Two-stage amplification of an ultrasensitive MXene-based intelligent artificial eardrum

Abstract

We report an artificial eardrum using an acoustic sensor based on two-dimensional MXene (Ti 3 C 2 T x ), which mimics the function of a human eardrum for realizing voice detection and recognition. Using MXene with a large interlayer distance and micropyramid polydimethylsiloxane arrays can enable a two-stage amplification of pressure and acoustic sensing. The MXene artificial eardrum shows an extremely high sensitivity of 62 kPa −1 and a very low detection limit of 0.1 Pa. Notably, benefiting from the ultrasensitive MXene eardrum, the machine-learning algorithm for real-time voice classification can be realized with high accuracy. The 280 voice signals are successfully classified for seven categories, and a high accuracy of 96.4 and 95% can be achieved by the training dataset and the test dataset, respectively. The current results indicate that the MXene artificial intelligent eardrum shows great potential for applications in wearable acoustical health care devices.

Electrically Tunable MXene Nanomechanical Resonators Vibrating at Very High Frequencies

“…These values are comparable with some of the best MXene pressure transducers, including those 19 with two-stage signal amplification (10 −1 Pa and 62 kPa −1 ). It is worth noting that while MXene pressure sensors and transducers 18,19,66 have been extensively studied, most of these devices work in ambient conditions. Therefore, the fine pressure sensing potential in vacuum environment demonstrated in our MXene resonators nicely complements these sensors functioning under higher pressure (such as 1 atm) for detecting larger pressure changes (such as sound waves or physical touches).…”

“…65 Our data show that the MXene gauge can function at pressure as low as 1.65 × 10 −4 Torr (2.2 × 10 −2 Pa) with a responsivity (slope of the curve) of 736%/Torr (55 kPa −1 ) (see Supporting Information text), demonstrating the excellent sensing potential of MXene-based NEMS devices. These values are comparable with some of the best MXene pressure transducers, including those 19 with two-stage signal amplification (10 −1 Pa and 62 kPa −1 ). It is worth noting that while MXene pressure sensors and transducers 18,19,66 have been extensively studied, most of these devices work in ambient conditions.…”

“…Two-dimensional (2D) transition metal carbides and nitrides, also known as MXenes, , have been attracting increasing research interest due to their intriguing electrical, optical, thermal, and mechanical properties. − While applications such as lubrication, electrocatalysis, wear resistance, and energy storage/harvesting , have been extensively explored, MXene materials have also demonstrated exciting potential toward device applications such as transistors, sensors, − actuators, photodetectors, optical modulators, memories, and artificial synaptic devices …”

Applications of MXenes in human-like sensors and actuators

“…Nanostructured materials may improve the performance of acoustic membranes. Acoustic sensors made of graphene [164] and carbon nanotubes [165] have been reported to detect human voices and recognize speech assisted with deep data learning.…”

Graphene-based strain sensor with sandwich structure and its application in bowel sounds monitoring

“…Moreover, the suspended SFG designed by Qiao et al exhibited good acoustic detection skills, 56 and the MXene nanoflakes-based artificial eardrum designed by Gou et al had excellent acoustic sensing ability. 57 Therefore we believe that the strain sensor containing graphene nanoplatelets can monitor intestinal movement and make an accurate and objective.…”