Detection Range Enhanced Highly Sensitive Niobate Nanosheet Pressure Sensors by Optimization of Substrate and Electrode Materials

With the widespread application of flexible pressure sensors in various fields, the demand for developing high-performance flexible pressure sensors is increasing. Two-dimensional oxide pressure sensors (2DOPSs) hold immense potential due to their ultra-high sensitivity. However, further improving the overall performance of the device remains a challenge for 2DOPSs, especially to widen the pressure sensing range of the sensor. In this article, the effect of substrate and electrode materials on the performance of the Ca₂Nb₃O₁₀ nanosheet pressure sensors is investigated. It is found that the lower the Rockwell hardness of the electrodes of the device, the easier the substrate material deforms under pressure, and the lower the device pressure threshold, the higher the sensitivity. The optimization of the substrates and electrodes yields Ca₂Nb₃O₁₀ nanosheet pressure sensors with sensitivity up to 10⁵ kPa⁻¹ in a large detection range, fast response time (83/165 ms) and good stability. This work provides guideline for further development of 2DOPSs.