Clean Energy Storage and Artificial Intelligence
Advanced energy storage and brain-inspired computing technologies are of great importance for electric vehicles, grid-scale energy storage, and artificial intelligence. The representative energy storage technology and brain-inspired computing technology are Li-ion batteries and memristors, respectively. What is interesting to me is that the fundamental operating principles of these fascinating technologies are all based on ion transport in solid ceramics. Therefore, designing novel functional materials with ultrafast ion (i.e., Li+, Na+, O2-) transport capability is fundamental for future battery and electronic synapse applications. Over the past 10 years, I was dedicated to designing superionic solid electrolytes and addressing interfacial challenges of all-solid-state lithium batteries (ASSLBs). Meanwhile, I am keenly interested in electronic synapses (i.e., memristors) for neuromorphic computing.
Solid-State Electrolyte
A solid-state electrolyte is a core material for next-generation solid-state batteries, which requires high ionic conductivity, low electronic conductivity, wide electrochemical window, low cost, and good viability for large-scale manufacture. My research at the material level mainly covers solid-state oxide electrolytes, sulfide electrolytes, halide electrolytes, and polymer electrolytes, of particular interest to understanding the structure-to-property relationships via advanced characterizations, such as X-ray diffraction, X-ray absorption spectroscopy, neutron diffraction, and cryogenic electron microscopy (Cryo-EM).
Representative work:
(1) C. Wang‡, J. Liang‡, J. Luo, J. Liu, X. Li, F. Zhao, R. Li, H. Huang, S. Zhao, L. Zhang, J. Wang*, X. Sun*. A Universal Wet-Chemistry Synthesis of Solid-State Halide Electrolytes for High-Performance All-Solid-State Lithium Metal Batteries. Science Advances, 7, eabh1896 (2021). DOI: 10.1126/sciadv.abh1896.
Interface Design
Sluggish kinetics of interfacial ion and electron transport of all-solid-state batteries, which is originated mainly from detrimental interfacial reactions as well as insufficient solid-solid contact, significantly suppressed their electrochemical performance. Therefore, it is of the foremost importance to rationally design the interface and understand the root cause for performance decay.
Representative work:
(1) C. Wang‡, S. Hwang‡, M. Jiang‡, J. Liang, Y. Sun, K. Adair, M. Zheng, S. Mukherjee, X. Li, R. Li, H. Huang, S. Zhao, L. Zhang, S. Lu, J. Wang, C. V. Singh,* D. Su,* X. Sun*. Deciphering Interfacial Chemical and Electrochemical Reaction Mechanism of Sulfide-based All-Solid-State Batteries. Advanced Energy Materials, 2021, 11, 2100210.
All-Solid-State Pouch Cell
Not only fundamental understanding, but practical engineering of all-solid-state pouch cells is also indispensable for their commercial success, such as electrode engineering, ultrathin solid electrolytes, and high throughput manufacturing with a low cost.
Representative works:
(1) C. Wang‡, R. Yu‡, H. Duan‡, Q. Lu, Q. Li, K. Adair, D. Bao, Y. Liu, R. Yang, J. Wang*, S. Zhao*, H. Huang*, X. Sun*. Solvent-Free Approach for Interweaving Freestanding and Ultrathin Inorganic Solid Electrolyte Membranes, ACS Energy Letters, 2022, 7, 1, 410–416.
(2) C. Wang, J. Liang, Y. Zhao, M. Zheng, X. Li, X. Sun*. All-Solid-State Lithium Metal Batteries Enabled by Sulfide Electrolytes: from Fundamental Study to Practical Engineering Design. Energy & Environmental Science, 2021, 14, 2577-2619.
Electronic Synapse
Electronic synapses can emulate the brain’s plasticity with a much simpler structure and a lower fabrication cost than neurons based on silicon circuits, and with smaller energy consumption than traditional von Neumann computing methods. Therefore, electronic synapses are promising components of future neuromorphic systems.
Representative works:
(1) C. Wang‡, W. He‡, Y. Tong, R. Zhao*. Investigation and Manipulation of Different Analog Behaviors of Memristor as Electronic Synapse for Neuromorphic Applications. Scientific Reports. 2016, 6, 22970.
(2) C. Wang, W. He, Y. Tong, Y. Zhang, K. Huang, L. Song, S. Zhong, R. Ganeshkumar, R. Zhao*. Memristive Devices with Highly Repeatable Analog States Boosted by Graphene Quantum Qots, Small, 2017, 13, 1603435.