Two Cadmium Germanophosphates [CdGe(μ₂ -O)(HPO₄ )₂ - (H₂ O)₂ ]^. H₂ O and Anhydrous Cd₇ Ge(PO₄ )₆ : Syntheses, Crystal Structures and Photoluminescence Properties

Abstract

Two cadmium germanophosphates (GePOs), namely, [CdGe(μ2‐O)(HPO4)2(H2O)2].H2O (1) and anhydrous Cd7Ge(PO4)6 (2) have been prepared by hydro/solvothermal method. Compound 1 crystallizes in a centrosymmetric (CS) space group P‐1 with a 2D layer structure, which is composed of 1D [Cd(HPO4)4(H2O)2]∞ and [Ge(μ2‐O)2(HPO4)4]∞ infinite chains. Compound 2 crystallizes in a centrosymmetric space group R‐3 with a complicated 3D network, which is built from CdO6 octahedra, GeO6 octahedra and PO4 tetrahedra. TGA results showed that the structure of anhydrous Cd7Ge(PO4)6 was stable under 800 °C. The luminescent properties of two compounds were also investigated at room temperature. The color coordinate of 2 (0.2613, 0.2649) is close to that of the balanced white‐light emission (0.333, 0.333), which indicates that compound 2 is a good blue light emitted material at room temperature under UV irradiation exaction, thus anhydrous compound 2 might be a potential candidate for blue light‐emitted material.

Robustness, Selective Gas Separation, and Nitrobenzene Sensing on Two Isomers of Cadmium Metal–Organic Frameworks Containing Various Metal–O–Metal Chains

“…The photoluminescence spectrum of the free ligand H 3 PTB exhibits maximum peaks at 516 nm at excitation of 350 nm, which may originate from the ligand-centered electronic π···π* transition. , FJU-35 and FJU-36 display similar fluorescence emission spectra upon excitation at 350 nm with a strong emission peak and a weak emission shoulder peak at 396 and 557 nm, respectively. The strong emission peak could be assigned to metal chain centered emission, which originates from the Cd II –O–Cd II charge transfer (O → Cd II ) excited state . The weak shoulder peak at 557 nm can be attributed to the ligand-centered π → π* and or n → π* transition with a red shift (41 nm) with respect to free H 3 PTB, and the weaker emission on FJU-35 may be caused by more sensitive Cd II –O–Cd II chains. , …”

“…The strong emission peak could be assigned to metal chain centered emission, which originates from the Cd II −O−Cd II charge transfer (O → Cd II ) excited state. 63 The weak shoulder peak at 557 nm can be attributed to the ligand-centered π → π* and or n → π* transition with a red shift (41 nm) with respect to free H 3 PTB, and the weaker emission on FJU-35 may be caused by more sensitive Cd II −O−Cd II chains. 64,65 Such interesting fluorescent features stimulate us to further explore their photoluminescent properties in different solvents, such as, N,N-dimethylformamide (DMF), acetonitrile, dichloromethane, 1,4-dioxane, methanol (CH 3 OH), ether, acetone, N, N-dimethylacetamide (DMA), ethyl acetate (EAC), chloroform (CHCl 3 ), and nitrobenzene (NB).…”

Syntheses, Crystal Structures and Luminescent Properties of Two New Heterometallic Phosphates: Sn2Ge(PO4)2(OH)2 and Sn2Mn(PO4)2

“…Compound 1 and 2 were obtained under the similar condition except that triethylamine and 1,2‐propanediol were added into the reaction system of anhydrous 2 . Prior to this work, we also prepared another anhydrous metal phosphates:Cd 7 Ge(PO 4 ) 6 , by using triethylamine and 1,2‐propanediol as mixed solvents under mild conditions, indicating that the presence of the mixed solvents can effectively prevent hydroxyl groups and water molecules from entering the reaction system, which is beneficial to obtain anhydrous materials . It should be noted that single‐crystals of 2 could not be obtained in the absence of GeO 2 , which may act as a mineralizer.…”

“…Recently, we have also successfully prepared two bimetallic phosphates, namely, [CdGe(μ 2 ‐O)(HPO 4 ) 2 (H 2 O) 2 ] . H 2 O ( 1 ) and anhydrous Cd 7 Ge(PO 4 ) 6 ( 2 ) by a hydro/solvothermal method, and the anhydrous Cd 7 Ge(PO 4 ) 6 shows high thermal stability with a blue emission . This proves a good strategy to discover new metal‐phosphates under mild conditions, especially for the anhydrous metal phosphonates.…”