To pursuit the fast-visualization and portability of this luminescent probe, we further prepared a test paper by cohering the TDA-Tb powder with carbon paper (
Fig. 5A). The test paper exhibits strong green-yellow color luminescence, and the luminescence is quenched while encountered with MNZ, realizing a naked eye detectable sensing process. For comparation, the luminescence shows no change while treated with water, further confirms the MNZ sensing ability of the test paper (
Fig. 5B). Supporting the luminescence sensors onto membrane materials will endow them with good machinability and wide application range. Herein, flexible sensor TDA-Tb-M was prepared by incorporating TDA-Tb into a membrane material, which containing 1 mg of TDA-Tb, and 10 mg polymer (the polymer was consists of 90% mass ratio PVDF and 10% mass ratio PVA). The mechanical property of TDA-Tb-M is firstly tested because it is crucial for their practical application. As shown in
Fig. 5C, the TDA-Tb-M can be folded into "airplane" shape and recovered to its pristine shape without any damage on the membrane, and it can also be tailored into desired shapes such as "N K" (
Fig. 5D). The stress-strain test was further tested, and the maximum tensile stress of TDA-Tb-M can reach 5.6 MPa and its elongation is 12.5% (
Fig. 5E). These results suggest that the flexible sensor TDA-Tb-M has a good mechanical property. The flexible TDA-Tb-M can be fabricated to be "fluorescent skin" or portable device by pasting it onto human's body or easy-achieved carrier for realizing convenient and real-time MNZ detection. As shown in
Figs. 5F and G, the "fluorescent skin" and portable device possess good MNZ detection ability that obvious luminescence quenching can be observed after MNZ droplet was added onto their surfaces. Based on these results, the performance of TDA-Tb-M in luminescence detection of MNZ is further investigated. As shown in
Fig. 5H, the intense yellow light of TDA-Tb-M gradually turn to weak blue color and finally quenched with increasing the concentration (0–0.03 mmol/L) of MNZ. The change of luminescence color can be recognized by the color recognizer application of mobile phone, and the corresponding RGB values can be obtained (
Fig. 5I) [
41-
43]. As exhibited in the results, the ratio of G value to B value (G/B) of TDA-Tb-M gradually decreased with increasement of MNZ concentration, and the relationship between obtained G/B value
versus MNZ concentration follows the formula of
y = 4.6781 × exp(-x/0.0030) + 0.4520 (
Fig. 5J). According to this method, the concentration of MNZ can be easily and sensitively recognized by phone scanning. All in all, the TDA-Tb-M realized the convenient and visual detection of MNZ, which exhibits broad application prospects in the fields of luminescence detection. And this work firstly realized luminescent sensing method for MNZ detection without usage of luminescence spectrometer (Table S2 in Supporting information).