Synthesis And Properties Of Copper Iodide Cluster Based On Rhodamine B

Copper（Ⅰ）-based clusters constitute is one large family of metal clusters.The widespread research on copper（Ⅰ）-based clusters is strongly motivated by relatively abundant element content,availability,low toxicity and low cost.Particular attention has been paid to the copper iodide clusters in light of abundant structures and unique luminescent behavior.In recent years,with the rapid development of science and technology,research on stimuli-responsive luminescent materials have gained considerable interest for the applications of smart photoactive materials in detection,labeling,sensing and optoelectronic display devices,and so on.The copper iodide clusters exhibit reversible thermochromism,mechanochromism and vapochromism in response to the stimuli effects of temperature,mechanical grinding and solvent vapor.Therefore,the copper iodide clusters display the great development prospects and potential application value in the research of multi-functional stimuli-responsive smart luminescent materials.However,most of them currently reported tune their fluorescence only in response to a single stimulus.More efforts are expected for seeking multi stimuli-responsive copper iodide cluster,It’s an effective strategy to design functional copper iodide clusters by the aid of periphery ligands and itselves’ photophysical properties.Spirocyclic derivatives of Rhodamine B display different photoactivity that caused by the ring-opening and ring-closing states under various conditions.Based on above al,in this article,Rhodamine B with N-ligand was synthesized and decorated as the peripheral of new copper iodide clusters,of which luminescent properties and simuli-responsive functions have been investigated in detail.The thesis includes two parts as follows:1.We devised a Rhodamine pyridine ligand L₁ with excel ent photophysical and photochemical properties.A cluster formula [Cu4I4（L₁）4]（1）with the corners of a closed and distorted [Cu4I4] cube was synthesized by a new precursor method.Its structure and properties have been characterized.The luminescent properties of the cluster 1 have been investigated in detail.Successfully,the cluster 1 showed a reversible tri-stimuli-responsive luminescence in response to external temperature,mechanical forces,and VOC vapors.Moreover,we firstly revealed its luminescence quenching properties by oxygen,which can be quenched by 82.2%.The aggregationinduced emission（AIE）phenomenon of cluster 1 was found also in acetonitrile-water system.When the H2 O content was increased to 80% and 90%,fluorescence intensity of 1 increased and the maximum emission was blue-shifted firstly and then red-shifted.2.A series of ligands L2,L3,L4 were synthesized by introducing push-pull electronic and conjugate planarity groups to decorate the pyridine ring of ligand L₁.Based on these ligands,multi-nuclearity clusters [Cu4I4（L2）4]（3）,[Cu3I3（L2）4]（4）,[Cu2I2（L3）2]·L3（5）were synthesized.These structures and properties have been characterized.Ligand L2 containing weak electron-donating group methyl was easy to assemble trinuclear clusters,while the ligand L3 contain electron-accepting group chlorine was likely to construct rhomboid dimer.It is of great significance in studing the synthesis of copper iodide clusters with modified ligands.