Mechanoluminescence And Photoluminescence Heterojunction for Superior Multi-mode Sensing Platform of Friction, Force, Pressure And Temperature in Fibers And 3D-printed Polymers.

Endowing a single material with various types of luminescence, i.e., exhibiting a simultaneous optical response to different stimuli, is vital in various fields. A photoluminescence (PL)- and mechanoluminescence (ML)-based multifunctional sensing platform was built by combining heterojunctioned ZnS/CaZnOS:Mn 2+ mechano-photonic materials using a 3D-printing technique and fiber spinning. ML-active particles were embedded in micron-sized cellulose fibers for flexible optical devices capable of emitting light driven by mechanical force. We also fabricated individual modified 3D-printed hard units that exhibit intense ML in response to mechanical deformation such as impact and friction. Importantly, they also allow low-pressure sensing up to ∼100 bar, a range previously inaccessible by any other optical sensing technique. Moreover, the developed optical manometer based on the PL of the materials demonstrates a superior high-pressure sensitivity of ∼6.20 nm/GPa. Using this sensing platform, four modes of temperature detection can be achieved: excitation- and emission-band spectral shifts, bandwidth broadening and lifetime shortening. Our work supports the possibility of mass production of ML-active mechanical and optoelectronic parts integrated with scientific and industrial tools and apparatus. This article is protected by copyright. All rights reserved.