 citations

  articleSenior author
  PublisherDOI

• Revealing Solvent-Assisted Li ⁺ Transport in the Solid Electrolyte Interphase <i>operando</i>

  Journal of the American Chemical Society · 2025-11-07 · 4 citations

  articleSenior authorCorresponding

  The performance of energy-dense lithium metal batteries is critically influenced by the properties of the solid electrolyte interphase (SEI). Yet, progress in understanding this layer has been limited by the lack of accurate operando characterization because the SEI evolves dynamically during cycling. Here, we apply dynamic electrochemical impedance spectroscopy (dEIS) to resolve the real-time evolution of the SEI on lithium metal in ether-based electrolytes with varying degrees of fluorination. We find that faster stabilization of the compact SEI resistance correlates with improved passivation and higher Coulombic efficiency. Unexpectedly, compact SEI resistance correlates directly with Li+ solvation energy, revealing that weaker Li+ solvation increases not only bulk but also interphase resistance. These findings challenge the conventional view of the SEI as a purely solid-phase conductor and instead support a solvent-assisted Li+ transport mechanism within the compact SEI. This framework emphasizes the need to balance SEI ionic conductivity with the Li+ solvation environment to maximize lithium metal battery performance.

  PublisherDOI

Recent grants

• Patterning of Large Array Organic Semiconductor Single Crystals

  NSF · $441k · 2013–2016

• Mechanistic Studies of Carbon Naotube Sorting on Functional Surfaces

  NSF · $350k · 2009–2012

• NIRT: Synthesis, Electrical and Optical Properties of Metal-Molecule-Metal Junctions formed by Self-Assembly

  NSF · $1.4M · 2005–2010

• DMREF: High-Throughput Morphology Prediction for Organic Solar Cells

  NSF · $900k · 2014–2017

• Liquid phase organic transistor sensor platform based on surface sorted semiconducting carbon nanotubes for small molecules and biological targets

  NSF · $360k · 2012–2015

Frequent coauthors

• Michael F. Toney

  146 shared

• Stefan C. B. Mannsfeld

  144 shared

• Yi Cui

  Stanford University

  132 shared

• Jeffrey B.‐H. Tok

  Stanford University

  126 shared

• Mark E. Roberts

  Clemson University

  99 shared

• Xiaodan Gu

  University of Southern Mississippi

  96 shared

• Thomas F. Jaramillo

  94 shared

• Joon Hak Oh

  Seoul National University

  88 shared

Labs

• Bao Research GroupPI

Education

• Ph.D., Materials Science and Engineering

  Stanford University

  1999

• M.S., Polymer Materials and Engineering

  University of Science and Technology of China

  1996

• B.S., Polymer Materials and Engineering

  University of Science and Technology of China

  1993

Awards & honors

• VinFuture Prize Female Innovator 2022
• ACS Award of Chemistry of Materials 2022
• MRS Mid-Career Award 2021
• AICHE Alpha Chi Sigma Award 2021
• ACS Central Science Disruptor and Innovator Prize 2020