Solvent- and Temperature-Driven Photoluminescence Modulation in Porous Hofmann-Type Sr(II)-Re(V) Metal-Organic Frameworks
Solvent- and Temperature-Driven Photoluminescence Modulation in Porous Hofmann-Type Sr(II)-Re(V) Metal-Organic Frameworks
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多孔霍夫曼型 Sr(II)-Re(V) 金属有机框架中溶剂和温度驱动的光致发光调制
DOI：
10.1021/acs.inorgchem.1c00165
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发表时间：
2021
影响因子：
4.6
通讯作者：
Chorazy Szymon
中科院分区：
文献类型：
--
作者：
Liberka Michal;Zakrzewski Jakub J.;Heczko Michal;Reczynski Mateusz;Ohkoshi Shin-ichi;Chorazy Szymon
一个独特的三维(3D)发光骨架(MOF)家族，{[SrII(MeOH)5][ReV(CN)4(N)(bpen)0.5]·MeOH}n[1·MeOH；N3-=硝基配体，BPEN=1，2-双(4-吡啶)乙烷，和甲醇=甲醇]，{[SrII(MeOH)4][ReV(CN)4(N)(bpee)0.5]·2MeOH}n[2·MeOH；{[SrII(bpy)0.5(MeOH)2][ReV(CN)4(N)(bpy)0.5]}n(3·MeOH；=1，2-二(4-吡啶)乙烯]和BPY=4，4‘-联吡啶)。它们是通过Sr2+离子与四氰基硝基(V)金属配体[REV(CN)4(N)]2-和吡啶基有机间隔物(L=bPen，bpee，bpy)分子自组装而得到的。这种分子前体的组合导致了双金属的SrII-ReV氰基桥联的层，通过有机配体进一步键合成柱状的Hofmann型配位骨架。由于{REV-(L)-REV}部分的形成提供了金属到配体之间的发射电荷转移态，1·MeOH-3·MeOH表现出可被施加的有机配体从绿色调节到橙色的固态室温光致发光。最稳定的3·MeOHMOF基于交替的{Rev-(Bpy)-rev}和{SrII-(Bpy)-SrII}键，表现出三个可相互转化的、不同溶剂化的相，即甲醇溶解的3·MeOH、水合{[SrII(bpy)0.5(H2O)2][ReV(CN)4(N)(bpy)0.5]·0.6H2O}n(3·H2O)，和脱溶的{[SrII(Bpy)0.5][rev(CN)4(N)(Bpy)0.5]}n(3)。它们的形成与3·H2O对水和甲醇蒸汽的吸附特性有关。溶剂含量对发光的影响主要是通过在3·MeOH、3·H2O和3·H2O之间调节发射能量来实现的。所有的化合物都表现出温度驱动的发光调制，包括发射最大值和寿命的移动。热致变色发光响应对晶格中溶剂的存在和类型很敏感。这项工作表明，构建基于[REV(CN)4(N)]2的MOF是一条获得可通过外部刺激(如溶剂或温度)调节的先进固体发光体的有效途径。
A unique family of three-dimensional (3D) luminescent SrII–ReVmetal–organic frameworks (MOFs), {[SrII(MeOH)5][ReV(CN)4(N)(bpen)0.5]·MeOH}n[1·MeOH; N3–= nitrido ligand, bpen = 1,2-bis(4-pyridyl)ethane, and MeOH = methanol], {[SrII(MeOH)4][ReV(CN)4(N)(bpee)0.5]·2MeOH}n[2·MeOH; bpee = 1,2-bis(4-pyridyl)ethylene], and {[SrII(bpy)0.5(MeOH)2][ReV(CN)4(N)(bpy)0.5]}n(3·MeOH; bpy = 4,4′-bipyridine), is reported. They are obtained by the molecular self-assembly of Sr2+ions with tetracyanidonitridorhenate(V) metalloligands, [ReV(CN)4(N)]2–, and pyridine-based organic spacers (L = bpen, bpee, bpy). Such a combination of molecular precursors results in bimetallic SrII–ReVcyanido-bridged layers further bonded by organic ligands into pillared Hofmann-type coordination skeletons. Because of the formation of {ReV–(L)–ReV} moieties providing emissive metal-to-ligand charge-transfer states,1·MeOH–3·MeOHexhibit solid-state room-temperature photoluminescence tunable from green to orange by the applied organic ligand. The most stable MOF of3·MeOH, based on the alternating {ReV–(bpy)–ReV} and {SrII–(bpy)–SrII} linkages, exhibits three interconvertible, variously solvated phases, methanol-solvated3·MeOH, hydrated {[SrII(bpy)0.5(H2O)2][ReV(CN)4(N)(bpy)0.5]·0.6H2O}n(3·H2O), and desolvated {[SrII(bpy)0.5][ReV(CN)4(N)(bpy)0.5]}n(3). Their formation was correlated with water and methanol vapor sorption properties investigated for3·H2O. The solvent content affects the luminescence mainly by tuning the emission energy within the series of3·MeOH,3·H2O, and3. All of the obtained compounds exhibit temperature-driven modulation of luminescence, including the shift of the emission maximum and lifetime. The thermochromic luminescent response was found to be sensitive to the presence and type of solvent in the crystal lattice. This work shows that the construction of [ReV(CN)4(N)]2–-based MOFs is an efficient route toward advanced solid luminophores tunable by external stimuli such as solvent or temperature.