Bioinspired Luminescent HOF-Based Foam as Ultrafast and Ultrasensitive Pressure and Acoustic Bimodal Sensor for Human-Machine Interactive Object and Information Recognition.

Abstract

Bionic sensors have extensively served smart robots, medical equipment, and flexible wearable devices. The luminescent pressure-acoustic bimodal sensor can be treated as a remarkable, multifunctional, integrated bionic device. Here, a blue-emitting hydrogen-bonded organic framework (HOF-TTA) as luminogen combines with melamine foam (MF), generating the flexible and elastic HOF-TTA@MF (1 and 2) as a pressure-auditory bimodal sensor. In the luminescent pressure sensing process, 1 has excellent maximum sensitivity (132.02 kPa^-1 ), low minimum detection limit (0.0 1333 Pa), fast response time (20 ms), high precision and great recyclability. 2 as a luminescent auditory sensor exhibits the highest response to the 520 Hz sound at 255-1453 Hz. In the process of sensing sound at 520 Hz, 2 possesses high sensitivity (1 648 441.3 cps Pa^-1  cm^-2 ), low detection limit (0.36 dB) and ultrafast response time (10 ms) within 11.47-91.77 dB. The sensing mechanisms toward pressure and auditory are analyzed in detail by finite element simulation. Furthermore, 1 and 2, as a human-machine interactive bimodal sensor, can recognize nine different objects and word information of "Health", "Phone", and "TongJi" with high accuracy and strong robustness. This work provides a facile fabricated method of luminescent HOF-based pressure-auditory bimodal sensors and endows them with new recognition functions and dimensions.