Investigation on Characteristics of a MXenes-Based Air-Coupled Capacitive Ultrasonic Transducer Array

The sensitive membrane of capacitive ultrasonic transducers is quite crucial for their performances, which can affect sensitivity, bandwidth, acoustic impedance, etc. In this study, an air-coupled capacitive ultrasonic transducer array is proposed with sensitive materials of MXenes. The air-coupled ultrasonic array with a Ti3C2Tx diaphragm is designed and fabricated. The array is
$4\times4$
in size, with a membrane radius of 1 mm and a central frequency of 112.5 kHz. The simulation and experiments of the array are carried out to analyze the effect of the transducer characteristics by direct current (dc) bias voltages and alternating current (ac) excitation. The transmitting and receiving performance of the designed array are tested, and the results demonstrate that the array has outstanding sound pressure level (SPL) and receiving sensitivity. The feasibility of using Ti3C2Tx as a capacitive ultrasonic transducer diaphragm is indicated in this article, which expands the potential applications in acoustic measurement, detection, and imaging.