Activation of percolation network in structural-strengthened polymer-derived ceramic for minor deformation detection

Monitoring of minor deformation in precision instruments is of great significance to guarantee the reliable operation. Polymer derived ceramic sensors with superior piezoresistive performance are promising. The traditional forming methods of the PDC sensor may cause the decline in mechanical properties. Thus, a silicon oxycarbide (SiOC) ceramic pressure sensor with diamond minimal surface structure were designed to improve the dimensional stability and ensure the uniform distribution of the stress. The percolation network comprising of electrically conductive free carbon was formed in the SiOC by the post heat treatment, which provided the structure superior piezoresistive property. The customized percolation network provided tunable sensing behavior and the resulting sensor had excellent accuracy and repeatability, possessing high sensitivity with the gauge factor of 297. More importantly, the sensor exhibited the high sensitivity with the small strains lower than 1.5%, indicating a reliable detection ability to the easily overlooked deformation. Additionally, the sensor had a high conductivity of 1.05 S/m and outstanding mechanical properties with the compressive strength and energy absorption of 15.11 MPa and 71.39 kJ•m⁻³. The printed sensor surmounts the limitations of current sensing materials, providing a promising way for the fabrication of high-performance and customized polymer derived ceramic pressure sensor.