High-Resolution Mechanoluminescent Haptic Sensor via Dual-Functional Chromatic Filtration by a Conjugated Polymer Shell

Mechanoluminescence materials have emerged as promising candidates for haptic interface sensors due to their mechanically driven luminescent property. However, the inherently broad emission spectra of most mechanoluminescence materials hinder sharp signal generation and high spectral resolution. Here, a chromatic filtration strategy is suggested employing poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT) as a conjugated polymer shell on copper-doped zinc sulfide to achieve a highly refined and intensified signal. By selectively suppressing spectral components below 490 nm, the F8BT shell effectively narrows the emission bandwidth, yielding a full width at half maximum (FWHM) of 55 nm during the mechanoluminescence process. In particular, F8BT shell efficiently mitigates signal intensity loss, which can be ascribed to the chromatic filtration ability, through mechanoluminescence photon recycling performance. This dual functionality significantly reduces spectral noise in the blue region with high intensity, enhancing the resolution in actual powerless haptic controllers. The novel approach establishes a scalable framework for high-resolution mechanoluminescence platforms, providing a versatile pathway toward next-generation, power-free stress-sensing applications with unprecedented spectral precision and optical fidelity.