Mechanical-electrical optimization design for the highly sensitive and stable hybrid MXene electrode-based pseudocapacitive pressure sensor

Abstract

To achieve optimal performance of the flexible sensors, it is common to rely on a large number of trials rather than establishing models to predict or guide in a positive fashion. And in that sense, one has to spend a significant amount of time exploring process parameters, while the experimental results may contain a certain degree of randomness or unpredictability. Here, a mechanical–electrical optimization model is established to design the hybrid film coating thickness. The film coatings, to be specific, are achieved by crosslinking MXene nanosheets with holey reduced graphene oxide using cysteamine. And the coatings can be sprayed on the nickel foam as electrodes and be assembled to a pseudocapacitive pressure device. Through the combined analysis of the mechanical strength, adhesion force, and specific capacitance of the film, the model enables us to objectively evaluate and balance the working range and sensitivity of the device. Consequently, under the guidance of the designed model, the fabricated device with 500 nm thick electrodes exhibits a wide stable working range of 0–865 kPa that coincides with the theoretical prediction, in which the maximum sensitivity achieves to 156359 kPa−1. Ultimately, the sensitive device is used to collect boxing punches to demonstrate its ability to maintain stability during high-pressure repetitive testing, laying the foundation for analyzing and optimizing the striking techniques of athletes.