Bioinspired HOF-based luminescent skin sensor with triple mechanochromism responses for the recognition and collection of human biophysical signals.

It is promising to develop luminescent force-sensitive bionic skin sensor (FBSS) with multiple mechanochromism (MC) responses for the sensing and collection of human biophysical signals. Herein, four bilayer hydrogen-bonded organic framework (HOF)-based polydimethylsiloxane (PDMS) elastic films (1-4) with full-color MC responses are fabricated by doping various luminescent HOF materials (HOF-TJ-1, R, Y, and G) into different PDMS layers. 1-4 as luminescent FBSSs possess stretched-, bended-, and pressed-MC properties. In stretching and bending processes, the color-switching performances of 1-4 are from initial blue to red, yellow, and green, and 4 exhibits an increased blue emission. Under pressing strain of 0-40%, the blue emission of 1-4 is strengthened. In stretched-, bended-, and pressed-MC processes, 1-4 show ultralow detection limits and excellent recyclability with 6000, 20 000, and 10 000 times, respectively. The MC mechanisms in stretched, bent, and pressed processes are investigated in depth