Sea Urchin-like Microstructures Pressure Sensors with Ultra-sensitivity and Super Working Range

Abstract Sensitivity and pressure range are two significant parameters of pressure sensors. The existing pressure sensors are difficult to achieve both high sensitivity and a wide pressure range. In this regard, we proposed a new pressure sensor with a ternary nanocomposite Fe2O3/C@SnO2. Notably, the sea urchin-like Fe2O3 structure promoted signal transduction and protected Fe2O3 needles from mechanical breaking; while, acetylene carbon black improved the conductivity of Fe2O3. Moreover, one part of SnO2 nanoparticles adhered to the surface of Fe2O3 needles and formed Fe2O3/SnO2 heterostructures whereas its other part of nanoparticles dispersed into the carbon layer and formed SnO2@C structures. Collectively, the synergy of the three structures (Fe2O3/C, Fe2O3/SnO2 and SnO2@C) improved the limited pressure response range of a single structure. The experimental results demonstrated that the Fe2O3/C@SnO2 pressure sensor exhibits high sensitivity (680 kPa-1), fast response (10 ms), broad range (up to 150 kPa), and good reproducibility (over 3500 cycles under a pressure of 110 kPa). This implies that the new pressure sensor has wide application prospects especially in wearable electronic devices and health monitoring.