A luminescent ytterbium(III)-organic framework for highly selective sensing of 2,4,6-trinitrophenol

Author’s Accepted Manuscript A Luminescent Ytterbium(III)-Organic Framework for Highly Selective Sensing of 2,4,6Trinitrophenol Xuelian Xin, Minghui Zhang, Shijie Ji, Hanxiao Dong, Liangliang Zhang www.elsevier.com/locate/yjssc

PII: DOI: Reference:

S0022-4596(18)30085-9 https://doi.org/10.1016/j.jssc.2018.03.007 YJSSC20133

To appear in: Journal of Solid State Chemistry Received date: 29 December 2017 Revised date: 11 February 2018 Accepted date: 6 March 2018 Cite this article as: Xuelian Xin, Minghui Zhang, Shijie Ji, Hanxiao Dong and Liangliang Zhang, A Luminescent Ytterbium(III)-Organic Framework for Highly Selective Sensing of 2,4,6-Trinitrophenol, Journal of Solid State Chemistry, https://doi.org/10.1016/j.jssc.2018.03.007 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

A Luminescent Ytterbium(III)-Organic Framework for Highly Selective Sensing of 2,4,6-Trinitrophenol Xuelian Xin1, Minghui Zhang2, ShijieJi2, Hanxiao Dong2, Liangliang Zhang2,* 1

College of Public Health & Key Laboratory of Medicinal Chemistry and Molecular

Diagnosis, Ministry of Education, Hebei University, No. 342 Yuhuadonglu, Baoding 071000, China; 2

State Key Laboratory of Heavy Oil Processing & College of Science, China

University of Petroleum (East China), Qingdao, Shandong, 266580, China.

* Corresponding authors: E-mail addresses: [email protected] (L. Zhang). Abstract An ytterbium(III)-organic framework, [Yb4(abtc)3(HCOO) (H2O)]·(C2H8N) (H2O) (UPC-22, H4abtc = 3,3ʹ ,5,5ʹ -azobenzene-tetracarboxylic acid) was synthesized under solvothermal conditions and characterized. UPC-22 exhibited strong H4abtc-based luminescence and can be used for sensing nitroaromatic compounds (NACs) in an ethanol suspension with outstanding selectivity and sensitivity. The most

striking

property

of

UPC-22

is

its

ability

to

selectively

detect

2,4,6-trinitrophenol (TNP), thereby rendering it a promising TNP-selective luminescence probe. Graphical abstract Graphical abstract

1

Keywords: ytterbium(III) -organic framework; luminescent metal-organic framework; sensor; 2,4,6-trinitrophenol

1. Introduction Nitroaromatic compounds (NACs), which are a class of dynamites, have attracted growing attention in recent years because of their facile fabrication, low cost, and widespread application in military engineering and blast engineering [1–5]. In particular, 2,4,6-trinitrophenol (TNP), which exists as yellow crystals and exhibits a strong bitter taste, is highly explosive. Exposure to TNP can lead to skin discoloration (yellowness), contact dermatitis, conjunctivitis, and bronchitis [6–9]. In the context of NACs detection in raw materials and reagents for the syntheses of pharmaceuticals, dyes, and explosives, techniques such as cyclic voltammetry, Raman spectroscopy, and gas chromatography are commonly employed [10–11], but those methods tend to be expensive and tedious. As such, fluorescent sensing materials have been considered as promising candidates for the detection of NACs because of their high selectivity, outstanding sensitivity, and portability [12–14]. Nevertheless, the 2

development of convenient and highly efficient NACs detection methods remains a challenge. Metal-organic frameworks (MOFs), which comprise metal ions or metal clusters and organic ligands, have received growing attention from scientists in the fields of chemistry and materials science, mainly due to their unique structural characteristics and properties, such as their easily modifiable skeletons and high specific surface areas [15–17]. MOFs have the characteristics of both organic ligands and metal ions (or metal clusters), and show better thermal stability over organic ligands through coordination [18–22]. These superior properties render MOFs suitable for a range of applications, including fluorescence recognition, gas adsorption/separation, catalysis, and as magnetic materials. In this context, the fluorescence characteristics of MOFs are strongly dependent on the type of metal ion/cluster and organic ligands, the electron transfer mechanisms, and the presence of luminous units [23–27]. More specifically, in 2009, Li et al. designed and synthesized a luminescent functional MOF, which exhibited a fast response to explosives in the vapor phase. Subsequently, a series of luminescent MOFs were reported for using as fluorescent sensors for NACs. For example, Pandey et al. reported a novel binuclear Zn(II) complex that can recognize TNP at the ppb level [28], while Rachuri et al. synthesized a Cd(II) MOF for the detection of TNP with a detection limit of 62 ppb [29]. Furthermore, Jia et al. presented a stable fluorescent MOF that could selectively detect TNP with a quenching coefficient of 2.08 × 106 M−1 [30], while Zheng et al. reported two luminescent Cd(II)/Zn(II)-based MOFs as fluorescent sensors for TNP [31]. 3

Thus, we herein report the preparation and characterization of an ytterbium(III)-organic framework, namely , [Yb4(abtc)3(HCOO) (H2O)]·(C2H8N) (H2O) (UPC-22, H4abtc = 3,3ʹ ,5,5ʹ -azobenzene-tetracarboxylic acid), followed by studies into its potential application in the selective and sensitive detection of NACs, and in particular TNP. 2. Experimental section 2.1. Materials and general methods All chemicals and solvents were purchased and used as received without further purification. The single crystal X-ray data was collected on an Agilent Xcalibur Eos Gemini diffractometer with Cu-Kα radiation (λ = 1.54178 Å) at 107 K. Contributions to scattering from all solvent molecules were removed using the SQUEEZE routine of PLATON [32]. Elemental analyses (C, H, and N) were performed on a CE instrument EA 1110 elemental analyzer. Thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC) experiments were carried out on a Mettler Toledo TGA instrument with a heating rate of 10 oC min−1 in the range of 25 – 800 oC under a N2 atmosphere. The powder X-ray diffraction data was obtained on a Philips X’ Pert with Cu-Kα radiation (λ = 0.15418 nm), and the recording speed was 5° min−1 over the 2θ range of 5–50° at room temperature. Fourier transform infrared spectroscopy (FTIR) spectra were collected on a Bruker VERTEX-70 spectrometer in the 4000 − 400 cm−1 region. The absolute fluorescence quantum yields were measured with an integrating sphere on an Edinburgh Instruments FLS920 three-monochromator spectrophotometer. The optical absorption spectra were measured on a UV-vis spectrometer (Specord 205, 4

Analytik Jena) in the range of 220 to 500 nm. 2.2. Luminescent experiments All luminescent measurements were carried out at room temperature on a Hitachi F7000 luminescence spectrophotometer. Samples in solid state were excited at 330 nm with the excitation and emission slit widths set at 20 and 10 nm, respectively. Samples for NACs detection were excited at 330 nm with the excitation and emission slit widths set at 20 and 10 nm, respectively. Samples for metal ions detection were excited at 330 nm with the excitation and emission slit widths set at 10 and 10 nm, respectively. The emission spectra were scanned from 350 to 700 nm with 1200 nm min−1. The photomultiplier voltage was set at 400 V. Accordingly, the probe was dispersed in ethanol (EtOH) to make a 1 mg·mL−1 dispersion and the added substances were dissolved in EtOH as well. 2.3. Synthesis of UPC-22 UPC-22 was initially synthesized via a solvothermal reaction by Yb(NO3)3·6H2O, H4abtc, and HNO3 in a mixture solvent containing dimethyl formamide (DMF), ethanol (EtOH), and H2O (in a 5:2:1 volume ratio). Followed by heating at 120 °C for 3600 min in a sealed tube and filtration, the desired orange crystal products were obtained, washed with DMF, H2O, and EtOH and dried at 60 °C under reduced pressure over 3 h to afford UPC-22 with yield of 65% based on Yb. The identity of this product was further confirmed by elemental analysis, fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) experiments (Figs. S1–S2). The TGA curve shows a weight loss of 5

2.7 % from 41 to 265 oC corresponding to the loss of lattice H2O molecules (calcd: 2.8%). Then, UPC-22 starts to decompose above 265 oC. Anal. Calcd for UPC-22: C, 31.41; H, 1.45; N, 4.49. Found: C, 31.49; H, 1.59; N 4.42%. IR (KBr, cm–1): 3399 m, 3078 m, 2931 m, 2849 m, 2499 w, 1911 w, 1663 s, 1611 s, 1594 s, 1548 vs, 1450 s, 1408 s, 1383 vs, 1235 m, 1100 m, 922 w, 787 s, 715 s, 519 m, 493 m. 3. Results and discussion 3.1. Structural descriptions X-ray single crystal diffraction experiments reveal that UPC-22 is an anionic three-dimensional MOF which crystallizes in the monoclinic space group C2/c. The crystallographic data are listed in Table 1, and selected bond distances and angles are given in Tables S1 and S2, respectively. From these data, we determined that UPC-22 contains two types of central Yb ions, namely Yb1 and Yb2. Each 8-coordinate Yb1 ion is coordinated to six oxygen atoms originating from five H4abtc ligands, and an oxygen atom from formic acid (derived from the decomposition of the solvent, DMF [33–34]), and an oxygen atom from H2O. In contrast, each 7-coordinate Yb2 ion is coordinated to seven oxygen atoms originating from five H4abtc ligands. In addition, all carboxylic groups of the H4abtc ligand are deprotonated, three of which form bidentate bridges to link two Yb ions, while the fourth chelates to a single Yb ion (Fig. 1a). Moreover, the Yb1 and Yb2 ions are connected by H4abtc ligands, and the adjacent Yb2 ions are connected by a formic acid moiety. The one-dimensional infinite chains are further linked by the H4abtc ligands (Fig. 1b) to generate the three-dimensional UPC-22 porous framework (Fig. 1c) in which large quantities of 6

uncoordinated dimethylamine cations (C2H8N+, produced by DMF decomposition [33–34]), DMF, EtOH, and H2O molecules reside [32, 35]. If we regard the H4abtc ligands as four spacers and Yb(III) ions as five spacers, the topology of UPC-22 can be

thought

as

4,5,8-connected

net

with

the

point

symbol

of

{3.47.52}2{32.49.59.68}2{44.62} (Fig. 1d). The experimental powder PXRD pattern is almost identical to corresponding simulated one, indicating the phase purity (Fig.S3). 3.2. Luminescent properties The luminescence emission spectra of H4abtc (Φ = 0.31) and UPC-22 (Φ = 0.15) were then measured in the solid state at room temperature, as shown in Fig. S4. As indicated, the free ligand and UPC-22 exhibited emission maxima at 438 and 506 nm (λex = 330 nm), respectively. The luminescence emission peak of the H4abtc free ligand could be attributed to π*-π transitions, while the red-shifted peak of UPC-22 could be attributed to π*-π transitions associated with metal coordination. These luminescence properties of UPC-22 were exploited for the luminescence sensing of NACs and metal ions. Thus, samples of UPC-22 were ground and suspended in a range of solvents (i.e., H2O, methanol, EtOH, dimethyl sulfoxide, and petroleum ether), and the luminescence properties of the resulting mixtures were measured (Fig. S5). However, due to the demands of green chemistry and the necessity for high solubility, the luminescence properties of UPC-22 were further investigated by dispersing the MOF in EtOH (specific details can be found in S8). 3.3. Detection for NACs To further explore the sensing ability of UPC-22 towards different NACs 7

(including nitrobenzene (NB), 1,3-dinitrobenzene (1,3-DNB), 2,4-dinitrotoluene (2,4-DNT), 1,4-dinitrobenzene (1,4-DNB), 4-nitrophenol (4-NP), 4-nitrotoluene (4-NT), and 2,4,6-trinitrophenol (TNP)), solutions of these compounds in EtOH (1 mM) were added gradually to suspensions of UPC-22 in EtOH, and the fluorescence changes were monitored by fluorescence spectroscopy. As indicated in Fig. S6, the presence of NACs weakened the emission intensity of the UPC-22 suspension with varying degrees (I−I0/I). More specifically, the introduction of TNP and 4-NP led to significant fluorescence quenching (i.e., ~95 and ~82%, respectively, see Figs. 2a–2b, S7), while the addition of NB, 1,3-DNB, 2,4-DNT, 1,4-DNB, and 4-NT resulted in only minor spectral changes (the full spectra are shown in Fig. S8). It is worth noting that upon the incremental addition of TNP to the UPC-22 suspension, a prominent redshift of 57 nm (418 to 475 nm) was observed, thereby rendering this system an effective probe compared to other reported systems [1]. For comparison, titration experiments performed using phenol /UPC-22 and NACs/H4abtc mixtures were also carried out (see Figs. S8 and S9). In this case, the incremental addition of TNP to a suspension of the H4abtc ligand produced similar quenching and redshift as UPC-22, indicating that the sensing properties result from interactions between the TNP and the ligand. Compared to H4abtc ligand, as a MOF, UPC-22 showed better the thermal stability of organic ligands through coordination and broadened the application range of organic ligands with special functions [18–22]. These results confirm that UPC-22 shows high sensitivity towards TNP, thereby explaining the remarkable red shift of the luminescence emission peaks and the apparent 8

luminescence “turn-off” response. To gain a deeper insight into the interactions between UPC-22 and the NACs, UV-Vis spectra of the various mixtures were recorded (Figs. S10 and S11). Upon the addition of different NACs, the obtained absorption spectra were comparable to those of the pure compounds, indicating that dynamic fluorescence quenching took place. This quenching mechanism likely involves electron transfer from the H4abtc ligands to the electron-deficient NACs [20]. The fluorescence quenching efficiency was then calculated using the Stern-Volmer (SV) equation: (I0/I) = Ksv [A] + 1, where I0 and I are the fluorescence intensities before and after the addition of the analytes, respectively, [A] is the molar concentration of the analyte, and Ksv is the quenching coefficient. Thus, the fluorescence quenching rates of TNP and 4-NP on UPC-22 were 5.5×104 and 0.65×104 M−1 (Figs. 2c, and 2d), respectively. In addition, the quenching efficiencies of the various NACs in EtOH followed the order: TNP > 4-NP >> 1,4-DNB > 1,3-DNB > 2,4-DNT > 4-NT > NB (Fig. 3), indicating the high selectivity of UPC-22 towards TNP. To examine the stability of UPC-22 in the presence of the NACs, powder X-ray diffraction (PXRD) experiments were carried out. As depicted in Fig. 4, the UPC-22 framework (after soaked in 1 mM EtOH solutions of the NACs for 24 h, and the solid was filtered and dried for the PXRD experiments.) remained intact. These results confirmed that UPC-22 can indeed be applied as a fluorescent sensor for the detection of TNP with high sensitivity and selectivity. 3.4. Detection for Al3+ cations 9

Finally, to examine the potential of UPC-22 for sensing metal ions, EtOH solutions containing a range of metal ions (i.e., Li+, Na+, Ag+, Cu2+, Zn2+, Ca2+, Ni2+, Cr3+, and Al3+) were added gradually to suspensions of UPC-22 in EtOH. However, the majority of these metal ions had little influence on the luminescence intensity of the original suspension. Indeed, the luminescence intensity of the suspension at 430 nm varied only slightly in the presence of Li +, Na+, Ag+, Cu2+, Zn2+, Ca2+, Ni2+, and Cr3+, but increased significantly in the presence of Al3+ (Figs. S12 and S13). Furthermore, in the corresponding UV-Vis spectra (Fig. S14 and S15), a new absorption band was observed only upon the addition of Al3+ at a longer wavelength. It is widely acknowledged that the exible geometry of Al3+ is a result of the fact that it can exist in a variety of coordination environments. This may be ascribed to the interaction of Al3+ with the N=N atoms of UPC-22 through d–d transition. The results indicated the presence of interactions between Al3+ and UPC-22 [36–39]. PXRD experiments were also performed to examine the stability of UPC-22 in the presence of metal ions. As depicted in Fig. S16, after soaking in solutions of EtOH containing the different metal ions (1 mM, 24 h) the UPC-22 framework remained unchanged, demonstrating that UPC-22 can also selectively and stably detect Al3+ through fluorescence enhancement. 4. Conclusion In

conclusion,

a

multifunctional

ytterbium(III)-organic

framework,

,

[Yb4(abtc)3(HCOO) (H2O)]·(C2H8N) (H2O) (UPC-22), was successfully synthesized and characterized. In the solid state, UPC-22 exhibited strong H4abtc-based 10

luminescence emission, whilst in an ethanol suspension, UPC-22 was suitable for the detection of 2,4,6-trinitrophenol (TNP) with outstanding selectivity and sensitivity. The most striking properties of UPC-22 are the distinct red shift (57 nm) and fluorescence quenching observed in the presence of TNP, which render it a promising TNP-selective luminescent probe. Additionally, UPC-22 exhibits excellent selectivity in the sensing of Al3+ through fluorescence enhancement. Acknowledgements This work was supported by the NSFC (21701187), Special Fund for 2017 “one province and one university” of Hebei University.

Supporting information

Materials, physical measurements, and fluorescent experiments; selected crystallographic data (CIF) of UPC-22; PXRD, TGA/DSC, luminescence emission spectra, and UV-Vis spectra.

Reference:

[1] L. Zhang, Z. Kang, X. Xin, D. Sun, CrystEngComm 18 (2016) 193−206. [2] W. Sun, J. Wang, H. Liu, S. Chang, X. Qin, Z. Liu, Mater. Lett. 126 (2014) 189−192. [3] X.H. Zhou, L. Li, H. H. Li, A. Li, T. Yang, W. Huang, Dalton Trans. 42 (2013) 12403−12409. [4] M.E. Germain, M.J. Knapp, Chem. Soc. Rev. 38 (2009) 2543−2555. [5] T. Wen, D.X. Zhang, Q.R. Ding, H.B. Zhang, J. Zhang, Inorg. Chem. Front. 1 (2014) 389−392. [6] J. Ye, L. Zhao, R.F. Bogale, Y. Gao, X. Wang, X. Qian, S. Guo, J. Zhao, G. Ning, Chem.-Eur. J. 21 (2015) 2029−2037. [7] S.S. Nagarkar, A.V. Desai, P. Samanta, S.K. Ghosh, Dalton Trans. 44(2015) 15175−15180. 11

[8] P. Ghosh, P. Banerjee, Anal.Chim.Acta 965 (2017) 111−122. [9] Z. Zhang, S. Chen, R. Shi, J. Ji, D. Wang, S. Jin, T. Han, C. Zhou, Q. Shu, Talanta 166 (2017) 228−233. [10]S. Pramanik, C. Zheng, X. Zhang, T.J. Emge, J. Li, J. Am. Chem. Soc. 133 (2011) 4153−4155. [11] A.X. Zhu, Z.Z. Qiu, L.B. Yang, X.D. Fang, S.J. Chen, Q.Q. Xu, Q.X. Li, CrystEngComm 17 (2015) 4787−4792. [12] F. Drache, V. Bon, I. Senkovska, M. Adam, A. Eychmüller, S. Kaskel, Eur. J. Inorg Chem. 2016 (2016) 4483−4489. [13] V. Mahendran, K. Pasumpon, S. Thimmarayaperumal, P. Thilagar, S. Shanmugam, J. Org. Chem. 81 (2016) 3597−3602. [14] X.L. Qu, D. Gui, X.L. Zheng, R. Li, H.L. Han, X. Li, P.Z. Li, Dalton Trans. 45 (2016) 6983−6989. [15]D. Feng, K. Wang, Z. Wei, Y.P. Chen, C.M. Simon, R.K. Arvapally, R. L. Martin, M. Bosch, T.F. Liu, S. Fordham, D. Yuan, M.A. Omary, M. Haranczyk, B. Smit, H.C. Zhou, Nat.Commun. 5 (2014) 5723. [16] W. Wang, J. Yang, R. Wang, L. Zhang, J. Yu, D. Sun, Cryst. Growth Des. 15 (2015) 2589−2592. [17] R.D. Mukhopadhyay, V.K. Praveen, A. Hazra, T.K. Maji, A. Ajayaghosh, Chem. Sci. 6 (2015) 6583−6591. [18]A.M. Nonat, C. Allain, S. Faulkner, T. Gunnlaugsson, Inorg. Chem. 49 (2010) 8449–8456. [19]L.H. Cao, F. Shi, W.M. Zhang, S.Q. Zang, T.C.W. Mak, Chem. Eur. J. 21 (2015) 15705 –15712. [20]H.C. Zhou, J.R. Long, O.M. Yaghi, Chem. Rev. 112 (2017) 673−674. [21]J.R. Long, O.M. Yaghi, Chem. Soc. Rev. 38 (2009) 1213−1214. [22]Wang F., Z. Yu, C. Wang, K. Xu, J. Yu, J. Zhang, Y. Fu, X. Li, Y. Zhao, Sensor Actuat B: Chem. 239 (2017) 688−695. [23]G.X. Wen, Y.P. Wu, W.W. Dong, J. Zhao, D.S. Li, J. Zhang, Inorg. Chem. 55 (2016) 10114–10117. [24]T. Wen, D.X. Zhang, J. Liu, H.X. Zhang, J. Zhang, Chem. Commun. 51 (2015) 1353−1355. [25] Y.J. Cui, Y.F. Yue, G.D. Qian, B.L. Chen, Chem. Rev. 112 (2012) 1126−1162. [26] Z.C. Hu, B.J. Deibert, J. Li, Chem.Soc.Rev. 43 (2014) 5815−5840. [27] F. Wang, W. Liu, S.J. Teat, F. Xu, H. Wang, X. Wang, L. An, J. Li, Chem.Commun. 52 (2016) 10249−10252. [28] A. Kumar, A. Kumar, D.S. Pandey, Dalton Trans. 45 (2016) 8475−8484. [29] Y. Rachuri, B. Parmar, K.K. Bisht, E. Suresh, Dalton Trans. 45 (2016) 7881−7892. [30] X.X. Jia, R.X. Yao, F.Q. Zhang, X.M. Zhang, Inorg.Chem. 56 (2017) 2690−2696. [31] H. Xu, H.G. Zheng, Inorg. Chem. Commun. 66 (2016) 51−54. [32]F.L. Liu, Y.W. Xu, L.M. Zhao, L.L. Zhang, W.Y. Guo, R.M. Wang, D.F. Sun, J. Mater. Chem. A 3 (2015) 21545–21552. 12

[33]C.X. Wang, X.M. Zhou, W.Y. Shi, Acta Crystallographic. Sect. E 63 (2007) 411 −412. [34]K. He, Z. Cao, R.R. Liu, Y. Miao, H.Y. Ma, Y. Ding, Nano Res. 9 (2016) 1856– 1865. [35]R.M. Wang, X.B. Liu, A. Huang, W. Wang, Z.Y. Xiao, L.L. Zhang, F.N. Dai, D.F. Sun, Inorg. Chem. 55 (2016) 1782−1787. [36]S.R. Zhang, J. Li, D.Y. Du, J.S. Qin, S.L. Li, W.W. He, Z.M. Su, Y.Q. Lan, J. Mater. Chem. A 3 (2015) 23426–23434. [37]Divya Pratap Singh, Vinod P. Singh, Journal of Luminescence, 155, (2014) 7–14 [38]X. Zhang, R. Wang, G. Liu, C. Fan, S. Pu, Tetrahedron 72 (2016) 8449–8455. [39]S.M. Hossain, K. Singh, A. Lakma, R.N. Pradhan, A.K. Singh, Sensor Actuat B: Chem. 239 (2017) 1109−1117.

Fig. 1. a) Coordination environment of Yb atoms in UPC-22; b) The 1D wave-like SBU lines in UPC-22; c) 3D porous framework shown in the space-filling 13

mode along the [1 1 0] direction; d) a view of (4, 5, 8)-connected in topology

Fig. 2. Fluorescent spectra of 1 mg/mL UPC-22’ dispersed in EtOH treated with: a) TNP, and b) 4-NP; Stern-Volmer plots of: c) TNP, and d) 4-NP.

Fig. 3. The Corresponding Stern-Volmer plots of analytes.

14

Fig. 4. The PXRD patterns of UPC-22 treated in different solvents. Table 1. Crystal data and structure refinement parameters for UPC-22 Complex UPC-22 Empirical formula C49H27N6O30Yb4 Formula weight 1871.93 Temperature/K 107.43(10) Crystal system monoclinic Space group C2/c a/Å 22.5940(20) b/Å 14.3117 (11) c/Å 24.5365(2) α/° 90.00 β/° 99.59(9) γ/° 90.00 Volume/Å3 7823.19(11) ρcalcmg/mm3 1.589 −1 μ/mm 9.131 F(000) 3532.0 Reflections collected (°) 3.67-69.08° Independent reflections 24355 GOF 1.233 Final R indexes [all data] R1= 0.0530， wR2=0.1478 R1 = Σ| |Fo||Fc| |/ Σ|Fo|, wR2 = [Σw(Fo2Fc2]2]/ Σw(Fo2]2]1/2 1 2 +X, +Y ,+Z; -X, +Y, 1-Z; 31/2+X, 1/2+Y, +Z; 41/2-X, 1/2+Y, 1/2-Z; 5-X, -Y, -Z; 6+X, -Y, -1/2+Z; 71/2-X, 1/2-Y, -Z; 31/2+X, 1/2-Y, -1/2+Z

Highlights (i)

An ytterbium(III)-organic framework, UPC-22, was synthesized and 15

characterized. (ii)

The luminescent properties of UPC-22 were studied intensively.

(iii) UPC-22 exhibited fluorescent detection for nitroaromatics compounds and Al3+ ion. (iv) UPC-22 showed selective detection for 2, 4, 6-trinitrophenol in ethanol with a distinct red shift (57 nm).

16