The ferroelectric ceramic/elastomer composite as the dielectric coating of soft capacitive neural interface: The competitive effects of ceramic particles

Capacitive neural interface provides a safer way to record the neural activity with reduced risk of current leakage and improved biocompatibility. The emerging of soft neural interfaces makes it necessary to propose dielectric coating with excellent flexibility and dielectric property for the soft capacitive neural interface. In this study, the feasibility and strategy of using the ferroelectric ceramic/elastomer composite as the dielectric coating in soft capacitive neural interface are discussed. With excellent electrical isolation performance, the device experimentally demonstrates the abilities to record in vivo electrocorticogram signal with comparable quality to the commercial electrode and steady-state visual evoked potential signal with improved signal-to-noise ratio. The roles of the ceramic particles in the performance of soft capacitive neural interface are discussed by evaluating the influences of composite content on not only the permittivity but the wettability and stiffness of the dielectric coating, providing the understanding for using the elastomer-based composite as the dielectric coating of the soft capacitive neural interface in a broader view.