Biomimetic Eu@HOF Photoactivated Sponge as Ultrasensitive Auditory and Olfactory Sensor for Infrasound Wave Monitoring and Bimodal Information Integration

The combination of multisensory stimuli in the somatosensory system enables humans to understand object comprehensive characteristics and make precise judgments. However, the development of auditory-olfactory bimodal flexible biomimetic sensors (FBSs) to mimic the function of biological perception of external stimuli still presents complex challenges. Herein, an auditory-olfactory bimodal FBS (1 and 2) is fabricated based on hydrogen-bonded organic framework (Eu@HOF-BPTC) integrated with melamine sponge. During the auditory sensing process, 1 can monitor sound with a maximum response frequency of 400 Hz. The auditory FBS performs ultrahigh sensitivity (41335.995 cps Pa-1 cm-2), ultrahigh precision (relative standard deviation < 0.20%), ultrafast response time (20 ms), ultralow detection limit (1.1039 Hz and 0.1083 dB), and great recyclability (148 cycles), which can also real-time monitor infrasound waves within 4-20 Hz. Based on artificial intelligence, 2 as an olfactory FBS demonstrates excellent sensitivity with a ppm-level response limit and desirable selectivity toward four odor molecules and realizes wearable on-site detection. The FBS also completes auditory and olfactory signals integration and interoperability by means of human-machine interaction. The bimodal auditory-olfactory FBS is highly promising for implementing bimodal interaction, simulating complex biological neural system, and promoting environmental monitoring, disaster warning and health care.