Turnover Frequency Value Research Articles

Kinetics of simultaneous hydrodesulfurization and hydrodenitrogenation reactions using CoMoP/Al2O3 and NiMoP/Al2O3

Hydrodesulfurization (HDS) is a key reaction to achieve diesel production at the specified low sulfur levels and is highly affected by a competing reaction involving nitrogen removal through hydrodenitrogenation (HDN). This work evaluated kinetic parameters of simultaneous reactions of HDS of dibenzothiophene (DBT) and HDN of quinoline (Q) using CoMoP/Al2O3 and NiMoP/Al2O3 catalysts under operational conditions that allow a wide range of reagent conversions. Estimated parameters were evaluated using rigorous statistical analysis. Good fits for the evaluated experimental data were provided by both power-law and Langmuir-Hinshelwood models. Turnover frequency values highlight adsorption and competition effects between nitrogen-containing compounds and sulfur-containing compounds. NiMoP catalyst showed higher hydrogenating power than CoMoP, with larger absolute value of the estimated adsorption enthalpy (−120 kJ.mol−1 for NiMoP and −75 kJ.mol−1 for CoMoP), suggesting strong adsorption of nitrogen compounds. A catalyst with more hydrogenating power is also more capable of performing both HDN and HDS reactions simultaneously.

Engineering pKa value of 3° amine for enhanced production of dialkyl carbonate via Se-catalyzed oxidative carbonylation

C1 chemistry plays a vital role in the chemical and energy industry in terms of recycling C1 molecules and high productivity. As one of the C1 chemistry reactions, oxidative carbonylation of alcohols to corresponding dialkyl carbonates (DACs) has been studied but still has problems with catalysts in terms of corrosion and low yield of DACs. To address this issue, various Se/Ph2Se2/tertiary amine catalytic systems were applied to the oxidative carbonylation of alcohols to produce DACs, and Se/Ph2Se2/DMAP showed higher catalytic activity [60.9% yield of bis(2-methoxyethyl) carbonate (BMEC) at a turnover frequency (TOF) value = 32.5 h−1] compared to other tertiary amines (TAs) systems in the oxidative carbonylation of 2-methoxyethanol (MEG). Moreover, with this catalytic system, the oxidative carbonylation of C1–C4 n-alcohols yielded over 40% of DACs with high TOF value (over 40 h−1), which are unprecedented catalytic activity in terms of both yield and TOF value, compared with previous reports. We also found a relationship between the hydrogen bond (HB) strength of alcohol···TA and the catalytic performances. Additionally, the catalytic activity with pKa of TA showed volcano-type correlation. Finally, we investigated the role of TA and proposed a plausible mechanism based on 1H NMR study and the aforementioned correlations.

Effectiveness of the 3D-printing procedure in the synthesis of hybrid catalysts for the direct hydrogenation of CO2 into dimethyl ether

This work highlights the effectiveness of an unconventional synthesis of hybrid systems for the direct hydrogenation of carbon dioxide into dimethyl ether (DME), based on micro-extrusion of a ink-like catalytic paste by a robocasting procedure. Due to the possibility to exert a fine control over the structure, surface and geometric architecture, the adopted printing technique really ensures a superior management of heat and mass constraints in respect of the conventional powdered catalysts, the catalyst functionality resulting to be tightly dependent on the cooperation between metal-oxide and acidic phase. Additionally, the accessibility both of the CO2 activation and methanol (MeOH) dehydration sites over the hybrid micro-extruded catalyst most importantly affects the catalytic performance, as suggested by the values of turnover frequency of CO2 conversion and DME formation pointing out the need for a favorable exposure of chemisorption sites of different nature to enhance the specific reactivity.

A step‐growth strategy to grow vertical porous aromatic framework nanosheets on graphene oxide: Hybrid material‐confined Co for ammonia borane methanolysis

AbstractThe rational synthesis of a two‐dimensional (2D) porous aromatic framework (PAF) with a controllable growth direction remains a challenge to overcome the limitation of traditional stacked 2D materials. Herein, a step‐growth strategy is developed to fabricate a vertically oriented nitrogen‐rich porous aromatic framework on graphene oxide (V‐PAF‐GO) using monolayer benzidine‐functionalized GO (BZ‐GO) as a molecular pillar. Then, the confined Co nanoparticle (NP) catalysts are synthesized by encapsulating ultra‐small Co into the slit pores of V‐PAF‐GO. Due to the high nitrogen content, large specific surface area, and adequate slit pores, the optimized vertical nanocomposites V‐PAF‐GO provide abundant anchoring sites for metal NPs, leading to ultrafine Co NPs (1.4 nm). The resultant Co/V‐PAF‐GO catalyst shows an extraordinary catalytic activity for ammonia borane (AB) methanolysis, yielding a turnover frequency value of 47.6 min−1 at 25°C, comparable to the most effective non‐noble‐metal catalysts ever reported for AB methanolysis. Experimental and density functional theory studies demonstrate that the electron‐donating effect of N species of PAF positively corresponds to the low barrier in methanol molecule activation, and the cleavage of the O–H bond in CH3OH has been proven to be the rate‐determining step for AB methanolysis. This work presents a versatile step‐growth strategy to prepare a vertically oriented PAF on GO to solve the stacking problem of 2D materials, which will be used to fabricate other novel 2D or 2D–2D materials with controllable orientation for various applications.

Highly active and stable CoWS2 catalysts in slurry phase hydrocracking of vacuum residue: XAFS studies

The bimetallic CoWS2 catalysts were prepared in situ during the slurry phase hydrocracking (HCK) of vacuum residue (VR) using W(CO)6 and Co-octoate as oil soluble precursors to investigate the promotional effect of Co promoters on the dispersed WS2 catalyst for the VR HCK. The morphologies and structural properties of dispersed catalysts were characterized by transmission electron microscopy (TEM) and X-ray absorption spectroscopy (XAS). The bimetallic CoWS2 catalyst was observed to form well-dispersed monolayers in the size range of 7–11 nm, which showed higher turn-over frequency values (TOF) and C7-asphaltene (C7-ASP) conversions than monometallic WS2 or Co9S8 catalysts in the VR HCK at 693 K and 10.0 MPa H2. Moreover, the extended X-ray fine absorption structure spectroscopy (EXAFS) coupled with the density functional theory (DFT) calculations successfully verified the formation of the Co-W-S phase.

Controllable synthesis of micro-mesoporous Pd@N-doped carbon derived from ZIF@NiCoLDH for enhanced phenol hydrogenation to cyclohexanone

A hollow nitrogen-doped carbon (CN) material, featuring abundant mesopores and high content of graphitic nitrogen, has been synthesized by annealing of the core-shell precursor composed of zeolitic imidazolate framework-67 as core and layered double hydroxides as shell. The proportion of mesopores and nitrogen species in the CN materials significantly vary with the shell thickness of layered double hydroxides in the core-shell precursor by adjusting the etching amount and etching time of nickel nitrate. The as-prepared Pd@CN-1.4–30 catalyst exhibits superior catalytic performance in the hydrogenation of phenol to cyclohexanone, and its turnover frequency (TOF) value is about ten times higher than Pd@CN obtained without the nickel etching, resulting from the abundant mesopores, high graphitic N content, and easy reduction of palladium species. Moreover, Pd@CN-1.4–30 has good reusability during at least six reaction cycles.

Spinel-Anchored Iridium Single Atoms Enable Efficient Acidic Water Oxidation via Intermediate Stabilization Effect

Iridium oxide is considered the only practical catalyst for oxygen evolution reaction (OER) in commercial proton exchange membrane (PEM) electrolyzers. However, its low activity and high cost greatly hinder the large-scale development of PEM electrolyzers for hydrogen production. Herein, we report atomically dispersed Ir atoms incorporated into a spinel Co3O4 lattice as an acidic OER catalyst, which exhibits excellent activity and stability for water oxidation. The catalyst significantly lowers the overpotential down to 226 mV at 10 mA cm–2 with an ultrahigh turnover frequency value of 3.15 s–1 (η = 300 mV), 3 orders of magnitude higher than that of commercial IrO2. Meanwhile, the catalyst shows superior corrosion resistance in an acidic OER condition, reaching a lifespan of up to 500 h at 10 mA cm–2. First-principles calculations reveal that the key *OOH intermediate can be stabilized by the lattice oxygen coordinated to the Ir active site via hydrogen bond formation, which substantially regulates the rate-limiting step and lowers the activation free energy of the OER process. This work demonstrates a strategy for improving the OER activity of Ir-based catalysts and provides insights into the regulation of the reaction mechanism.

Oxygen vacancy-engaged interfacial charge transfer modulation for upgrade Rh-catalyzed hydrogen and oxygen productions

Developing efficient modulation strategies to upgrade the catalytic activity and reusability of Rh-catalyzed hydrogen evolution from ammonia borane (AB) hydrolysis are definitely profitable but remains a grand challenge. Here, we develop a stepwise activation strategy to produce highly active and reusable Rh/CoFe2O4-SB-H2 with abundant oxygen vacancies and strong electronic metal-support interaction through stepwise reduction of Rh/CoFe2O4 precursor using sodium borohydride and H2 as the reducing agents. Under ultrasonic irradiation, Rh/CoFe2O4-SB-H2 with an ultralow Rh loading of 0.20 wt% can be utilized as an excellent catalyst for hydrogen production from room-temperature AB hydrolysis with a high turnover frequency (TOF) of 1894 min−1. The TOF value could be further promoted to 15,570 min−1 in the alkaline ultrasonic environment. The catalyst has a superior reusability with 75% maintaining activity of initial one in the 10th cycle. The strong electronic metal-support interaction, rich oxygen vacancies and ultrasound irradiation promote the oxidative cleavage of the O–H bonds in attracted H2O and thus account for high performance toward hydrogen production from AB. This catalyst can also be utilized as an active catalyst for oxygen generation from H2O2 decomposition. The developed strategies can be applied to upgrade the performance of other reducible metal oxides supported metal catalysts toward catalytic applications.

Metal-free and water-compatible nanocatalysts for green photocatalytic dehydrogenation in aqueous medium

Two types of poly-porphyrin-based heterogeneous photocatalysts including insoluble polymer and water-soluble nanoparticles exhibited excellent photocatalytic activity in visible-light-induced dehydrogenation in water. The extremely low catalyst loading (0.01 ​mol%) of water-soluble nanoparticles provided so far the highest turnover frequency (TOF) value (333 h-1) for such transformation among reported records.

Solventless Dimethylamine Borane Dehydrogenation in the Presence of Transition Metal(0) Nanoparticles Loaded on Cellulose

AbstractHerein, the results of in‐situ synthesis of four different metal(0) nanoparticles (Pd, Cu, Ru, and Ni) loaded on the surface of cellulose (MNPs@Cellulose) separately and their catalytic use in the solventless dimethylamine‐borane (DMAB) dehydrogenation at 35.0±0.1 °C are reported. Based on the detailed kinetic studies on the solventless DMAB dehydrogenation catalyzed using MNPs@Cellulose, the following results were obtained: (i) Optimum metal loading percentage on the surface of cellulose was determined for Pd@Cellulose to be 4.0 wt.%Pd (152.39 h−1), Ni@Cellulose to be 3.0 wt.%Ni (59.09 h−1), Cu@Cellulose to be 3.0 wt.%Cu (55.45 h−1) and Ru@Cellulose to be 4.0 wt.%Ru (46.06 h−1) and by determining total turnover frequency values in average 10th minutes (TOF10), which provided the highest catalytic activity. (ii) The optimum amount of cellulose for each metal was found to be 50.0 mg for Pd, Cu, and Ru, and 40.0 mg for Ni. (iii) The Arrhenius activation energies were determined for each metal nanoparticles and calculated to be 69±2, 34±2, 35±2 and 42±2 kj.mol−1 for Pd@Cellulose, Ni@Cellulose, Cu@Cellulose, and Ru@Cellulose, respectively.

Cobalt-Promoted Noble-Metal Catalysts for Efficient Hydrogen Generation from Ammonia Borane Hydrolysis.

Ammonia borane (AB) has been regarded as a promising material for chemical hydrogen storage. However, the development of efficient, cost-effective, and stable catalysts for H2 generation from AB hydrolysis remains a bottleneck for realizing its practical application. Herein, a step-by-step reduction strategy has been developed to synthesize a series of bimetallic species with small sizes and high dispersions onto various metal oxide supports. Superior to other non-noble metal species, the introduction of Co species can remarkably and universally promote the catalytic activity of various noble metals (e.g., Pt, Rh, Ru, and Pd) in AB hydrolysis reactions. The optimized Pt0.1%Co3%/TiO2 catalyst exhibits a superhigh H2 generation rate from AB hydrolysis, showing a turnover frequency (TOF) value of 2250 molH2 molPt-1 min-1 at 298 K. Such a TOF value is about 10 and 15 times higher than that of the monometal Pt/TiO2 and commercial Pt/C catalysts, respectively. The density functional theory (DFT) calculation reveals that the synergy between Pt and CoO species can remarkably promote the chemisorption and dissociation of water molecules, accelerating the H2 evolution from AB hydrolysis. Significantly, the representative Pt0.25%Co3%/TiO2 catalyst exhibits excellent stability, achieving a record-high turnover number of up to 215,236 at room temperature. The excellent catalytic performance, superior stability, and low cost of the designed catalysts create new prospects for their practical application in chemical hydrogen storage.

Bidirectional O2 reduction/H2O oxidation boosted by a pentadentate pyridylalkylamine copper(II) complex

The development of catalysts for oxygen reduction reaction (ORR) and water oxidation reaction (WOR) is important for promoting the utilization of renewable energy sources. Catalysts based on Earth-abundant metals are low-cost and benefit the widespread use. Herein a mononuclear copper complex [Cu(tpmen)](ClO4)2 (Cu-tpmen) of the pentadentate pyridylalkylamine ligand N,N,N’-tris(2-pyridylmethyl)-N’-methylethylenediamine (tpmen) was synthesized and characterized. The electrochemical properties and the catalysis for the ORR and the WOR by Cu-tpmen in aqueous solutions were studied. Cu-tpmen in pH 7.0 0.1 M phosphate buffer solution (PBS) can boost the ORR with an onset potential at 0.47 V versus the reversible hydrogen electrode (RHE), generating mainly H2O2. The foot-of-the-wave analysis showed that turnover frequency (TOF) of the reduction of O2 to H2O2 mediated by Cu-tpmen was 6.5 × 104 s−1. Meanwhile, Cu-tpmen exhibited catalytic activities for the WOR with the TOF values of 50.9 s−1 (at pH 7.0) and 8.4 s−1 (at pH 10.5). Cu-tpmen was thus a homogeneous bidirectional ORR/WOR catalyst and the reaction mechanisms were proposed. The synergic effect of the flexibility and the electron-donating ability of tpmen benefited the bidirectional catalytic properties of Cu-tpmen.

Role of the Support Oxidation State on the Catalytic Activity of Two-Dimensional Pt/TiOx Catalysts

The interaction between metal and support is known to substantially enhance catalytic activity. Herein, we investigate the effect of the support’s oxidation state on the metal–support interaction (MSI) with two-dimensional Pt/TiOx catalysts. Using titanium oxide supports with five different oxidation states and Pt nanoparticles deposited on the supports via arc plasma deposition, we accurately performed the CO oxidation reaction in a batch reactor. We confirmed that the catalyst whose support has the highest oxidation state exhibits the best catalytic activity. The catalysts’ turnover frequency value varied sequentially from 4.0 to 19.4 at 513 K, and the activation energy also varied sequentially from 23.90 to 19.13 kcal/mol depending on the oxidation states of the supports. Kinetic studies have shown that the additional reaction pathway following the Mars–van Krevelen mechanism formed at the metal–oxide interface, which was affected by the oxidation states of the supports. The compositional effects of the support were confirmed by X-ray photoelectron spectroscopy analysis: the MSI effect was maintained even after the surface of the titanium oxides completely oxidized.

Mononuclear nickel and copper complexes as electrocatalyst for generation of hydrogen from acetic acid

Ever increasing use of conventional energy and demand of clean renewable energy inspire many researchers to produce effective systems for hydrogen generation. Herein we report two mononuclear complexes, [NiL] (Complex 1) and [CuL] (Complex 2), where H2L is 1,1′-(1E,1′E)-(propane-1,2-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)dinaphthalen-2-ol, as electrocatalyst for hydrogen evolution reaction using acetic acid as the substrate. Both of the complexes have been synthesized under mild conditions and characterized by several methods. Single crystal X-ray structure of Complex 1 shows square planar geometry around nickel center. These complexes have effectively been used to reduce proton to generate hydrogen. Different control experiments have been carried out to understand the role of these catalysts and find their relevance in this regard. Turnover frequency (TOF) values for 1 and 2 have been determined as 653.1 and 777.5 s−1, respectively. Hydrogen is evolved via reduction of metal center followed by formation of metal hydride species.

Facile Synthesis of β-Tetracyano Vanadyl Porphyrin from Its Tetrabromo Analogue and Its Excellent Catalytic Activity for Bromination and Epoxidation Reactions.

Complex 2,3,12,13-tetracyano-5,10,15,20-tetraphenylporphyrinatooxidovanadium(IV) {[VIVOTPP(CN)4], 2} has been prepared by nucleophilic substitution of β-bromo groups of the corresponding 2,3,12,13-tetrabromo-5,10,15,20-tetraphenylporphyrinatooxidovanadium(IV) {[VIVOTPP(Br)4], 1} using CuCN in quinoline. Both complexes show biomimetic catalytic activity similar to enzyme haloperoxidases and efficiently brominate various phenol derivatives in the presence of KBr, H2O2, and HClO4 in the aqueous medium. Between these two complexes, 2 exhibits excellent catalytic activity with high turnover frequency (35.5-43.3 s-1) due to the strong electron-withdrawing nature of the cyano groups attached at β-positions and its moderate nonplanar structure as compared to 1 (TOF = 22.1-27.4 s-1). Notably, this is the highest turnover frequency value observed for any porphyrin system. The selective epoxidation of various terminal alkenes using complex 2 has also been carried out, and the results are good, specifying the importance of electron-withdrawing cyano groups. Catalysts 1 and 2 are recyclable, and the catalytic activity proceeds through the corresponding [VVO(OH)TPP(Br)4] and [VVO(OH)TPP(CN)4] intermediates, respectively.

Synthesis and characterization of titanium-substituted nanocrystalline Co2-Y hexaferrite: magnetically retrievable photocatalyst for treatment of methyl orange contaminated wastewater.

Rapid industrial growth causes considerable environmental havoc, adversely affecting human and aqueous life. It becomes a significant concern to deal with adequate wastewater treatment strategies by converging on water scarcity. This research work explored the synthesis of titanium-substituted Y-type barium hexaferrite (Co2-Y), having a general formula of Ba2Co2Fe12-xTixO22 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5), using a facile nitrate-based sol-gel auto-combustion route and its suitability was investigated as a heterogeneous catalyst within the photo-Fenton-based degradation of methyl orange (MO), one of the significant pollutants generated from textile industries. Developing a thermochemically stable and magnetically separable heterogeneous catalyst for photocatalytic decomposition of nonbiodegradable organic dye from wastewater was also emphasized. The as-prepared nanocrystalline Co2-Y powders were analyzed using XRD, FTIR, DLS, UV-visible spectroscopy, SEM, VSM, and XPS. Furthermore, the photocatalytic degradation performance of pristine and titanium substituted Ba2Co2Fe11.6Ti0.4O22 ferrite, having the lowest bandgap value among all samples, was quantified and compared in terms of apparent rate constant (karc) value and turnover frequency values. The enriched photocatalytic performance was correlated with the existence of multi-valance states of transition metal cations and the availability of oxygen vacancy, confirmed by the surface chemistry using the XPS analysis. The modified (enhanced thermal and chemical stability) hexaferrite catalyst was magnetically separable and reusable without significant losses to its catalytic performance. This promising catalyst may be considered as a replacement for soft ferrite materials to catalyze the degradation of several other nonbiodegradable organic pollutants from wastewater in large-scale industries.

Stable and Ordered Body-Centered Cubic PdCu Phase for Highly Selective Hydrogenation.

Phase engineering of nanomaterials plays a crucial role for regulating the catalytic performance. Nevertheless, great challenges still remain for elucidating the structure-selectivity correlation. Herein, this study demonstrates that the body-centered cubic phase of PdCu (bcc-PdCu) can serve as a highly active and selective catalyst for 3-nitrostyrene (NS) hydrogenation under mild conditions. In particular, bcc-PdCu displays a 3-nitro-ethylbenzene (NE) selectivity of 93.8% with a turnover frequency (TOF) value of 4573 h-1 at 30°C in the presence of H2 . With the assistance of NH3 ∙BH3 , the selectivity of 3-amino-styrene (AS) reaches 94.5% with a TOF value of 13719h-1 . Detailed experimental and theoretical calculations reveal that improved NE selectivity is ascribed to the selective adsorption of the CC bond and desorption of NE on bcc-PdCu. Moreover, the presence of NH3 ∙BH3 facilitates the selective hydrogenation of NO2 due to their strong interaction and thus leads to the formation of AS. This work provides an efficient selective catalyst for NS hydrogenation under mild conditions, which may attract immediate interests in the fields of materials, chemistry, and catalysis.

Enhanced Activity of WOx-Promoted PdNi Nanoclusters Confined by Amino-Modified KIT-6 for Dehydrogenation of Additive-Free Formic Acid

Formic acid (FA, HCOOH), featured as a major liquid product of biomass processing and especially a liquid sunshine carrier, thus becomes a renewable and promising liquid organic hydrogen carrier. It is highly desirable, but it remains a big challenge to develop a highly active heterogeneous catalyst with no or low content of noble metals for dehydrogenation of additive-free FA at ambient conditions. Herein, for the first time, WOx-modified PdNi alloy nanoclusters immobilized by amino-functionalized KIT-6 (PdNi-WOx/KIT-6-NH2) are prepared through a simple and facile strategy at ambient conditions. PdNi-WOx clusters with an ultrasmall size of 1.4 nm are highly dispersed onto KIT-6-NH2 support. The strong electronic coupling in PdNi-WOx NCs and electronic metal–support interaction between PdNi-WOx NCs and KIT-6-NH2 support lead to the formation of electron-rich PdNi of PdNi-WOx/KIT-6-NH2. The resulting PdNi-WOx/KIT-6-NH2 catalyst exhibits highly efficient catalytic activity and 100% hydrogen selectivity for formic acid dehydrogenation without extra additives, giving turnover frequency (TOF) values of 1699 h–1 at 303 K and 4417 h–1 at 323 K, which is higher than most of the heterogeneous catalysts ever reported. Kinetic isotope effect investigation clearly shows that C–H bond cleavage is the rate-determining step for PdNi-WOx/KIT-6-NH2. This work provides a new insight into designing low-cost and efficient heterogeneous catalysts for dehydrogenation of formic acid.

Efficient catalytic performance of Ru nanoparticles for hydrogen generation from NH3BH3: The dual role of Mo oxide

Ru nanoparticles doped and supported by Mo oxide (Ru/Mo oxide NPs) were synthesized via an in situ co-precipitation strategy for hydrogen production via hydrolysis of ammonia borane (AB). The optimized Ru0.9Mo0.1 catalyst composition exhibited a total turnover frequency (TOF) value of 514.8 molH2 (molRu0.9Mo0.1)−1 min−1 at room temperature. Systematic characterization of the catalysts unveiled the dual role of Mo oxide in regulating the structure and catalytic performance of Ru NPs. This work provides a new approach for the design of Ru-based nanocatalysts toward hydrolysis of AB for H2 harvest.

Two Novel Schiff Base Manganese Complexes as Bifunctional Electrocatalysts for CO2 Reduction and Water Oxidation.

One mononuclear Mn(III) complex [MnIIIL(H2O)(MeCN)](ClO4) (1) and one hetero-binuclear complex [(CuIILMnII(H2O)3)(CuIIL)2](ClO4)2·CH3OH (2) have been synthesized with the Schiff base ligand (H2L = N,N'-bis(3-methoxysalicylidene)-1,2-phenylenediamine). Single crystal X-ray structural analysis manifests that the Mn(III) ion in 1 has an octahedral coordination structure, whereas the Mn(II) ion in 2 possesses a trigonal bipyramidal configuration and the Cu(II) ion in 2 is four-coordinated with a square-planar geometry. Electrochimerical catalytic investigation demonstrates that the two complexes can electrochemically catalyze water oxidation and CO2 reduction simultaneously. The coordination environments of the Mn(III), Mn(II), and Cu(II) ions in 1 and 2 were provided by the Schiff base ligand (L) and labile solvent molecules. The coordinately unsaturated environment of the Cu(II) center in 2 can perfectly facilitate the catalytic performance of 2. Complexes 1 and 2 display that the over potentials for water oxidation are 728 mV and 216 mV, faradaic efficiencies (FEs) are 88% and 92%, respectively, as well as the turnover frequency (TOF) values for the catalytic reduction of CO2 to CO are 0.38 s-1 at -1.65 V and 15.97 s-1 at -1.60 V, respectively. Complex 2 shows much better catalytic performance for both water oxidation and CO2 reduction than that of complex 1, which could be owing to a structural reason which is attributed to the synergistic catalytic action of the neighboring Mn(III) and Cu(II) active sites in 2. Complexes 1 and 2 are the first two compounds coordinated with Schiff base ligand for both water oxidation and CO2 reduction. The finding in this work can offer significant inspiration for the future development of electrocatalysis in this area.