N-K2Ti4O9/UiO-66-NH2 composites synthesized by a facile solvothermal method have a core-shell structure with UiO-66-NH2 forming the shell around a N-K2Ti4O9 core.Their photocatalytic activities in the degradation of d...N-K2Ti4O9/UiO-66-NH2 composites synthesized by a facile solvothermal method have a core-shell structure with UiO-66-NH2 forming the shell around a N-K2Ti4O9 core.Their photocatalytic activities in the degradation of dyes under visible light irradiation were investigated.The N-K2Ti4O9/UiO-66-NH2 composites exhibited higher photocatalytic activity than the pure components.This synergistic effect was due to the high adsorption capacity of UiO-66-NH2 and that the two components together induced an enhanced separation efficiency of photogenerated electron-hole pairs.The mass ratio of N-K2Ti4O9 to ZrCl4 of 3：7 in the composite exhibited the highest photocatalytic activity.Due to the electrostatic attraction between the negatively charged backbone of UiO-66-NH2with the positively charged groups of cationic dyes,the composites were more photocatalytically active for cationic dyes than for anionic dyes.展开更多
separation is an attractive alternative to filtration or centrifugation for separating solid catalysts from a liquid phase, Here, core-shell Fe3O4@UiO-66-NH2 nanohybrids with well-defined structures were constructed b...separation is an attractive alternative to filtration or centrifugation for separating solid catalysts from a liquid phase, Here, core-shell Fe3O4@UiO-66-NH2 nanohybrids with well-defined structures were constructed by dispersing magnets in a dimethylformamide （DMF） solution con- taining two metal-organic framework （MOF） precursors, namely ZrCI4 and 2-aminobenzenetricar- boxylic acid. This method is simpler and more efficient than previously reported step-by-step method in which magnets were consecutively dispersed in DMF solutions each containing one MOF precursor, and the obtained Fe304@UiO-66-NH2 with three assembly cycles has a higher degree of crystallinity and porosiW. The core-shell Fe3O4@UiO-66-NH2 is highly active and selective in Knoevenagel condensations because of the bifunctionality of UiO-66-NH2 and better mass transfer in the nano-sized shells. It also has good recycling stability, and can be recovered magnetically and reused at least four times without significant loss of catalytic activity and framework integrity. The effects of substitution on the reactivity of benzaldehyde and of substrate size were also investigated.展开更多
In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)...In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)and Methyl Orange(MO)) and the cationic dyes(Neutral Red(NR), Fuchsin Basic(FB), Methylene Blue(MB),and Safranine T(ST)) has been evaluated. The results clearly reveal a significant selectivity towards anionic dyes. Such an observation agrees with a plethora of reports of UiO-66 superior affinity towards other anionic species(Floride, PO_4^(3-), Diclofenac sodium, Methylchlorophenoxy-propionic acid, Phenols, CrO_4^(2-), SeO_3^(2-), and AsO_4^-). The adsorption process of ARS as an example has been optimized using the central composite design(CCD). The resultant statistical model indicates a crucial effect of both pH and sorbent mass. The optimum conditions were determined to be initial dye concentration 11.82 mg.L^(-1), adsorbent amount 0.0248 g, shaking time of 36 min and pH 2. The adsorption process proceeds via pseudo-second order kinetics(R^2= 0.999). The equilibrium data were fit to Langmuir and Tempkin models(R^2= 0.999 and 0.997 respectively). The results reveal an exceptional removal for the anionic dye(Alizarin Red S.) with a record adsorption capacity of400 mg·g^(-1). The significantly high adsorption capacity of UiO-66 towards ARS adds further evidence to the recently reported exceptional performance of MOFs in pollutants removal from water.展开更多
In this study,a novel copper ion(Cu^(2+))crosslinked composites beads with components of sodium alginate(SA)as gel matrix and UiO-66-(COOH)_(2) metal organic framework(MOF)nanoparticle as functional fller could efecti...In this study,a novel copper ion(Cu^(2+))crosslinked composites beads with components of sodium alginate(SA)as gel matrix and UiO-66-(COOH)_(2) metal organic framework(MOF)nanoparticle as functional fller could efectively adsorb toxins in dialysate.The maximum adsorption capacity of the optimized composite beads(Cu-SA/U-4)for creatinine reached 125.0 mg/g with a positive synergistic efect based on Langmuir isotherm model and pseudo-second-order kinetic model,which was 1.75 times and 1.50 times that of single component beads(Cu-SA)and UiO-66-(COOH)_(2) nanoparticle respectively.Furthermore,when the dialysis performance using thin-flm nanofbrous composite(TFNC)membrane was comparable,introduction of Cu-SA/U-4 beads into the dialysate allowed the volume of dialysate reduced to one-tenth of that without beads.Therefore,the coordination of such highly efcient adsorbent beads and TFNC dialysis membrane can economize the usage of the dialysate and contributes to realize lightweight hemodialysis.More importantly,we not only prepared a kind of composite bead via carefully designed strategy,but also proposed widely applicable idea of using adsorbents in combination with dialysis membrane to realize lightweight or miniaturized hemodialysis.展开更多
基金supported by the National Natural Science Foundation of China (51372062)the Anhui Provincial Natural Science Foundation(1508085MB28,1308085MB21)~~
文摘N-K2Ti4O9/UiO-66-NH2 composites synthesized by a facile solvothermal method have a core-shell structure with UiO-66-NH2 forming the shell around a N-K2Ti4O9 core.Their photocatalytic activities in the degradation of dyes under visible light irradiation were investigated.The N-K2Ti4O9/UiO-66-NH2 composites exhibited higher photocatalytic activity than the pure components.This synergistic effect was due to the high adsorption capacity of UiO-66-NH2 and that the two components together induced an enhanced separation efficiency of photogenerated electron-hole pairs.The mass ratio of N-K2Ti4O9 to ZrCl4 of 3：7 in the composite exhibited the highest photocatalytic activity.Due to the electrostatic attraction between the negatively charged backbone of UiO-66-NH2with the positively charged groups of cationic dyes,the composites were more photocatalytically active for cationic dyes than for anionic dyes.
基金supported by the National Natural Science Foundation of China (21203017)Open Fund of State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (N-11-3)+1 种基金Program for Liaoning Excellent Talents in University (LNET)the Funda-mental Research Funds for the Central Universities (DC201502020304)~~
文摘separation is an attractive alternative to filtration or centrifugation for separating solid catalysts from a liquid phase, Here, core-shell Fe3O4@UiO-66-NH2 nanohybrids with well-defined structures were constructed by dispersing magnets in a dimethylformamide （DMF） solution con- taining two metal-organic framework （MOF） precursors, namely ZrCI4 and 2-aminobenzenetricar- boxylic acid. This method is simpler and more efficient than previously reported step-by-step method in which magnets were consecutively dispersed in DMF solutions each containing one MOF precursor, and the obtained Fe304@UiO-66-NH2 with three assembly cycles has a higher degree of crystallinity and porosiW. The core-shell Fe3O4@UiO-66-NH2 is highly active and selective in Knoevenagel condensations because of the bifunctionality of UiO-66-NH2 and better mass transfer in the nano-sized shells. It also has good recycling stability, and can be recovered magnetically and reused at least four times without significant loss of catalytic activity and framework integrity. The effects of substitution on the reactivity of benzaldehyde and of substrate size were also investigated.
文摘In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)and Methyl Orange(MO)) and the cationic dyes(Neutral Red(NR), Fuchsin Basic(FB), Methylene Blue(MB),and Safranine T(ST)) has been evaluated. The results clearly reveal a significant selectivity towards anionic dyes. Such an observation agrees with a plethora of reports of UiO-66 superior affinity towards other anionic species(Floride, PO_4^(3-), Diclofenac sodium, Methylchlorophenoxy-propionic acid, Phenols, CrO_4^(2-), SeO_3^(2-), and AsO_4^-). The adsorption process of ARS as an example has been optimized using the central composite design(CCD). The resultant statistical model indicates a crucial effect of both pH and sorbent mass. The optimum conditions were determined to be initial dye concentration 11.82 mg.L^(-1), adsorbent amount 0.0248 g, shaking time of 36 min and pH 2. The adsorption process proceeds via pseudo-second order kinetics(R^2= 0.999). The equilibrium data were fit to Langmuir and Tempkin models(R^2= 0.999 and 0.997 respectively). The results reveal an exceptional removal for the anionic dye(Alizarin Red S.) with a record adsorption capacity of400 mg·g^(-1). The significantly high adsorption capacity of UiO-66 towards ARS adds further evidence to the recently reported exceptional performance of MOFs in pollutants removal from water.
基金This work was supported by the Fundamental Research Funds for the Central Universities(2232020A-04)Shanghai Municipal Natural Science Foundation(19ZR1401300).
文摘In this study,a novel copper ion(Cu^(2+))crosslinked composites beads with components of sodium alginate(SA)as gel matrix and UiO-66-(COOH)_(2) metal organic framework(MOF)nanoparticle as functional fller could efectively adsorb toxins in dialysate.The maximum adsorption capacity of the optimized composite beads(Cu-SA/U-4)for creatinine reached 125.0 mg/g with a positive synergistic efect based on Langmuir isotherm model and pseudo-second-order kinetic model,which was 1.75 times and 1.50 times that of single component beads(Cu-SA)and UiO-66-(COOH)_(2) nanoparticle respectively.Furthermore,when the dialysis performance using thin-flm nanofbrous composite(TFNC)membrane was comparable,introduction of Cu-SA/U-4 beads into the dialysate allowed the volume of dialysate reduced to one-tenth of that without beads.Therefore,the coordination of such highly efcient adsorbent beads and TFNC dialysis membrane can economize the usage of the dialysate and contributes to realize lightweight hemodialysis.More importantly,we not only prepared a kind of composite bead via carefully designed strategy,but also proposed widely applicable idea of using adsorbents in combination with dialysis membrane to realize lightweight or miniaturized hemodialysis.
