A novel Zn(II) coordination polymer based on 5-(3pyridyl)-1,3,4-oxadiazole-2-thiol (Hpzt), namely [Zn(pzt) 2 ] n or Zn-CP, was synthesized by two different synthetic methods. The bulk polycrystals and single crystals of Zn-CP were obtained by a conventional solvothermal method at 90 °C. Zn-CP exhibits a two-dimensional (2D) coordination network that contains the uncoordinated Lewis basic sites within each layer. Interestingly, a simple and environmentally friendly sonochemical synthesis of the Zn-CP in an aqueous media could be performed at room temperature. The optimal synthetic conditions were studied. The uniform microplates of Zn-CP were obtained within 30 min with the addition of pyridine, acting as a size modulator and a deprotonating reagent. The influence of the amount of the modulator and the sonication time on the crystal size was investigated. Moreover, a Zn-CP suspension in an ethanolic media has been used as a luminescence sensor for the detection of nitroaromatic compounds. It shows highly selective and sensitive sensing of 2,4,6-trinitrophenol (TNP) through a quenching (turn-off) process under UV light. Also, the Zn-CP microplates show higher dispersibility and a more stable suspension in comparison to those of bulk products, causing an increase of the luminescent sensing performance for TNP.

Chromic materials have the potential to be used in a variety of applications, including memory devices and sensors. Despite fact that stimuli-responsive chromic materials have been widely reported to date, fabricating chromic materials that can be responsive to multiple external stimuli remains a challenge. Herein, a new multistimuli responsive chromic coordination polymer of {was successfully synthesized. Single-crystal X-ray diffraction analysis revealed that 1 exhibits a soft crystalline 3dimenional (3D) supramolecular framework generated by weakly interlayered stacking interactions between 2D coordination polymers. Compound 1 revealed unprecedented naked-eye mechanochromism, vapochromism, and thermochromism in response to multiple external stimuli including manual grinding, amine and alcohol vapors, and heat, respectively. The chromism related to the structural feature was clarified by SC-XRD, PXRD, TGA, elemental analysis, and spectroscopic techniques.

EDA Red shift d (0.0969, 0.0826) DEA Red shift d (0.2226, 0.1106) TEA Red shift d c [Cd(AS)2(phen)2]EtOH (1) vapor NH3 Blue shift ~85 (0.1834, 0.3330) This work EDA Blue shift ~54 (0.1399, 0.2042)

The use of vapor-responsive chromic materials in sensing applications for the detection of harmful volatile organic chemicals is rapidly expanding. Herein, four new amino-functionalized Cu­(I) coordination polymers of [CuI­(pyt-NH2)] n (1) and (2) and [CuSCN­(pyt-NH2)] n (3) and (4) (where pyt-NH2 = 2-amino-5-(4-pyridinyl)-1,3,4-thiadiazole) were successfully synthesized. Single-crystal X-ray diffraction analysis reveals that 1 and 2 are iodo-based polymorphs, while 3 and 4 are thiocyanato-based polymorphs. They possess densely diverse crystalline architectures decorated by uncoordinated amino groups as a binding site. Also, 1–4 show a variety of color and luminescence based on the structural diversity. Remarkably, 1 and 2 undergo the change of color and naked-eye solid-state luminescence in response to formaldehyde (FA) vapor, demonstrating simultaneous vapochromism and vapoluminescence. The chromic Cu­(I) coordination polymers in this work present for the first time dual-mode vapochromism and vapoluminescence in a highly selective response to FA vapor. The responsive mechanism has been clarified by Fourier transform infrared spectroscopy (FT-IR), electrospray ionization mass spectrometry (ESI-MS), 1H nuclear magnetic resonance (NMR), powder X-ray diffraction (PXRD), and luminescence lifetime measurements, which reveal carbinolamine formation via the specific reaction between FA and the active amino groups of coordinated pyt-NH2. The carbinolamine formation can trigger the structural transformation of 1 and 2, leading to the concurrently selective vapochromism and vapoluminescence induced by FA vapor.

We present a new intensely phosphorescent Pb(II) coordination polymer (1) containing a heteroatomic ligand. It has a quantum yield of 21.62% and a lifetime of 25.46 µs. The naked-eye solid-state...