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1.
Xinwei Ye Joel E. Schmidt Ru‐Pan Wang Ilse K. van Ravenhorst Ramon Oord Tiehong Chen Frank de Groot Florian Meirer Bert M. Weckhuysen 《Angewandte Chemie (International ed. in English)》2020,59(36):15610-15617
To gain insight into the underlying mechanisms of catalyst durability for the selective catalytic reduction (SCR) of NOx with an ammonia reductant, we employed scanning transmission X‐ray microscopy (STXM) to study Cu‐exchanged zeolites with the CHA and MFI framework structures before and after simulated 135 000‐mile aging. X‐ray absorption near‐edge structure (XANES) measurements were performed at the Al K‐ and Cu L‐edges. The local environment of framework Al, the oxidation state of Cu, and geometric changes were analyzed, showing a multi‐factor‐induced catalytic deactivation. In Cu‐exchanged MFI, a transformation of CuII to CuI and CuxOy was observed. We also found a spatial correlation between extra‐framework Al and deactivated Cu species near the surface of the zeolite as well as a weak positive correlation between the amount of CuI and tri‐coordinated Al. By inspecting both Al and Cu in fresh and aged Cu‐exchanged zeolites, we conclude that the importance of the preservation of isolated CuII sites trumps that of Brønsted acid sites for NH3‐SCR activity. 相似文献
2.
Xinxin Wang Xu Ding Yucheng Jin Dongdong Qi Hailong Wang Yuesheng Han Tianyu Wang Jianzhuang Jiang 《Angewandte Chemie (International ed. in English)》2023,62(18):e202302808
Rational regulation of electronic structures and functionalities of framework materials still remains challenging. Herein, reaction of 4,4′,4′′-nitrilo-tribenzhydrazide with tris(μ2-4-carboxaldehyde-pyrazolato-N,N′)-tricopper (Cu3Py3) generates the crystalline copper organic framework USTB-11(Cu). Post-modification with divalent nickel ions affords the heterometallic framework USTB-11(Cu,Ni). Powder X-ray diffraction and theoretical simulations reveal their two-dimensional hexagonal structure geometry. A series of advanced spectroscopic techniques disclose the mixed CuI/CuII state nature of Cu3Py3 in USTB-11(Cu,Ni) with a uniform bistable Cu34+(CuI2CuII) : Cu35+(CuICuII2) (ca. 1 : 3) oxidation state, resulting in a significantly improved formation efficiency of the charge-separation state. This endows the Ni sites with enhanced activity and USTB-11(Cu,Ni) with outstanding photocatalytic CO2 to CO performance with a conversion rate of 22 130 μmol g−1 h−1 and selectivity of 98 %. 相似文献
3.
Dr. Charlène Esmieu Guillaume Ferrand Dr. Valentina Borghesani Dr. Christelle Hureau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1777-1786
In vitro Cu(Aβ1–x)-induced ROS production has been extensively studied. Conversely, the ability of N-truncated isoforms of Aβ to alter the Cu-induced ROS production has been overlooked, even though they are main constituents of amyloid plaques found in the human brain. N-Truncated peptides at the positions 4 and 11 (Aβ4–x and Aβ11–x) contain an amino-terminal copper and nickel (ATCUN) binding motif (H2N-Xxx-Zzz-His) that confer them different coordination sites and higher affinities for CuII compared to the Aβ1–x peptide. It has further been proposed that the role of Aβ4–x peptide is to quench CuII toxicity in the brain. However, the role of CuI coordination has not been investigated to date. In contrast to CuII, CuI coordination is expected to be the same for N-truncated and N-intact peptides. Herein, we report in-depth characterizations and ROS production studies of Cu (CuI and CuII) complexes of the Aβ4–16 and Aβ11–16 N-truncated peptides. Our findings show that the N-truncated peptides do produce ROS when CuI is present in the medium, albeit to a lesser extent than the unmodified counterpart. In addition, when used as competitor ligands (i.e., in the presence of Aβ1–16), the N-truncated peptides are not able to fully preclude Cu(Aβ1–16)-induced ROS production. 相似文献
4.
Christopher Paolucci Anuj A. Verma Shane A. Bates Vincent F. Kispersky Jeffrey T. Miller Rajamani Gounder W. Nicholas Delgass Fabio H. Ribeiro William F. Schneider 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(44):12022-12027
Operando X‐ray absorption experiments and density functional theory (DFT) calculations are reported that elucidate the role of copper redox chemistry in the selective catalytic reduction (SCR) of NO over Cu‐exchanged SSZ‐13. Catalysts prepared to contain only isolated, exchanged CuII ions evidence both CuII and CuI ions under standard SCR conditions at 473 K. Reactant cutoff experiments show that NO and NH3 together are necessary for CuII reduction to CuI. DFT calculations show that NO‐assisted NH3 dissociation is both energetically favorable and accounts for the observed CuII reduction. The calculations predict in situ generation of Brønsted sites proximal to CuI upon reduction, which we quantify in separate titration experiments. Both NO and O2 are necessary for oxidation of CuI to CuII, which DFT suggests to occur by a NO2 intermediate. Reaction of Cu‐bound NO2 with proximal NH4+ completes the catalytic cycle. N2 is produced in both reduction and oxidation half‐cycles. 相似文献
5.
Jerzy Podobiski Mariusz Gackowski Grzegorz Mordarski Katarzyna Samson Micha
liwa Dorota Rutkowska-Zbik Jerzy Datka 《Molecules (Basel, Switzerland)》2021,26(15)
The properties of both Cu2+ and Cu+ ions in zeolite CuY were followed with NO and CO as probe molecules. Cu2+ was found to be located in SII, SII*, and SIII sites, whereas Cu+ was found in SII and SII* sites. The fine analysis of the spectra of Cu2+-NO and Cu+-CO adducts suggests that both in SII and in SII* sites two kinds of Cu cations exist. They differ in the positive charge, which may be related to the varying numbers of AlO4− in close proximity. The experiments of NO and CO adsorption and desorption evidenced that both Cu2+ and Cu+ sites of highest positive charge bind probe molecules most strongly but activate them to a lesser extent than the Cu sites of lowest positive charge. The experiments of reduction with hydrogen evidenced that the Cu ions of higher positive charge are first reduced by hydrogen. On the other hand, Cu sites of the lowest positive charge are first oxidized by oxygen. The experiments with CuNaY zeolites of various Cu contents suggest that the first introduced Cu (at low Cu contents) created Cu+, which was the most neutralized by framework oxygens. Such Cu cations are the most stabilized by framework oxygens. 相似文献
6.
Kazuya Yamaguchi Dr. Takamichi Oishi Tatsuyori Katayama Noritaka Mizuno Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10464-10472
An easily prepared supported copper hydroxide on titanium oxide (Cu(OH)x/TiO2) showed high catalytic performance for the 1,3‐dipolar cycloaddition of organic azides to terminal alkynes in non‐polar solvents under anaerobic conditions. The reactions of various combinations of organic azides (four examples, including aromatic and aliphatic ones) and terminal alkynes (eleven examples, including aromatic, aliphatic, and double bond‐containing ones) exclusively proceeded to give the corresponding 1,4‐disubstituted‐1,2,3‐triazole derivatives in a completely regioselective manner. For the transformation of benzyl azide and ethynylbenzene with 0.12 mol % of Cu(OH)x/TiO2, the turnover frequency was 505 h?1 and the turnover number reached up to 800. These values were the highest among those with previously reported heterogeneous catalysts including Cu(OH)x/Al2O3. The observed catalysis was truly heterogeneous and the retrieved catalyst after the reaction could be reused at least three times with retention of its high catalytic performance. It was confirmed by the UV/Vis spectrum of Cu(OH)x/TiO2 and the amount of diyne formed that the CuII species in Cu(OH)x/TiO2 were reduced to CuI species by the alkyne–alkyne homocoupling at the initial stage of the reaction (during the pretreatment of Cu(OH)x/TiO2 with an alkyne). The catalytic reaction rate for the 1,3‐dipolar cycloaddition linearly increased with an increase in the amount of in situ generated CuI species. Therefore, the in situ generated CuI species would be the catalytically active species for the present 1,3‐dipolar cycloaddition. 相似文献
7.
Kazutaka Sonobe Dr. Makoto Tanabe Dr. Takane Imaoka Prof. Dr. Wang-Jae Chun Prof. Dr. Kimihisa Yamamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(33):8452-8456
Subnanoparticles (SNPs) with sizes of approximately 1 nm are attractive for enhancing the catalytic performance of transition metals and their oxides. Such SNPs are of particular interest as redox-active catalysts in selective oxidation reactions. However, the electronic states and oxophilicity of copper oxide SNPs are still a subject of debate in terms of their redox properties during oxidation reactions for hydrocarbons. In this work, in situ X-ray absorption fine structure (XAFS) measurements of Cu28Ox SNPs, which were prepared by using a dendritic phenylazomethine template, during temperature-programmed reduction (TPR) with H2 achieved lowering of the temperature (T50=138 °C) reported thus far for the CuII→CuI reduction reaction because of Cu−O bond elongation in the ultrasmall copper oxide particles. 相似文献
8.
Amy KaufmanKatz Liat Shimoni‐Livny Oshrit Navon Nadav Navon CharlesW. Bock JennyP. Glusker 《Helvetica chimica acta》2003,86(5):1320-1338
In this paper, we report the results of a study involving the coordination geometries of CuI, CuII, and CuIII crystal structures in the Cambridge Structural Database, and on Cu binding sites in proteins taken from the Protein Data Bank. The motifs used to bind two bridged Cu ions are also described. In addition, we report the results of ab initio molecular‐orbital calculations performed on a variety of model CuI/CuII complexes (CuI/CuII?XnYm (X, Y=NH3, SH2); n+m=4; n=0–4) to provide data on the structural and energetic changes that occur in isolated complexes when the oxidation state of the Cu ion is changed from II to I while the coordination number is conserved. The use of such simple ligands in these calculations eliminates constraints on the geometric changes that may be imposed by more‐complicated ligands. 相似文献
9.
G. N. Pirogova N. M. Panich R. I. Korosteleva Yu. V. Tyurkin Yu. V. Voronin 《Russian Chemical Bulletin》1994,43(10):1634-1636
The catalytic activity of MIMII
2O3 spinel-type complex oxides (MI = Cu, Ni, Mn, Zn, Mg, Co, MII = Co, Cr, Al) in the oxidation of CO and ethylbenzene has been investigated. The Co-containing catalysts were more active than the Cr- and Al-containing catalysts. The nature of the cation influenced the catalytic activity. Higher activities were observed for the catalysts containing two transition elements. A correlation between the catalytic and adsorption properties was established.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1730–1732, October, 1994. 相似文献
10.
Postsynthetic Metal and Ligand Exchange in MFU‐4l: A Screening Approach toward Functional Metal–Organic Frameworks Comprising Single‐Site Active Centers
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Dmytro Denysenko Dr. Jelena Jelic Prof. Dr. Karsten Reuter Prof. Dr. Dirk Volkmer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8188-8199
The isomorphous partial substitution of Zn2+ ions in the secondary building unit (SBU) of MFU‐4l leads to frameworks with the general formula [MxZn(5–x)Cl4(BTDD)3], in which x≈2, M=MnII, FeII, CoII, NiII, or CuII, and BTDD=bis(1,2,3‐triazolato‐[4,5‐b],[4′,5′‐i])dibenzo‐[1,4]‐dioxin. Subsequent exchange of chloride ligands by nitrite, nitrate, triflate, azide, isocyanate, formate, acetate, or fluoride leads to a variety of MFU‐4l derivatives, which have been characterized by using XRPD, EDX, IR, UV/Vis‐NIR, TGA, and gas sorption measurements. Several MFU‐4l derivatives show high catalytic activity in a liquid‐phase oxidation of ethylbenzene to acetophenone with air under mild conditions, among which Co‐ and Cu derivatives with chloride side‐ligands are the most active catalysts. Upon thermal treatment, several side‐ligands can be transformed selectively into reactive intermediates without destroying the framework. Thus, at 300 °C, CoII‐azide units in the SBU of Co‐MFU‐4l are converted into CoII‐isocyanate under continuous CO gas flow, involving the formation of a nitrene intermediate. The reaction of CuII‐fluoride units with H2 at 240 °C leads to CuI and proceeds through the heterolytic cleavage of the H2 molecule. 相似文献
11.
Two novel complexes of CuCN were characterized by using a single-crystal X-ray diffraction technique and Raman spectroscopy. In the structure of 2CuCN·DMSO ligand molecule demonstrates unique bridging mode, being bound to two CuI centers via oxygen and sulfur atoms. The bridging role of both CN groups and DMSO molecules results in the formation of (CuCN·DMSO)n framework. Along the channels of the network are running infinite zig-zag (CuCN)n chains, which are bound to the framework by elongated Cu…(CN) bonds. A mixed-valence [CuII(DMSO)6][CuI 6(CN)8] compound is composed of 3-D [CuI 6(CN)8]n anionic framework and located in the channels of partially disordered [CuII(DMSO)6]2+ cations. 相似文献
12.
《Journal of Coordination Chemistry》2012,65(17):3063-3071
A tetranuclear CuICuII mixed oxidation state complex, [CuII 2(μ-I)2CuI 2(μ-I)2(phenP)2I2] (phenPE: 2-(1H-pyrazol-1-yl)-1,10-phenanthroline), has been prepared and its crystal structure is determined by X-ray crystallography. In the complex, CuII is a distorted square pyramid and CuI is a distorted trigonal planar coordination environment; CuII and CuI are bridged by iodide. It is rare to form a CuII-iodide bond and for CuII and CuI to be bridged by iodide. In the crystal, there is a slipped π–π stacking between adjacent CuII complexes, which resulted in the formation of the 1-D chain along the c axis. The fitting for the variable-temperature magnetic susceptibility data gave magnetic coupling constant 2J?=??1.16?cm?1 and it may be ascribed to the intermolecular π–π magnetic coupling pathway. 相似文献
13.
The title compound, {[Cu(NH3)4][Cu(CN)3]2}n, features a CuI–CuII mixed‐valence CuCN framework based on {[Cu2(CN)3]−}n anionic layers and [Cu(NH3)4]2+ cations. The asymmetric unit contains two different CuI ions and one CuII ion which lies on a centre of inversion. Each CuI ion is coordinated to three cyanide ligands with a distorted trigonal–planar geometry, while the CuII ion is ligated by four ammine ligands, with a distorted square‐planar coordination geometry. The interlinkage between CuI ions and cyanide bridges produces a honeycomb‐like {[Cu2(CN)3]−}n anionic layer containing 18‐membered planar [Cu(CN)]6 metallocycles. A [Cu(NH3)4]2+ cation fills each metallocyclic cavity within pairs of exactly superimposed {[Cu2(CN)3]−}n anionic layers, but there are no cations between the layers of adjacent pairs, which are offset. Pairs of N—H...N hydrogen‐bonding interactions link the N—H groups of the ammine ligands to the N atoms of cyanide ligands. 相似文献
14.
Dr. Jabor Rabeah Dr. Valérie Briois Sven Adomeit Dr. Camille La Fontaine Dr. Ursula Bentrup Prof. Dr. Angelika Brückner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(33):7395-7404
Operando EPR, XANES/EXAFS, UV-Vis and ATR-IR spectroscopic methods have been coupled for the first time in the same experimental setup for investigation of unclear mechanistic aspects of selective aerobic oxidation of benzyl alcohol by a Cu/TEMPO catalytic system (TEMPO=2,2,6,6-tetramethylpiperidinyloxyl). By multivariate curve resolution with alternating least-squares fitting (MCR-ALS) of simultaneously recorded XAS and UV-Vis data sets, it was found that an initially formed (bpy)(NMI)CuI- complex (bpy=2,2′-bipyridine, NMI=N-methylimidazole ) is converted to two different CuII species, a mononuclear (bpy)(NMI)(CH3CN)CuII-OOH species detectable by EPR and ESI-MS, and an EPR-silent dinuclear (CH3CN)(bpy)(NMI)CuII(μ-OH)2 ⋅ CuII (bpy)(NMI) complex. The latter is cleaved in the further course of reaction into (bpy)(NMI)(HOO)CuII-TEMPO monomers that are also EPR-silent due to dipolar interaction with bound TEMPO. Both Cu monomers and the Cu dimer are catalytically active in the initial phase of the reaction, yet the dimer is definitely not a major active species nor a resting state since it is irreversibly cleaved in the course of the reaction while catalytic activity is maintained. Gradual formation of non-reducible CuII leads to slight deactivation at extended reaction times. 相似文献
15.
Cu/CuxS-Embedded N,S-Doped Porous Carbon Derived in Situ from a MOF Designed for Efficient Catalysis
Dongsheng Wang Mingyue Fan Tingyu He Prof. Fanming Zeng Dr. Xiaoli Hu Dr. Chun Li Prof. Zhongmin Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(44):11468-11476
The reasonable design of the precursor of a carbon-based nanocatalyst is an important pathway to improve catalytic performance. In this study, a simple solvothermal method was used to synthesize [Cu(TPT)(2,5-tdc)] ⋅ 2H2O (Cu-MOF), which contains N and S atoms, in one step. Further in-situ carbonization of the Cu-MOF as the precursor was used to synthesize Cu/CuxS-embedded N,S-doped porous carbon (Cu/CuxS/NSC) composites. The catalytic activities of the prepared Cu/CuxS/NSC were investigated through catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The results show that the designed Cu/CuxS/NSC has exceptional catalytic activity and recycling stability, with a reaction rate constant of 0.0256 s−1, and the conversion rate still exceeds 90 % after 15 cycles. Meanwhile, the efficient catalytic reduction of dyes (CR, MO, MB and RhB) confirmed its versatility. Finally, the active sites of the Cu/CuxS/NSC catalysts were analyzed, and a possible multicomponent synergistic catalytic mechanism was proposed. 相似文献
16.
W. -K. Dong Sh. -Sh. Gong Y. -X. Sun J. -F. Tong J. Yao 《Journal of Structural Chemistry》2011,52(5):1018-1024
Two new linear CuII complexes [Cu(L1)2] (I) (HL1 = (E)-3,5-dichloro-2-hydroxy benzaldehyde O-methyl oxime) and [Cu(L2)2] (II) (HL2 = (E)-3,5-dichloro-2-hydroxy benzaldehyde O-ethyl oxime) are synthesized and characterized by elemental analysis, IR, UV-Vis, and X-ray diffraction methods. X-ray crystallographic
analyses indicate that complexes I and II have a similar structure consisting of one CuII ion and two L− units. In the complexes, the CuII ion lying on an inversion centre is four-coordinated in a trans-CuN2O2 square planar geometry by two phenolate O and two oxime N atoms from two symmetry-related N,O-bidentate oxime-type ligands.
However, the crystal structure of the two complexes is different: complex I forms an infinite three-dimensional supramolecular network structure through intermolecular hydrogen bonding and π...π interaction,
while complex II forms an infinite one-dimensional supramolecular structure through intermolecular hydrogen bonds. 相似文献
17.
Ryo Sekiya Kazumasa Hosoya Shin‐ichi Nishikiori 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):i32-i34
The title compound, poly[diamminehexa‐μ‐cyano‐dicopper(I)copper(II)mercury(II)], [Cu3Hg(CN)6(NH3)2]n, has a novel threefold‐interpenetrating structure of three‐dimensional frameworks. This three‐dimensional framework consists of two‐dimensional network Cu3(CN)4(NH3)2 complexes and rod‐like Hg(CN)2 complexes. The two‐dimensional network complex contains trigonal–planar CuI (site symmetry m) and octahedral CuII (site symmetry 2/m) in a 2:1 ratio. Two types of cyanide group form bridges between three coordination sites of CuI and two equatorial sites of CuII to form a two‐dimensional structure with large hexagonal windows. One type of CN− group is disordered across a center of inversion, while the other resides on the mirror plane. Two NH3 molecules (site symmetry 2) are located in the hexagonal windows and coordinate to the remaining equatorial sites of CuII. Both N atoms of the rod‐like Hg(CN)2 group (Hg site symmetry 2/m and CN− site symmetry m) coordinate to the axial sites of CuII. This linkage completes the three‐dimensional framework and penetrates two hexagonal windows of two two‐dimensional network complexes to form the threefold‐interpenetrating structure. 相似文献
18.
Copper(II) and Sodium(I) Complexes based on 3,7‐Diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane‐5‐oxide: Synthesis,Characterization, and Catalytic Activity
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《化学:亚洲杂志》2018,13(19):2868-2880
The reaction of 3,7‐diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane (DAPTA) with metal salts of CuII or NaI/NiII under mild conditions led to the oxidized phosphane derivative 3,7‐diacetyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane‐5‐oxide (DAPTA=O) and to the first examples of metal complexes based on the DAPTA=O ligand, that is, [CuII(μ‐CH3COO)2(κO‐DAPTA=O)]2 ( 1 ) and [Na(1κOO′;2κO‐DAPTA=O)(MeOH)]2(BPh4)2 ( 2 ). The catalytic activity of 1 was tested in the Henry reaction and for the aerobic 2,2,6,6‐tetramethylpiperidin‐1‐oxyl (TEMPO)‐mediated oxidation of benzyl alcohol. Compound 1 was also evaluated as a model system for the catechol oxidase enzyme by using 3,5‐di‐tert‐butylcatechol as the substrate. The kinetic data fitted the Michaelis–Menten equation and enabled the obtainment of a rate constant for the catalytic reaction; this rate constant is among the highest obtained for this substrate with the use of dinuclear CuII complexes. DFT calculations discarded a bridging mode binding type of the substrate and suggested a mixed‐valence CuII/CuI complex intermediate, in which the spin electron density is mostly concentrated at one of the Cu atoms and at the organic ligand. 相似文献
19.
Dr. Yang Liu Dr. Stefan G. Resch Dr. Iris Klawitter Dr. George E. Cutsail III Dr. Serhiy Demeshko Dr. Sebastian Dechert Prof. Dr. Fritz E. Kühn Prof. Dr. Serena DeBeer Prof. Dr. Franc Meyer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(14):5745-5754
A neutral hybrid macrocycle with two trans-positioned N-heterocyclic carbenes (NHCs) and two pyridine donors hosts copper in three oxidation states (+I–+III) in a series of structurally characterized complexes ( 1 – 3 ). Redox interconversion of [LCu]+/2+/3+ is electrochemically (quasi)reversible and occurs at moderate potentials (E1/2=−0.45 V and +0.82 V (vs. Fc/Fc+)). A linear CNHC-Cu-CNHC arrangement and hemilability of the two pyridine donors allows the ligand to adapt to the different stereoelectronic and coordination requirements of CuI versus CuII/CuIII. Analytical methods such as NMR, UV/Vis, IR, electron paramagnetic resonance, and Cu Kβ high-energy-resolution fluorescence detection X-ray absorption spectroscopies, as well as DFT calculations, give insight into the geometric and electronic structures of the complexes. The XAS signatures of 1 – 3 are textbook examples for CuI, CuII, and CuIII species. Facile 2-electron interconversion combined with the exposure of two basic pyridine N sites in the reduced CuI form suggest that [LCu]+/2+/3+ may operate in catalysis via coupled 2 e−/2 H+ transfer. 相似文献
20.
Jia Meng Haonan Qin Dr. Haitao Lei Dr. Xialiang Li Juan Fan Prof. Dr. Wei Zhang Prof. Dr. Ulf-Peter Apfel Prof. Dr. Rui Cao 《Angewandte Chemie (International ed. in English)》2023,62(51):e202312255
In nature, cytochrome c oxidases catalyze the 4e− oxygen reduction reaction (ORR) at the heme/Cu site, in which CuI is used to assist O2 activation. Because of the thermodynamic barrier to generate CuI, synthetic Fe-porphyrin/Cu complexes usually show moderate electrocatalytic ORR activity. We herein report on a Co-corrole/Co complex 1-Co for energy-efficient electrocatalytic ORR. By hanging a CoII ion over Co corrole, 1-Co realizes electrocatalytic 4e− ORR with a half-wave potential of 0.89 V versus RHE, which is outstanding among corrole-based electrocatalysts. Notably, 1-Co outperforms Co corrole hanged with CuII or ZnII. We revealed that the hanging CoII ion can provide an electron to improve O2 binding thermodynamically and dynamically, a function represented by the biological CuI ion of the heme/Cu site. This work is significant to present a remarkable ORR electrocatalyst and to show the vital role of a second-sphere redox-active metal ion in promoting O2 binding and activation. 相似文献