All-Printing Based, Capacitive Pressure Sensors on Paper
摘要
A fully printed, flexible capacitive pressure sensor was developed using standard desktop inkjet and laser printers on paper. The device consists of printed silver nanoparticle electrodes and a toner–silica nanoparticle composite dielectric layer. A unique microisland-like dielectric structure is formed during laser printing due to heterogeneous particle mixing and selective thermal fusion, resulting in rough surfaces with embedded air gaps. This morphology enhances sensitivity and accelerates response by allowing partial interlocking and compression under applied pressure. The sensor achieves a high sensitivity of 0.08 kPa−1 in the low-pressure range (< 30 kPa), fast response and recovery times (~ 50 ms), and maintains mechanical durability over 2000 loading cycles. A 144-pixel sensor array demonstrates scalability, and multifunctional input applications are enabled, including pressure-sensitive trackpads and keyboards where soft and hard touches correspond to distinct commands. This all-printing fabrication approach eliminates the need for microfabrication or complex post-processing, providing a cost-effective, scalable, and versatile method for flexible electronics. The printed pressure sensors offer a promising solution for next-generation human–machine interfaces and customizable paper-based electronic devices.
Graphical Abstract