A novel Li-ion based transistor within LiCoO2/Li6.75La3Zr1.5Ta0.5O12/Ag scheme

Traditional electronic devices are reaching their physical limits as they shrink in size to improve integration. Solid ionic devices have become promising candidate to avoid tunneling effect and address these constraints, but the response time are typically sluggish. In recent years, the rapid development of solid electrolyte and solid-state battery provide superior choices to overcome limitations in ion transport. In this work, we construct an ionic transistor within Ag/LiCoO₂/Li_6.75La₃Zr_1.5Ta_0.5O₁₂ (LLZTO)/Ag structure. LiCoO₂ serves as the channel layer of the transistor, with LLZTO acting as the electrolyte to isolate electrons and facilitate ion conduction, and Ag as the gate/anode. XRD, Raman spectroscopy, and electrochemical characterization confirm lithiation and delithiation. Transport characterization demonstrates the continuous resistive switching of the LiCoO₂ channel layer between high and low resistive states under pulsed gate voltage control, exhibiting high reversibility and long cycle stability. By combining X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES), the transition between high and low resistive states can be well clarified by a first-order Mott transition scheme. These results provide new perspectives for performance improvement and further development of ionic devices.