Triboluminescent Electrospun Mats with Blue-Green Emission under Mechanical Force

Abstract

Fibrous mechanosensing elements can provide information about the direction of crack propagation and the mechanism of material failure when they are homogeneously dispersed into the bulk volume of materials. A fabrication strategy of fibrous systems showing triboluminescent (TL) responses is in high demand for such applications. In this work, micrometer-sized Cu(NCS)(py) 2 (PPh 3 ) crystals were synthesized, and polymeric fibrous mats containing the TL crystals were obtained via electrospinning as a stress probe for the determination of mechanical impact. Four different polymeric systems have been employed (PMMA, PS, PU, and PVDF), and the mechano-optical sensing performance of electrospun mats of the polymer-crystal composites was measured. Photophysical properties (quantum yield, band gap, and broadness of the emission) of the TL crystal/electrospun mat composites were also studied. TL and PL emission maxima of the PU-based composite mat show identical behavior due to the chemical affinity between the two structures and the smallest fiber diameter. Moreover, the PU fiber mats exhibit long-lived bluish-green emission persisting over a large number of drops.

Triboluminescence of a new family of CuI–NHC complexes in crystalline solid and in amorphous polymer films

“…35 The emission maxima of TL spectra shi to longer wavelength compared to PL spectra, consistent with literature precedents. 24,[36][37][38] Representative images showing emission generated upon grinding crystals of 1, 2, and 3a are shown in Fig. 4, and a movie showing TL during grinding a crystalline sample or compression of a single crystal under air are given in the ESI.…”

“…[17][18][19][20][21][22][23] In all but one of these reports, however, no systematic experimental data were collected. 24 All of these reports are also examples of fractoluminescence, where a crystal is required to observe the TL effect.…”

Advances in Electrospun Fiber‐Based Flexible Nanogenerators for Wearable Applications

“…[46] The ability to produce 2D nanofibrous and 3D macrostructures with exceptionally long in length and uniform in diameter makes electrospinning one of the facile and very simple fiber fabrication technique. [47][48][49] Compared to the conventional fiber fabrication techniques, electrospinning permits the fabrication of nanofibers with enhanced surface area, controllable porosity, extremely long length, alignment on the molecular level, and lightweight nature which are needed for various fields [50] such as tissue engineering, [51,52] filtration, [53][54][55] functional materials in industrial applications, [56][57][58][59] sensors, [60][61][62] and energy harvesting applications. [63,64] The adventure of electrospinning dates back to 1934 with the revealing of the electrostatic spinning patent, which describes the production of polymer filaments using electrostatic repulsions of surface charges.…”

Polymeric Planar Microcavities Doped with a Europium Complex

“…Organometallic transition metal compounds are particularly attractive for the development of optical devices owing to their large quantum yield and chemical stability [1][2][3]. Among several of these compounds, europium tetrakis (dibenzoyl methide) triethylammonium (EuD 4 TEA) shows one of the most efficient emission processes [4][5][6].…”

“…Indeed, its structure consists of four coordinated electron donating groups (1,3-diphenyl-1,3-propanedione), which function as light absorbers; one is triethylamine, which serves to stabilize the complex, and the complexed emissive metal [8,9] (Figure 1). As mentioned above, the material shows an intense and sharp near-band-edge exciton emission at 614 nm, where the triboluminescence also occurs [3,10,11]. In spite of its outstanding emissive properties, EuD 4 TEA applications are currently limited to the sensing of mechanical stimulations using the pristine material, or embedding the material into polymer matrices such as poly methyl methacrylate [10].…”