Skin-inspired sensing and actuating technologies: from cephalopod camouflage to human tactile perception

Professional Education

  • Doctor of Philosophy, University of California Irvine (2020)
  • Doctor of Philosophy, University of California, Irvine, Materials Science and Engineering (2020)

Stanford Advisors

All Publications

  • Tunable 1D and 2D Polyacrylonitrile Nanosheet Superstructures. ACS nano Gong, H., Patino, D. U., Ilavsky, J., Kuzmenko, I., Peña-Alcántara, A. E., Zhu, C., Coffey, A. H., Michalek, L., Elabd, A., Gao, X., Chen, S., Xu, C., Yan, H., Jiang, Y., Wang, W., Peng, Y., Zeng, Y., Lyu, H., Moon, H., Bao, Z. 2023


    Carbon superstructures are widely applied in energy and environment-related areas. Among them, the flower-like polyacrylonitrile (PAN)-derived carbon materials have shown great promise due to their high surface area, large pore volume, and improved mass transport. In this work, we report a versatile and straightforward method for synthesizing one-dimensional (1D) nanostructured fibers and two-dimensional (2D) nanostructured thin films based on flower-like PAN chemistry by taking advantage of the nucleation and growth behavior of PAN. The resulting nanofibers and thin films exhibited distinct morphologies with intersecting PAN nanosheets, which formed through rapid nucleation on existing PAN. We further constructed a variety of hierarchical PAN superstructures based on different templates, solvents, and concentrations. These PAN nanosheet superstructures can be readily converted to carbon superstructures. As a demonstration, the nanostructured thin film exhibited a contact angle of ∼180° after surface modification with fluoroalkyl monolayers, which is attributed to high surface roughness enabled by the nanosheet assemblies. This study offers a strategy for the synthesis of nanostructured carbon materials for various applications.

    View details for DOI 10.1021/acsnano.3c05792

    View details for PubMedID 37668312

  • Neuromorphic sensorimotor loop embodied by monolithically integrated, low-voltage, soft e-skin. Science (New York, N.Y.) Wang, W., Jiang, Y., Zhong, D., Zhang, Z., Choudhury, S., Lai, J. C., Gong, H., Niu, S., Yan, X., Zheng, Y., Shih, C. C., Ning, R., Lin, Q., Li, D., Kim, Y. H., Kim, J., Wang, Y. X., Zhao, C., Xu, C., Ji, X., Nishio, Y., Lyu, H., Tok, J. B., Bao, Z. 2023; 380 (6646): 735-742


    Artificial skin that simultaneously mimics sensory feedback and mechanical properties of natural skin holds substantial promise for next-generation robotic and medical devices. However, achieving such a biomimetic system that can seamlessly integrate with the human body remains a challenge. Through rational design and engineering of material properties, device structures, and system architectures, we realized a monolithic soft prosthetic electronic skin (e-skin). It is capable of multimodal perception, neuromorphic pulse-train signal generation, and closed-loop actuation. With a trilayer, high-permittivity elastomeric dielectric, we achieved a low subthreshold swing comparable to that of polycrystalline silicon transistors, a low operation voltage, low power consumption, and medium-scale circuit integration complexity for stretchable organic devices. Our e-skin mimics the biological sensorimotor loop, whereby a solid-state synaptic transistor elicits stronger actuation when a stimulus of increasing pressure is applied.

    View details for DOI 10.1126/science.ade0086

    View details for PubMedID 37200416

  • Fast-Charging of Hybrid Lithium-Ion/Lithium-Metal Anodes by Nanostructured Hard Carbon Host ACS ENERGY LETTERS Gong, H., Chen, Y., Chen, S., Xu, C., Yang, Y., Ye, Y., Huang, Z., Ning, R., Cui, Y., Bao, Z. 2022; 7 (12): 4417-4426
  • High-brightness all-polymer stretchable LED with charge-trapping dilution. Nature Zhang, Z., Wang, W., Jiang, Y., Wang, Y., Wu, Y., Lai, J., Niu, S., Xu, C., Shih, C., Wang, C., Yan, H., Galuska, L., Prine, N., Wu, H., Zhong, D., Chen, G., Matsuhisa, N., Zheng, Y., Yu, Z., Wang, Y., Dauskardt, R., Gu, X., Tok, J. B., Bao, Z. 2022; 603 (7902): 624-630


    Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly basedon inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450candela per square metre), current efficiency (about 5.3candela per ampere) and stretchability (about 100per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.

    View details for DOI 10.1038/s41586-022-04400-1

    View details for PubMedID 35322250

  • Long-Range Proton Transport in Films from a Reflectin-Derived Polypeptide ACS Applied Materials & Interfaces Xu, C., et al 2021; 13 (18): 20938-20946

    View details for DOI 10.1021/acsami.0c18929

  • Stretchable Cephalopod‐Inspired Multimodal Camouflage Systems Advanced Materials Xu, C., Colorado Escobar, M., Gorodetsky, A. A. 2020; 32 (16)

    View details for DOI 10.1002/adma.201905717

  • Adaptive infrared-reflecting systems inspired by cephalopods Science Xu, C., Stiubianu, G. T., Gorodetsky, A. A. 2018; 359 (6383): 1495-1500

    View details for DOI 10.1126/science.aar5191