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Metal porphyrin intercalated reduced graphene oxide nanocomposite utilized for electrocatalytic oxygen reduction 被引量:3
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作者 Mingyan Wang Qing Wang +7 位作者 Wei Zhu Ying Yang Huixian Zhou Fan Zhang Lihua Zhou Joselito M.Razal Gordon G.Wallace Jun Chen 《Green Energy & Environment》 SCIE 2017年第3期285-293,共9页
In this paper, we report a simple and facile self-assembly method to successfully fabricate cationic metal porphyrin-MtTMPyP(Mt= Cobalt(Ⅱ), Manganese(Ⅲ), or Iron(Ⅲ); TMPyP = 5, 10, 15, 20-tetrakis(N-methylpyridiniu... In this paper, we report a simple and facile self-assembly method to successfully fabricate cationic metal porphyrin-MtTMPyP(Mt= Cobalt(Ⅱ), Manganese(Ⅲ), or Iron(Ⅲ); TMPyP = 5, 10, 15, 20-tetrakis(N-methylpyridinium-4-yl) porphyrin) intercalated into the layer of graphene oxide(GO) by the cooperative effects of electrostatic and π-π stacking interaction between positively charged metal porphyrin and negatively charged GO sheets. Followed by reduction with hydrazine vapor, a series of novel 2 D MtTMPyP/rGO_n were fabricated. The as-prepared 2 D hybrids were fully characterized and tested as non-noble metal catalysts for oxygen reduction reaction(ORR) in an alkaline medium. The MtTMPyP/rGO_n hybrids, especially CoTMPyP/rGO_5, demonstrated an improved electrocatalytic activity for ORR and a number of exchanged electrons close to 4-electron reaction, increased stability and excellent tolerance to methanol, showing a potential alternative catalyst for ORR in fuel cells and air batteries. 展开更多
关键词 metal porphyrin Reduced graphene oxide INTERCALATION Oxygen reduction reaction Catalyst
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Synthesis of Novel Polymer-Bonded Water-Soluble Metal Porphyrins
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《Wuhan University Journal of Natural Sciences》 CAS 1999年第3期375-376,共2页
The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru3(CO)12], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a?2d respectively. Treatment of 2a... The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru3(CO)12], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a?2d respectively. Treatment of 2a?2d with Merrifield’s peptide resin obtained 3a?3d. The compounds 3a?3d reacted with methyl iodide respectively gave 4a?4d. New complexes 4a?4d have been identified by IR, UV-visible spectra, and AES. 展开更多
关键词 polymer bonded metal porphyrin water soluble porphyrin synthesis
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Synthesis of Polymer-Bonded Quaternary Ammonium Type Metal Porphyrins
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作者 Zao Ying LI Cong LI Xu Ye WU( Department of Chemistry, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期27-28,共2页
The reaction of pyrrole with 4-hydroxybenzaldehyde and 4-pyridinecarboxaldehyde afforded new porphyrin ligand 1. Treatment of 1 with copper( II ) acetate, cobalt ( II ) acetate gave complexes 2-3 respectively. 2 and 3... The reaction of pyrrole with 4-hydroxybenzaldehyde and 4-pyridinecarboxaldehyde afforded new porphyrin ligand 1. Treatment of 1 with copper( II ) acetate, cobalt ( II ) acetate gave complexes 2-3 respectively. 2 and 3 reacted with Merrifield's peptide resin produced 4 and 5. Complexes 4 and 5 reacted with methyl iodide respectively gave 6-7. The new compounds 1-7 have been identified by H-1 NMR, IR, MS and UV-visible spectra, elemental analysis and AES. 展开更多
关键词 polymer-bonded quaternary ammonium type metal porphyrin SYNTHESIS
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Synthesis of β-Cyclodextrin Bonded Metal Porphyrins
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作者 Zao Ying LI Cong LI +1 位作者 Xu Ye WU Yue Ning ZHANG (Department of Chemistry ,Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第6期493-494,共2页
6-Deoxy- 6-iodo-β-cyclodextrin (1) reacted with 5-(p-aminophenyl)-10, 15,20-triphenyl porphyrin(2), 5-(p-aminophenyl)-10,15,20-triphenyl nickel(Ⅱ) porphyrin [NiⅡTPPNH2P](3),5-(p-aminophenyl)-10,15,20-triphenyl mang... 6-Deoxy- 6-iodo-β-cyclodextrin (1) reacted with 5-(p-aminophenyl)-10, 15,20-triphenyl porphyrin(2), 5-(p-aminophenyl)-10,15,20-triphenyl nickel(Ⅱ) porphyrin [NiⅡTPPNH2P](3),5-(p-aminophenyl)-10,15,20-triphenyl manganese(Ⅲ) porphyrin [MnⅢTPPNH2P] (4) and 5-(p-aminophenyl)-10,l5,20-triphenyl carbonyl ruthenium porphyrin [RuⅡ (CO)TPPNH2P] (5) to generate the compounds 6-9, respectively. Those new compound 5-9 have been identified by 1H NMR, IR, MS and UV-visible spectra and elemental analysis. 展开更多
关键词 Β-CYCLODEXTRIN metal porphyrins SYNTHESIS
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Synthesis of Novel Polymer-Bonded Water-Soluble Metal Porphyrins
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期381-381,共1页
关键词 Synthesis of Novel Polymer-Bonded Water-Soluble metal porphyrins
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The Application of Novel Electrochemical Approach to Antioxidant Activity Assay of Metal Porphyrins with Bulky 3,5-Diisobornyl-4-hydroxyphenyl Moieties
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作者 Tatyana Rocheva Vladimir Tyurin +6 位作者 Dmitrii Belykh Аnna Moiseeva Jingwei Zhang Еvgeny Buravlev Irina Chukicheva Alexander Alexander Kutchin Elena Milaeva 《American Journal of Analytical Chemistry》 2014年第15期1028-1036,共9页
The complexes of biogenic metals (Zn2+,Cu2+,Co2+,Mn3+,Fe3+) based on meso-tetra(3,5-diisobor- nyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these com-pounds was studied using cyclic... The complexes of biogenic metals (Zn2+,Cu2+,Co2+,Mn3+,Fe3+) based on meso-tetra(3,5-diisobor- nyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these com-pounds was studied using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The antioxidant activity of complexes was estimated by means of the electrochemical assay based on the hydrogen atom transfer reaction to the stable radical 2,2’-diphenyl-1-picrylhydrazyl (DPPH). The RDE method was applied for this process monitoring. It was shown that the efficiency of the metal complexes (Cu2+,Co2+,Mn2+,Ni2+,Fe3+) is practically the same order as that of free base porphyrin 1. However the Zn2+ complex demonstrates significantly higher antioxidant activity, and the stoichiometry of the reaction was determined as σ = 4. The results demonstrate that porphyrin macrocycle can directly affect the antioxidant properties of 2,6-diisobornylphenol. 展开更多
关键词 metal porphyrinS Cyclic VOLTAMMETRY Rotating Disk Electrode 2 2’-Diphenyl-1-picrylhydrazyl ANTIOXIDANT Activity
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Synthesis and Characterization of β-Cyclodextrin Bonded Metal Porphyrins
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作者 李早英 李佳凤 李聪 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2002年第4期399-402,共4页
Reactions of 5-(p-aminophenyl)-10, 15, 20-triphenyl porphyrin (1) withRu_3(CO)_(12) or M(OCOCH_3)_2 (M= Ni, Mn) afforded metalloporphyrins (4―6), respectively.6-Deoxy-6-io-do-β-cyclodextrin (2) and mono (6-O-trifluo... Reactions of 5-(p-aminophenyl)-10, 15, 20-triphenyl porphyrin (1) withRu_3(CO)_(12) or M(OCOCH_3)_2 (M= Ni, Mn) afforded metalloporphyrins (4―6), respectively.6-Deoxy-6-io-do-β-cyclodextrin (2) and mono (6-O-trifluoromethanesulfonyl) pennethylatedβ-cyclodextrin (3) reacted with complexes 4―6 to give β-cyclodextrin bonded metal porphyrins(7―9) and permethylated β-cyclodextrin bonded me-tal porphyrins (10―12) respectively. These newcomplexes were identified by MS, IR, UV-visible and ~1H NMR spectra, and elemental analysis. 展开更多
关键词 β-cyclodextrin bonded metal porphyrins SYNTHESIS CHARACTERIZATION
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Occurrence and distribution of metals and porphyrins in Nigerian coal minerals 被引量:4
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作者 OLAJIRE A A AMEEN A B +1 位作者 ABDUL-HAMMED M ADEKOLA F A 《燃料化学学报》 EI CAS CSCD 北大核心 2007年第6期641-647,共7页
The metal contents of Nigerian coal minerals were analyzed using an atomic absorption spectrophotometer. Calcium, Na, and Fe occurred as the major elements with concentrations ranging from 9 782 μg/g for Ca to 432 μ... The metal contents of Nigerian coal minerals were analyzed using an atomic absorption spectrophotometer. Calcium, Na, and Fe occurred as the major elements with concentrations ranging from 9 782 μg/g for Ca to 432 μg/g for Na whereas K, Mg, Mn, Ni, Cr, Zn, Pb, and Cu, which occurred at trace levels ranged from 673.73 μg/g for Mg to 2.97 μg/g for Mn. The results of the quantitative analysis of porphyrins extracted from the coal minerals showed that Onyeama coal has the highest amount of porphyrins (ca~0.96 μg/g) while Okpara has the lowest (ca~0.30 μg/g). The porphyrins were qualitatively characterized by a combination of thin layer chromatography (TLC), infrared, and ultraviolet-visible spectrophotometers. The results of the mid infrared analysis (MIR) showed the presence of absorption bands at 3 440 cm~1~3 450 cm-1 and 1 640 cm-1~1 680 cm-1 , which are owing to the stretching vibrations of N ─ H and C─ C of aromatics, with C─ H out of plane (oop) bending vibrations at wavenumbers less than 900 cm-1, all of which are characteristic absorptions of porphyrin free base. The ultraviolet-visible data showed prominent peaks at ~400 nm(Soret band) and at wavelength ranges of 535 nm~550 nm(β-band) and 565 nm~ 600 nm (α-band) for the coal porphyrins analyzed. The geochemical significance of the metals and porphyrins in coal minerals are discussed. 展开更多
关键词 metalS porphyrinS COALS TLC ultraviolet-visible and infrared SPECTROPHOTOMETERS
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A Convenient Synthetic Method of Metal Dendritic Porphyrins 被引量:1
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作者 Wen Bin CUI Jie ZHOU +2 位作者 Lei CHEN Xiao Bin DENG Chun GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期999-1001,共3页
关键词 SYNTHESIS metal dendritic porphyrin.
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Distortions and Deformations of Metaled Meso-Substituted and Unsubstituted Porphyrins and Derivatives in Crystal Structures 被引量:1
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作者 Philippe V. Tsalu Tharcisse O. Monama +7 位作者 Hilaire V. Mambo Dorothée D. Tshilanda Pius T. Mpiana Bodrique M. Nsimba Virima Mudogo Pitchou N. Bokolombe Damien S. T. Tshibangu Zephyrin G. Yav 《Crystal Structure Theory and Applications》 2016年第1期1-15,共15页
Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were reviewed to show how far the meso-substitution by any functional group and the insertion of ... Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were reviewed to show how far the meso-substitution by any functional group and the insertion of metal in the porphyrins core macrocycle may affect the geometry. The analysis of twists and angles has shown two kinds of distortions: external [T(C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-X<sup>n</sup>) and T(C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-C<sup>α</sup>)] and internal [T(N<sup>m</sup>-C<sup>α</sup>-C<sup>meso</sup>-X<sup>n</sup>) and T(N<sup>n</sup>-C<sup>α</sup>-C<sup>meso</sup>-C<sup>α</sup>)] with averages of [+6&deg;and –6&deg;] and [–5&deg;and +5&deg;], respectively. In the meso-substituted case, the external and internal twists C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-X and N-C<sup>α</sup>-C<sup>meso</sup>-X, respectively are oppositely orientated. Similar effect is observed in meso-unsubstituted of C<sup>β</sup>-C<sup>α</sup>- C<sup>meso</sup>-H and N-C<sup>α</sup>-C<sup>meso</sup>-H. However, the external distortions are more significant than internal. Considering the same order, the limit of distortions is [97&deg;and 132&deg;(–48&deg;)] for external and [91&deg;(–89&deg;) and 52&deg;] for internal. In the two cases, the substituents have opposite directions of distortions. The meso-substituted porphyrins have a high limit of twisting than usubstituted one, depending of the weight of substituents. The average of the bond angular deformations is 168&deg;, almost planar. However, the limit of angular deformation is 94&deg;. 展开更多
关键词 metaled Meso-Substituted and Unsubstituted porphyrins and Derivates Crystals Structures Distortions and Bonds Angular Deformations
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Theoretical Investigations on Electronic Structures and Absorption Spectra of Unsymmetrical Metal-coordinated Neo-confused Porphyrin in Various Solvents 被引量:1
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作者 曹洪玉 郝娟媛 +3 位作者 司端惠 唐乾 郑学仿 郝策 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第8期1223-1232,共10页
Though the photo-physical properties of free base porphyrin are attractive, there are still problems for the materials with weak and narrow range absorption of visible light. The unsymmetrical neo-confused porphyrin d... Though the photo-physical properties of free base porphyrin are attractive, there are still problems for the materials with weak and narrow range absorption of visible light. The unsymmetrical neo-confused porphyrin derivatives were introduced as novel materials for the improvement of photo-chemical and photo-physical properties. The density function theory(DFT)and time dependent density function theory(TDDFT) were applied to calculate the absorption spectrum of unsymmetrical neo-confused porphyrin(N-CP) and metal-coordinated N-CP in various solutions. The Ni and Zn coordinated neo-confused porphyrin dipole moment values are smaller than the values of prototype porphyrin(Pro P) and N–CP. According to the electrophilicity index ω, Ni coordinated N–CP(Ni–N–CP) is susceptible to the polarity of solvents, while the Zn coordinated derivative(Zn–N–CP) is more immune to the solvent environment. Unlike the Gouterman's four frontier orbital model of common porphyrin materials, the electron transitions of N–CPs and metalcoordinated N–CPs from H–2 or lower molecular orbitals also contribute to ultraviolet and visible absorption. Most of oscillator strength f values of Zn–N–CP are significantly higher than the values of Ni–N–CP, which reflects the higher absorption intensity of Q and Soret bands. The maximum wavelength at 702.2 nm in vacuum drew our attention to the novel material. The broad absorption range, intense red-shifted Q band and higher stability in solvents suggest that N–CPs, especially Zn–N–CP, can be one class of new candidate dye-sensitized materials. 展开更多
关键词 metal-coordinated neo-confused porphyrin asymmetry C-N swapstrategy photo-physical property density function theory
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Synthesis and Liquid Crystal Properties of Transition Metal Complexes of Meso-tetra(4-n-myristyloxyphenyl)porphyrin 被引量:3
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作者 LIUWei SHIYu-hua SHITong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第1期20-23,共4页
Transition metal complexes of meso-tetra(4-myristyloxyphenyl)porphyrin TMPPM [M =Mn, Fe, Co, Ni, Cu, Zn; TMPP=mesotetra(4-myristyloxyphenyl)porphyrin] have been synthesized and characterized by means of elemental an... Transition metal complexes of meso-tetra(4-myristyloxyphenyl)porphyrin TMPPM [M =Mn, Fe, Co, Ni, Cu, Zn; TMPP=mesotetra(4-myristyloxyphenyl)porphyrin] have been synthesized and characterized by means of elemental analyses, UV-Vis spectra, infrared photoacoustic spectra, 1H NMR spectra, molar conductance and differential scanning calorimetry(DSC). The ligand and the Zn complex show liquid crystalline behavior. According to the DSC thermogram of the Zn complex, it exhibits a lower phase transition temperature -7.453 ℃ and a wide mesophase temperature span, 77 ℃. 展开更多
关键词 Transition metal complex meso-Tetra(4-n-myristyloxyphenyl)porphyrin Differential scanning calorimetry Liquid crystal
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5,10,15,20-Tetrakis(p-4-fluorobenzoyloxy)phenyl Porphyrin and Its Transition Metal Complexes
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作者 LIU Wei SHI Tong-shun LIU Guo-fa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第4期419-422,共4页
The properties of porphyrins can be changed through the choice of peripheral substituents and inserted metal ions. To obtain porphyrin complexes with novel structures, 5,10, 15,20-tetrakis(p-4-fluorobenzoyloxy) phen... The properties of porphyrins can be changed through the choice of peripheral substituents and inserted metal ions. To obtain porphyrin complexes with novel structures, 5,10, 15,20-tetrakis(p-4-fluorobenzoyloxy) phenyl perphyrin(TFBOPPH2 ) and its transition metal complexes {TFBOPPM [ M = Mn( Ⅲ ), Fe( Ⅲ ), Co( Ⅱ ), Ni( Ⅱ ), Cu( Ⅱ ) and Zn( Ⅱ ) ] } were synthesized and characterized by means of UV-Vis, IR photoacoustic speetrumetry, ^1H NMR, elemental analyses, molar conductance, and XPS methods. A structure is proposed, in which one porphyrln molecule is coordinated with a transition metal ion in a tetradentate fashion, while the chlorine ion is the balaneeable anion in Fe( Ⅲ ) and Mn( Ⅲ ) complexes. 展开更多
关键词 porphyrin SYNTHESIS Transition metal COMPLEX
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Novel Properties of Supramolecular Complexes Formed by Pairing Cationic Porphyrin and Anionic Metal-Oxo Cluster
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作者 Shu Qing LIU Ji Qing XU Hao Ran SUN Department of Chemistry, Jilin University, Changchun 130023 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期831-834,共4页
MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the ... MTBPyP (meso-tetrakis(4-N-benzylpyridyl)porphyrin, M=H-2, Zn) bearing positive charge has been shown to associate with SiW12O404- in water solution. The spectral evolution and Job's plots analyses reveal that the relatively stable aggregates contain equal numbers of MTBPyP4(+) and SiW12O404-. 展开更多
关键词 cationic porphyrin anionic metal-ore cluster ion pair supramolecular complex
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Comparing electrocatalytic hydrogen and oxygen evolution activities of first-row transition metal complexes with similar coordination environments 被引量:1
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作者 Xiaotong Jin Xialiang Li +6 位作者 Haitao Lei Kai Guo Bin Lv Hongbo Guo Dandan Chen Wei Zhang Rui Cao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期659-666,I0016,共9页
Developing cheap and efficient electrocatalysts for water splitting is required for energy conversion techniques.Many first-row transition metal complexes have been shown to be active for the hydrogen evolution reacti... Developing cheap and efficient electrocatalysts for water splitting is required for energy conversion techniques.Many first-row transition metal complexes have been shown to be active for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Metal ions play crucial roles in these catalytic processes,but the activity dependence on the nature of metal ions has been rarely studied due to the difficulty to compare metal complexes with different coordination environments.We herein reported the synthesis of a series of metal complexes of azido-substituted porphyrin(1),in which metal ions have very similar coordination environments.By grafting 1-M(M=Mn,Fe,Co,Ni,and Cu)onto alkynefunctionalized carbon nanotubes(CNTs)through the same covalent connection,the resulted hybrids 1-M@CNT were all active and robust for both electrocatalytic HER and OER in alkaline aqueous solutions.Among these hybrids,1-Fe@CNT displayed the highest electrocatalytic activity for HER,while 1-Co@CNT was the most active one for OER.Moreover,a two-electrode water electrolysis cell assembled with 1-Fe@CNT as the cathode and 1-Co@CNT as the anode required smaller applied bias potential by210 mV to get 10 mA/cm^(2)current density as compared to that assembled with Pt/C and Ir/C with the same amount of metal loading.This work is significant to correlate HER and OER activity with the nature of first-row transition metal ions and to highlight promising potential applications of molecular electrocatalysis in water splitting. 展开更多
关键词 metal porphyrins Molecular electrocatalysis Hydrogen evolution Oxygen evolution Water splitting
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Synthesis of Polymer-Bonded Carbonyl Ruthenium (Ⅱ) and Osmium (Ⅱ) Porphyrins 被引量:1
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作者 Zao Ying LI Cong LI +1 位作者 Jiang Lin LIANG Kun YAN(Department of Chemistry, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期77-78,共2页
The reactions of 5- (p-hydroxyphenyl)-10, 15, 20-tris (p-methoxyphenyl) porphyrin(H2Por) 1 respectively with triruthenium dodecacarbonyl [Ru3 (CO)12] and triosmiumdodecacarbonyl [Os3 (CO)12] under N2 gave complexes 2 ... The reactions of 5- (p-hydroxyphenyl)-10, 15, 20-tris (p-methoxyphenyl) porphyrin(H2Por) 1 respectively with triruthenium dodecacarbonyl [Ru3 (CO)12] and triosmiumdodecacarbonyl [Os3 (CO)12] under N2 gave complexes 2 and 3. Treatment of 2 (and 3) withMerrifield' peptide resin gave 4 (and 5) respectively. 展开更多
关键词 Polymer-bonded metal porphyrin synthesis
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基于卟啉金属有机框架的荧光探针检测有机磷农药残留
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作者 黄伦菁 李文静 +5 位作者 王政 张思雨 李徽 蒋闯 肖亚庆 刘英男 《食品安全质量检测学报》 CAS 2024年第6期93-100,共8页
目的建立基于卟啉金属有机框架的荧光探针检测有机磷农药(organophosphorus pesticide,OPs)残留的方法。方法以金属有机框架(PCN-224-Mn)的类氧化酶活性、硫代胆碱和邻苯二胺之间的竞争作用,以及OPs对乙酰胆碱酯酶的抑制作用为基础,采... 目的建立基于卟啉金属有机框架的荧光探针检测有机磷农药(organophosphorus pesticide,OPs)残留的方法。方法以金属有机框架(PCN-224-Mn)的类氧化酶活性、硫代胆碱和邻苯二胺之间的竞争作用,以及OPs对乙酰胆碱酯酶的抑制作用为基础,采用荧光法用于OPs残留的定量检测。结果以毒死蜱为模型,所构建的探针在0.05~50.00μg/mL的线性范围内对有机磷具有灵敏响应,检出限为29.6ng/mL。茶叶样品中毒死蜱残留的加标回收实验得到回收率为103.00%~112.00%,相对标准偏差小于3%。结论本研究不仅为精确、快速检测复杂样品中OPs残留提供了一种新的方法,而且为利用酶级联反应设计基于纳米酶的检测平台提供了新的见解。 展开更多
关键词 卟啉金属有机框架 类氧化酶活性 荧光检测 有机磷农药
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锆基卟啉金属有机框架的合成和性质研究
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作者 彭龙漩 张凤娟 +2 位作者 黄艳 陈楠 吕敏 《上海师范大学学报(自然科学版中英文)》 2024年第1期10-16,共7页
卟啉广泛存在于自然界,因其优异的光物理和电化学性能而备受关注.然而,卟啉的不稳定性、自猝灭和水溶性差等固有缺陷限制了它在生物学领域的应用.近年来,在金属有机框架(MOFs)中引入卟啉分子或利用卟啉作为有机连接剂构建卟啉金属有机框... 卟啉广泛存在于自然界,因其优异的光物理和电化学性能而备受关注.然而,卟啉的不稳定性、自猝灭和水溶性差等固有缺陷限制了它在生物学领域的应用.近年来,在金属有机框架(MOFs)中引入卟啉分子或利用卟啉作为有机连接剂构建卟啉金属有机框架(PMOFs)成为研究焦点.PMOFs既可以克服卟啉的局限性,又兼具卟啉与MOFs各自的独特性.文章通过改变反应条件,合成了3种不同形貌特征的锆基卟啉金属有机框架PCN-224,这种材料不仅保持了卟啉在红光照射下产生单线态氧(^(1)O_(2))的特点,还可作为药物载体,为PMOFs的结构调控和生物学应用提供了新思路. 展开更多
关键词 卟啉 金属有机框架(MOFs) 锆基卟啉金属有机框架 载药 单线态氧(^(1)O_(2))
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一例整合了三联吡啶钌和卟啉锌的金属-有机框架材料用于光催化二氧化碳还原全反应
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作者 陈慧滢 朱浩林 +1 位作者 廖培钦 陈小明 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第4期4-10,共7页
利用源源不断的太阳能,将CO_(2)和水转化为增值化学品,是缓解温室效应与能源危机的一种有前途的方法。由于催化体系中的不同功能性部分难以实现氧化与还原反应的耦合,使用水作为还原剂实现光催化CO_(2)还原是一项具有挑战性的工作。金... 利用源源不断的太阳能,将CO_(2)和水转化为增值化学品,是缓解温室效应与能源危机的一种有前途的方法。由于催化体系中的不同功能性部分难以实现氧化与还原反应的耦合,使用水作为还原剂实现光催化CO_(2)还原是一项具有挑战性的工作。金属有机框架(metal-organic framework,MOF)由于其较大的比表面积、多样化的活性位点和结构可调性,是CO_(2)光催化还原全反应的良好备选材料。本文中,我们首先整合了具有光活性的锌(Ⅱ)卟啉基元与联吡啶钌(Ⅱ)基元,构建了一种MOF光催化剂,记作PCN-224(Zn)-Bpy(Ru)。为了进行比较,还合成了两种仅具有锌(Ⅱ)卟啉或联吡啶钌(Ⅱ)基元的同构MOF,分别记作PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)。由测试结果可知,PCN-224(Zn)-Bpy(Ru)在乙腈和水混合溶液中表现出对CO_(2)还原可观的光催化活性(CO产率为7.6μmol·g^(-1)·h^(-1)),无需额外添加助催化剂、光敏剂或牺牲剂。通过质谱仪观测到^(13)CO(m/z=29)、^(13)C^(18)O(m/z=31)、^(16)O^(18)O(m/z=34)和^(18)O_(2)(m/z=36)信号,表明CO_(2)和H_(2)O分别作为CO和O_(2)的碳源和氧源,这进一步证实了光催化CO_(2)还原与H_(2)O氧化的耦合。然而,在相同条件下对PCN-224-Bpy(Ru)与PCN-224(Zn)-Bpy的光催化性能进行测试,CO产率分别仅为1.5与0μmol·g^(-1)·h^(-1)。机理研究表明,PCN-224(Zn)-Bpy(Ru)的最低未占据分子轨道(LUMO)电位比CO_(2)/CO的氧化还原电位更负,而最高占据分子轨道(HOMO)电位比H_(2)O/O_(2)的氧化还原电位更正,在热力学上满足了光催化CO_(2)还原全反应的要求。相比之下,不含联吡啶钌(Ⅱ)基元的PCN-224(Zn)-Bpy的HOMO电位更负于H_(2)O/O_(2)的氧化还原电位,这表明联吡啶钌(Ⅱ)基元在热力学上是光催化CO_(2)还原全反应所必需的。此外,光致发光光谱中,荧光几乎被PCN-224(Zn)-Bpy(Ru)猝灭,且平均光致发光寿命比PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)更长,这表明PCN-224中光生载流子的复合率较低。与PCN-224(Zn)-Bpy和PCN-224-Bpy(Ru)相比,PCN-224的光电流更高,这一现象也支持了中后者光生载流子的复合率较低这一结论。总而言之,在光催化CO_(2)还原过程中,锌卟啉(Ⅱ)配体既作为光敏单元,又作为CO_(2)还原活性位点,而联吡啶钌(Ⅱ)基元与锌(Ⅱ)卟啉基元的结合可以优化光催化剂的能带结构,进而促进光催化CO_(2)还原与H_(2)O氧化的耦合,从而实现了高效光催化CO_(2)还原全反应。 展开更多
关键词 金属有机框架 锌(Ⅱ)卟啉衍生物 联吡啶(Ⅱ)钌配合物 光生电荷 光催化CO_(2)还原
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第二配位层磺酸根在电催化析氢反应中的作用
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作者 王妮 张学鹏 +6 位作者 韩金秀 雷海涛 张清鑫 张航 张伟 Ulf-Peter Apfel 曹睿 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第2期88-94,共7页
析氢反应涉及电子和质子转移过程,即PCET过程,需要较大的过电势才可以驱动析氢反应发生.因此,合成过电势低,活性高的催化剂成为研究热点.自然界中,铁铁氢化酶可以将质子高效地还原成氢气.经研究,铁铁氢化酶的结构中有一个氨基基团位于... 析氢反应涉及电子和质子转移过程,即PCET过程,需要较大的过电势才可以驱动析氢反应发生.因此,合成过电势低,活性高的催化剂成为研究热点.自然界中,铁铁氢化酶可以将质子高效地还原成氢气.经研究,铁铁氢化酶的结构中有一个氨基基团位于活性金属中心铁的一侧,因此可以精准、有效地将质子传递给金属铁,从而提高催化效率.受自然界启发,很多分子催化剂模拟了自然界中氢化酶的结构,在分子内引入proton-relay基团,促进了析氢过程中PCET的过程.但目前只有关于这类分子催化剂通过促进质子传输进而提高催化效率的文献报道,尚未发现有关其改变氢氢成键方式的研究.前期工作中,本课题组设计合成了卟啉镓并用于电催化质子还原的研究.利用循环伏安法对其析氢活性进行了测试,发现分别以三氟乙酸(TFA)和醋酸(HOAc)作为质子源时,催化析氢的电化学行为不同.在强酸(TFA)体系中,催化剂在经历了两电子还原后,生成的金属氢化物可以直接和质子发生反应,生成氢气.但是在弱酸(HOAc)体系中,生成的金属氢化物需要再经过一电子的还原才可以驱动整个催化反应的进行.在该工作的基础上,通过调研文献得知,在分子内引入酸基团时,可以极大地增加中心金属周围的质子浓度,并且改善质子传输的速率.基于以上想法,在卟啉镓的分子内引入了磺酸基团作为proton-relay的中心,使催化剂能够在弱酸存在的体系中实现强酸的催化析氢路径.本文合成了第二配位层带磺酸基团的卟啉镓化合物(1).在弱酸(HOAc)作为外加质子源时,利用循环伏安法证明了生成的镓氢化合物是真正的活性物种,可以驱动整个催化析氢反应的发生.循环伏安法实验结果表明,化合物1具有很高的催化活性,其TOF值可以达到1.3×10^(5)s^(-1).为了进一步研究催化机理,通过停留光谱实验对该反应进行了原位监测,将化合物1两电子还原后形成的物种(12-)与HOAc的乙腈溶液混合,混合液的紫外光谱可以迅速变回到化合物1原始的光谱,进一步证明了引入磺酸基团可以使生成的镓氢化合物能够直接与弱酸(HOAc)发生反应生成氢气.理论计算结果表明,引入磺酸基团可以显著地降低氢氢成键的能垒.因此,引入磺酸基团,利用限域效应使催化剂周围的质子浓度和强度增强,从而使催化剂能够在弱酸体系中通过强酸的催化路径生成氢气.综上,本文阐明了第二配位层proton-relay基团具有促进质子转移和调控氢氢成键过程的作用,为设计具有优异电催化析氢性能的分子催化剂提供了新的思路. 展开更多
关键词 分子电催化 金属氢化物 析氢反应 镓氢化合物 第二配位层 氢氢成键
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