Syntheses And Properties Of Cd Boron Imidazolate Frameworks

Metal-organic frameworks(MOFs)have triggered extensive attention mainly own to their interesting structures and potential applications in catalysis,luminescence,gas storage and separation.Boron imidazolate frameworks(BIFs),as a special class of MOFs,can synthesize directly four-connected B(im)4-and three-connected BH(im)3-ligands,which can control the connection mode of boron imidazole ligands.The aim of this dissertation is to construct a series of open functional BIFs materials by the targeted assembly of Cd2+ aromatic carboxylate and pre-synthesized boron imidazolate ligands.Meanwhile,structure and performance of the BIFs were investigated.Main results are summarized briefly as follows:(1)The construction of neutral Cd-BIFs based aromatic dicarboxylate.Six 3D neutral BIFs have been synthesized by adopting aromatic dicarboxylate with different substituted group and pre-synthesized KB(im)4 ligands under the condition of solvothermal treatment,including zeolite-like ABW-BIF-42 and BCT-BIF-75,BIF-76 and BIF-80 with fsx and tcs topologies,BIF-77 and BIF-78 with hep topology.Amine-functionalized BIF-77 can directly load Ag NPs without the presence of other reducing agents for photocatalytic degradation of methyleneblue(MB).Hydroxy-functional BIF-80 shows an obvious blue shift about 36 nm of luminescence after loading Ag nanoparticles(Ag NPs).These results enrich the kinds of BIFs,and provide a new method towards the construction of neutral BIFs.(2)The construction of anionic Cd-BIFs based aromatic tricarboxylate.Anionic BIF-81 and BIF-82 have been synthesized by the targeted assembly of BTC(1,3,5-Benzenetricarboxylic acid)and KB(im)4 ligands by the hydrothermal method,showing reversible structural transformation under certain temperature.BIF-81 with blue emission can tune the white-light emission via doping mixed Li3+,with an appropriate ratio(Ln = Eu and Tb).Meanwhile BIF-82 can interfuse Ag+,and then produced Ag NPs into its structure for further sensing of cysteine.This work opens a new route for building anionic BIFs,and also shows the potential applications in the field of biological.(3)The construction of 2D ultra-thin Cd-BIFs.Two 2D layer structures(BIF-73/74)were successfully obtained by adopting DHT(2,5-Dihydroxyterephthalic acid)and KBH(im)3 ligands under the condition of solvothermal treatment.Due to the existence of hydroxyl groups in the structures,BIF-73 was selected as a representative and the detection of Fe3+ was studied.And the 2D ultra-thin Cd-BIFs were produced by liquid exfoliation method,which can effectively promote the detection of Fe3+.