Abstract
In this study, the flexible PDMS substrates are coated with zinc oxide and zinc oxide doped with aluminum films respectively as seed layers. And the aqueous solution method is used to synthesize one-dimensional zinc oxide nanorods. Then, the PDMS substrates with zinc oxide nanorods are combined to make a multifunctional piezoresistive tactile sensors for artificial electronic skins. The growth solution with aqueous solution method are mixed by dissolving the zinc nitrated and hexamethylenetetramine in the deionized water in a 1:1 ratio. The reaction temperature of solution is 95 degrees for zinc oxide seed layers and 90 degrees for zinc oxide doped with aluminum seed layers, and the reaction time of solution is 10 hours. Then successfully synthesized the high quality and high aspect ratio one-dimensional zinc oxide nanorods on PDMS substrates. Crystal structure and growth morphology of zinc oxide nanorods were investigated by X-ray power diffractometer and field emission scanning electron microscopy respectively, and energy-dispersive X-ray spectroscopy was used to analyze the composition of Zinc oxide nanorods. The two PDMS substrates with zinc oxide nanorod arrays as the upper and lower electrode were combined each other to form interlocked structure by zinc oxide nanorods. In this interlocked geometry, an applied pressure induces a change in the contact area between interlocked zinc oxide nanorods, thus changing the contact resistance. In addition, the semiconductor thermal properties of zinc oxide can be applied to detect environmental temperature. The flexible multifunctional tactile sensor may find applications such as artificial electronic skins, artificial prosthetics, and wearable devices.