Cobalt Metal-organic Framework Research Articles

Molybdenum nitride thin films coated cobalt-metal-organic framework nanocolumns for high-efficiency alkaline hydrogen evolution

The sustainable development of catalysts with Pt-like catalytic activity to produce hydrogen economically from water electrolysis is essential and challenging. Herein, we have prepared a novel catalyst with the combined virtues of nanocolumn structures and heterojunctions by magnetron sputtering molybdenum nitride (Mo2N) thin films over cobalt-metal-organic framework (Co-MOF) nanocolumns on carbon paper (CP), and explored the catalytic activities in hydrogen evolution reaction (HER). By optimizing the preparation process, the heterostructured Co-MOF@Mo2N/CP catalysts can exhibit an excellent HER performance with an overpotential of only 72.8 mV at 10 mA cm-2 and cycling durability over 24 h and 5000 cycles, achieving one of the best performances among state-of-the-art Mo-based catalysts. This work guides and accelerates the design of low-cost and high-performance transition metal nitrides HER catalysts for industrial applications.

Magnetic cobalt metal organic framework for photocatalytic water splitting hydrogen evolution

Using water as a renewable and safe energy source for hydrogen generation has reduced the need to use toxic fossil fuels. Photocatalytic approaches provide a worthy solution to avoid the high expenditure on complicated electrochemical pathways to promote Hydrogen Evolution Reactions. However, several types of photocatalysts including noble metal-based catalysts have already been in use for this purpose, which are generally considered high-cost as well. The present study aims to use the benefits of metal–organic frameworks (MOFs) with semiconductor-like characteristics, highly porous structures and high design flexibility. These properties of MOFs allow more efficient and effective mass transport as well as exposure to light.in this paper, using MOF technology and benefiting from the characteristics of Fe3O4 nanoparticles as catalyst support for more efficient separation of catalyst, we have synthesized a novel composite. Our proposed photocatalyst demonstrates efficient harvest of light in all wavelengths from UV to visible to generate electron/hole pairs suitable for water splitting with a turnover frequency of 0.222 h−1 at ambient conditions without requiring any additives.Graphical abstract

Chitosan-based GOx@Co-MOF composite hydrogel: A promising strategy for enhanced antibacterial and wound healing effects

A novel composite hydrogel was synthesized via Schiff base reaction between chitosan and di-functional poly(ethylene glycol) (DF-PEG), incorporating glucose oxidase (GOx) and cobalt metal-organic frameworks (Co-MOF). The resulting CS/PEG/GOx@Co-MOF composite hydrogel was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and energy-dispersive X-ray spectroscopy (EDS). The results confirmed successful integration and uniform distribution of Co-MOF within the hydrogel matrix. Functionally, the hydrogel exploits the catalytic decomposition of glucose by GOx to generate gluconic acid and hydrogen peroxide (H2O2), while Co-MOF gradually releases metal ions and protects GOx. This synergy enhanced the antibacterial activity of the composite hydrogel against both Gram-positive (S. aureus) and Gram-negative bacteria (E. coli), outperforming conventional chitosan-based hydrogels. The potential of the composite hydrogel in treating wound infections was evaluated through antibacterial and wound healing experiments. Overall, CS/PEG/GOx@Co-MOF hydrogel holds great promise for the treatment of wound infections, paving the way for further research and potential clinical applications.

A novel hierarchic hydrothermal strategy to enhance the performance of nickel-cobalt metal-organic framework for supercapacitors

The study presents a novel hierarchical hydrothermal strategy, which can not only ensure the morphology characteristics of the initial hydrothermal products, but also enhance the properties of the materials. Here, the hierarchical hydrothermal treatment was carried out with bimetallic nickel cobalt metal organic framework (NiCo-MOF) as the representative. The results of characterization and electrochemical tests showed that NiCo-MOF after hierarchical hydrothermal treatment (NCM-H) not only exhibits enhanced stability in crystal morphology but also an increased number of active sites in the material. At the same time, compared with the initial hydrothermal NiCo-MOF (NCM-F), the rate performance and cycle stability of NCM-H have been greatly improved. The prepared NCM-H electrode demonstrates a remarkable specific capacity of 1006F g−1 at 1 A/g. Furthermore, the assembled NCM-H//AC asymmetric supercapacitor (ASC) device demonstrates a remarkable energy density of 100.8 Wh kg−1 at a power density of 750 W kg−1. Excellent rate performance (76.4 % retention from 1 A/g to 20 A/g) and cycling stability (83.8 % after 5000 cycles). This unique hierarchical hydrothermal strategy is convenient, efficient, environmentally friendly and low-cost, and can provide a meaningful reference for the performance improvement of MOF-based and other related materials.

Synthesis of HER-capable cobalt metal organic framework using a straightforward reflux method and a thorough spectroscopic and theoretical analysis

A Cobalt MOF was obtained under reflux using aqueous methanol. The Cobalt MOF was synthesized using Cobalt (II) perchlorate hexahydrate and 1,3,5-Benzenetricarboxylic Acid (BTC) in a methanol mixed with double distilled water as a solvent under reflux condition for 2–3 h at 60–65 °C. The reddish solution obtained was filtered and kept in the refrigerator for almost 24 h. A crystal suitable for SC-XRD was obtained and the XRD analysis confirmed the polymeric structure of the Co-BTC. All the other analysis such as FTIR, Thermal analysis and FESEM of Co-BTC was carried out. Further, the efficacy of it as a potential catalyst towards HER was explored. The theoretical study assisted, and the data suggests that low band gap of the MOF possibly favors its efficacy in the Hydrogen Evolution Reaction (HER).

The hierarchical dense structure induced high stability to NiCoB-based electrode for electrochemical energy storage

The construction of stable hierarchical surfaces through structural engineering is the key to improve reactive active sites and cycle stability to achieve high cycle performance of supercapacitors (SCs). In this work, the NiCo-LDH nanoflower as a structure guide agent was used to support NiCoB nanosheets to form a dense and stable hierarchical structure, thereby exposing more active sites and improving cycle stability. Due to the hierarchical stable surface structure, the NiCoB-0.3@NiCo-LDH-30 electrode has an excellent specific capacitance of 2710F g−1 at 1 A/g due to the excellent electrochemical active surface area (1259 mF cm−2), improving the OH– diffusion coefficient (2.4 × 10−9 cm2 s−1) and decreasing ionic diffusion barrier. After 5000 cycles, NiCoB-0.3@NiCo-LDH-30 electrode still has 92.6 % initial specific capacitance. In order to balance the energy density decrease caused by the capacitance imbalance between positive and negative electrodes, the cubed carbon (Co-C) derived from cobalt metal organic frameworks (Co-MOFs) as cathode with a good specific capacitance of 220F g−1 at 1 A/g is prepared. The assembled NiCoB-0.3@NiCo-LDH-30//Co-C hybrid SCs (HSCs), which are assembled with NiCoB-0.3@NiCo-LDH-30 electrode as anode and Co-C electrode as cathode, displays an energy density of 75 Wh kg−1 at a power density of 741 W kg−1.

Dual-confinement regulating ternary metal-oxide activity sites derived from Co-MOF for enhanced electrocatalytic activity for glucose oxidation

Based on a dual-confinement strategy on a cobalt-metal-organic framework (Co-MOF), a series of trimetallic-oxide catalysts of Cux-O-Niy-O-Co3-x-y (x/y = 1/1, 1/3, 1/5 and 1/7) were developed for glucose oxidation. By chemical confinement regulation of ion exchange, diverse metal catalytic sites of Cu2+ and Ni2+ were introduced into Co-MOF, respectively; Then by spatial confinement synthesis of pyrolysis, trimetallic MOF of CuxNiyCo3-x-y-MOF was transformed into trimetallic-oxide of Cux-O-Niy-O-Co3-x-y, which maintained the regular morphology and highly ordered lattice structure of Co-MOF. The Cux-O-Niy-O-Co3-x-y composite modified glassy carbon electrode (Cux-O-Niy-O-Co3-x-y/GCE) exhibited enhanced electrocatalytic activity towards glucose oxidation when compared with Co-MOF/GCE, bimetallic MOFs of CuCo-MOF/GCE and NiCo-MOF/GCE, trimetallic MOF of CuxNiyCo3-x-y-MOF/GCE, as well as monometallic oxide Co3O4/GCE and bimetallic oxides of CuCo2O4/GCE and NiCo2O4/GCE, which was mainly due to the synergistic catalysis of electrocatalytically active Co-O-Cu-O-Ni bridges. With Cu2+/Ni2+ molar ratio of 1/3, Cux-O-Niy-O-Co3-x-y/GCE (x/y = 1/3) displayed excellent sensing behaviours on glucose detection. This work not only designed well-performed electrocatalysts for enhancing catalytic activity towards glucose oxidation, but also provided a new perspective to realize the controlled preparation of high-performance electrocatalysts.

Sulfonated Cobalt Metal-Organic Framework Embedded Mixed Matrix Membrane towards Fuel-Cell Applications.

New strategies for enhancement of the fuel-cell performance of a poly(2,5-benzimidazole) (ABPBI) membrane loaded with a functionalized cobalt-based metal-organic framework (MOF) for H2-O2 fuel cells. ABPBI was prepared using the polycondensation method, and various proportions of sulfonated cobalt MOF (sCo-MOF) were incorporated into ABPBI to fabricate a proton-exchange membrane (PEM). Later, the fabricated membranes were soaked in 1 M sulfuric acid to produce sulfonated PEMs. The developed composite membranes had increased proton conductivity, tensile strength, physicochemical properties, and fuel-cell performance compared to the sulfonated ABPBI (sABPBI) membrane. A membrane embedded with 4 wt % sCo-MOF shows higher water uptake and ion-exchange capacity values of 23.25% and 2.89 mequiv g-1, respectively. The membrane electrode assemblies were fabricated to perform unit-cell tests for both sABPBI and 4 wt % sCo-MOF/sABPBI membranes. The 4 wt % sCo-MOF-loaded sABPBI membrane demonstrated good unit-cell performance in the fuel-cell test, with a power density of 415.8 mW cm-2 at 80 °C, superior to the pristine sABPBI membrane's power density of 178.6 mW cm-2.

CTAB-Co-MOFs@AuPt NPs as signal probes for the electrochemical detection of carcinoembryonic antigen 15-3.

A sensitive electrochemical strategy for carcinoembryonic antigen 15-3 (CA15-3) detection isreported using CTAB-Co-MOFs@AuPt NPs as signal probes. The electrochemical strategy was designed as follows: First, the graphene aerogel@gold nanoparticles (GA@Au NPs) nanocomposites were employed to modify the sensing surface for promoting electron transfer rate and primary antibody (Ab1) immobilization due to GA possesses a large specific surface area, eminent conductivity, and a 3D network structure. Cobalt metal-organic frameworks (CTAB-Co-MOFs) synthesized were then used as a carrier for AuPt NPs and secondary antibody (Ab2) immobilization (notes: labelled-Ab2). With sandwich immunoreaction, the labelled-Ab2 was captured on the surface of the GA@Au NPs nanocomposites. Finally, differential pulse voltammetry (DPV) was employed to register the electrochemical signal of the immunosensor at the potential of - 0.85V (vs SCE) in phosphate buffer saline (PBS) containing 2.5mM H2O2. It was verified that the electrochemical reduction signal from Co3+ to Co2+ was recorded. The AuPt NPs could catalyze the reaction of H2O2 oxidizing Co2+ to Co3+, resulting in the amplification of the electrochemical signal. Under the selected conditions, the immunosensor can detect CA15-3 in the range10 µU/mL to 250 U/mL with a low detection limit of 1.1 µU/mL. In the designed strategy, the CTAB-Co-MOFs were not only employed as carriers for AuPt NPs, but also acted as signal probes. The CTAB-Co-MOFs were investigated including SEM, TEM, XPS, and XRD. The applicationability of theimmunosensor was evaluated using serum sample, demonstrating the immunosensor can be applied to clinic serum analysis.

A facile strategy of designing a new crystalline cobalt metal–organic framework as a new efficient and robust heterogeneous catalyst for olefin oxidation reaction

A novel three-dimensional (3D) metal-organic compound Co3(BDC)3(DMF)2(H2O)4.2DMF (DMF= N,N-dimethylformamide; BDC= 1,4-benzenedicarboxylate) (Co-BDC (1)) has been synthesized under solvothermal method using Co2+ salt and BDC as a rigid ligand. The material was structurally characterized by single-crystal X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR), thermogravimetric (TGA), inductively coupled plasma (ICP), and elemental (CHN) techniques. Oxidation of some olefins was evaluated with tert‑butyl hydroperoxide (TBHP) in acetonitrile in the presence of Co-BDC (2) (activated Co-BDC (1)) as a heterogeneous catalyst. Among the substrates used for the oxidation reaction, desirable conversions of 97 %, 81.6 %, and 76 % were obtained for cyclooctene, 1-hexene, and norbornene, respectively. Finally, the catalyst was recycled and reused (four times) without a remarkable decrease in the catalytic activity.

Fabrication of graphene-based magnetic carbon composites derived from iron cobalt metal-organic framework as dual-band electromagnetic wave absorbers

The fabrication of advanced magnetic carbon electromagnetic wave (EMW) absorbers derived from metal-organic framework (MOF) with thin thickness, wide bandwidth, strong absorption strength and low filling ratio remains a huge challenge. In this paper, CoFe2O4/CoFe/C/Graphene composites were prepared by a simple two-step way of solvothermal reaction and carbonization treatment. The results of micromorphology analysis revealed that as the carbonization temperature increased, the obtained carbon frameworks changed from a spindle shape to dodecahedron-like shape and finally to a tile shape, and the carbonization temperature had a notable influence on the electromagnetic parameters and EMW absorption properties of the magnetic carbon composites. It should be noted that the obtained CoFe2O4/CoFe/C/Graphene composites exhibited comprehensive excellent EMW absorption performance when the carbonization temperature was 750.0 ℃ and the filling radio was only 15.0 wt%, namely the effective absorption bandwidth reached up to 4.8 GHz and the optimal minimum reflection loss was −40.2 dB at a thickness of 2.06 mm. A distinct dual-band (C band and Ku band) absorption feature was observed when the thickness exceeded or equaled 4.5 mm. Furthermore, the underlying electromagnetic dissipation mechanisms were also elucidated. Therefore, our results could provide a valuable reference for preparing excellent magnetic carbon EMW absorbers derived from MOF.

Bioelectrocatalytic reduction by integrating pyrite assisted manganese cobalt-doped carbon nanofiber anode and bacteria for sustainable antimony catalytic removal

A novel manganese cobalt metal–organic framework based carbon nanofiber electrode (MnCo/CNF) was prepared and used as microbial fuel cell (MFC) anode. Pyrite was introduced into the anode chamber (MnCoPy_MFC). Synergistic function between pyrite and MnCo/CNF facilitated the pollutants removal and energy generation in MnCoPy_MFC. MnCoPy_MFC showed the highest chemical oxygen demand removal efficiency (82 ± 1%) and the highest coulombic efficiency (35 ± 1%). MnCoPy_MFC achieved both efficient electricity generation (maximum voltage: 658 mV; maximum power density: 3.2 W/m3) and total antimony (Sb) removal efficiency (99%). The application of MnCo/CNF significantly enhanced the biocatalytic efficiency of MnCoPy_MFC, attributed to its large surface area and abundant porous structure that provided ample attachment sites for electroactive microorganisms. This study revealed the synergistic interaction between pyrite and MnCo/CNF anode, which provided a new strategy for the application of composite anode MFC in heavy metal removal and energy recovery.

Construction of MOFs derived porous carbon based core–shell hetero-structure electrode for superior asymmetric supercapacitor

The design of electrode materials with high performance is very important to improve the energy density of supercapacitors (SCs). The combination of electrical double layer capacitor and pseudo-capacitive materials can significantly improve the electrochemical performance of material, but reasonable structural design can inhibit the slow Faraday dynamic mismatch caused by different storage mechanisms. In this study, NiCoB nanosheets were grown on the surface of cobalt metal-organic frameworks (Co-MOF) derived porous carbon (Co-C) by chemical precipitation method to form a core–shell hetero-structure Co-C@NiCoB electrode. The Co-C@NiCoB electrode has the specific capacitance of 2990 F g−1 at 1 A g−1, which is significantly higher than that of Co-C (416 F g−1) and NiCoB (1052 F g−1). In order to further increase the energy density of the device, the carbon nano-sheets with cactus shape as cathode were obtained by calcination of Co-MOF (CNS). The asymmetric SCs with CNS as cathode and Co-C@NiCoB as anode have a high energy density of 66.03 Wh kg−1 at the power density of 763.35 W kg−1 and exceptional cycling life with capacitance retention of 92.1 % over 10,000 cycles.

Two-mode sensing strategies based on tunable cobalt metal organic framework active sites to detect Hg2+

Heavy metal pollution poses a major threat to human health, and developing a user-deliverable heavy metal detection strategy remains a major challenge. In this work, two-mode Hg2+ sensing platforms based on the tunable cobalt metal-organic framework (Co-MOF) active site strategy are constructed, including a colorimetric, and an electrochemical assay using a personal glucose meter (PGM) as the terminal device. Specifically, thymine (T), a single, adaptable nucleotide, is chosen to replace typical T-rich DNA aptamers. The catalytic sites of Co-MOF are tuned competitively by the specific binding of T-Hg2+-T, and different signal output platforms are developed based on the different enzyme-like activities of Co-MOF. DFT calculations are utilized to analyze the interaction mechanism between T and Co-MOF with defect structure. Notably, the two-mode sensing platforms exhibit outstanding detection performance, with LOD values as low as 0.5 nM (colorimetric) and 3.69 nM (PGM), respectively, superior to recently reported nanozyme-based Hg2+ sensors. In real samples of tap water and lake water, this approach demonstrates an effective recovery rate and outstanding selectivity. Surprisingly, the method is potentially versatile and, by exchanging out T-Hg2+-T, can also detect Ag+. This simple, portable, and user-friendly Hg2+ detection approach shows plenty of promise for application in the future.

Enhancing dye degradation using a novel cobalt metal-organic framework as a peroxymonosulfate activator.

Among transition metals, cobalt ions exhibit superior catalytic activity in the peroxymonosulfate (PMS) degradation of pollutants. However, practical application is hindered by their high rate of ion leaching and the propensity for particle reunion issues. In this study, a novel cobalt metal-organic framework catalyst, denoted as CUST-565 ([Co3(BTB)2(BIPY)2]·4.5H2O·DMA), was synthesized via a one-step solvothermal method. The obtained crystal was employed as a catalyst to activate PMS for degrading two pollutants, methyl orange (MO) and rhodamine B (RhB), in wastewater. The catalyst demonstrated efficacy in PMS, achieving 97% degradation of MO and 98% degradation of RhB within 30 min at an initial concentration of 20.0 mg L-1. Additionally, various factors affecting dye degradation, including PMS dosage, catalyst dosage, temperature, initial pH, and coexisting anions, were investigated. Radical quenching experiments confirmed the presence of sulfate radicals (SO4˙-), hydroxyl radicals (HO˙), superoxide radicals (O2˙-), and singlet oxygen (1O2) in the system. After four cycles, CUST-565 retained its ability to catalytically degrade approximately 80% of the pollutants. These observed stability and reusability properties, corroborated by a series of characterization analyses before and after use, suggest that CUST-565 exhibits reliable performance. This work contributes to the development of cobalt-PMS catalysts for efficiently degrading dyes in wastewater.

Controllable defect engineering based on cobalt metal-organic framework for boosting oxygen evolution reaction

Defect engineering on metal-organic frameworks (MOFs) provides high flexibility to rationally design advanced oxygen evolution reaction (OER) catalysts with low overpotential and high stability. However, fundamental understanding the effect of defect concentration on catalytic OER activity is still quite ambiguous. Herein, the Co-MOF-Dx catalysts with regulated oxygen defects concentration are deliberately constructed via coupling one-pot solvothermal synthesis with NaBH4 chemical reduction process. Experimental findings propose that the oxygen defect concentration within Co-MOF-Dx gradually increases with raising the NaBH4 content, which could provide a flexible platform to tailor the electronic structure around active Co site and optimize adsorption/desorption capacity of oxygen intermediates. When the introduction content of NaBH4 is up to 5 mg, the resulting abundant unsaturated coordination defects could endow the Co-MOF-D5 catalyst with optimized electronic structure and more exposed active sites for improving charge transfer and adsorption/desorption capacity. It is found that the optimized Co-MOF-D5 can drive the current density of 10 mA cm−2 only at a low overpotential of 300 mV with the small Tafel slope of 53.1 mV dec−1 in alkaline medium. This work sheds light on the way for the development of high-performance MOF catalysts via modulating defect concentration.

Facile synthesis of cobalt, nickel and manganese-based metal organic framework derived layered double hydroxides on Ni foam as effective binder-free electrodes of energy storage devices

Metal organic framework (MOF) derivatives have attracted intensive attention as the active material of energy storage devices. Layered double hydroxide (LDH) with large surface area, high redox capability and good cycling stability is regard as one of efficient active materials. Developing MOF-derived LDH with multiple metals can possibly achieve excellent surface properties, high electrical conductivity and abundant redox reactions. However, synthesizing MOF-derived LDH is time-consuming and requires high temperature environments. In this work, a simple and time-effective precipitation and etching process is proposed to synthesize MOF-derived LDH on nickel foam (NF) as binder-free electrodes of energy storage devices. The cobalt, nickel and manganese are utilized to design MOF-derived LDH with different metal species and numbers. The trimetallic MOF-derived LDH based on Co, Ni and Mn presents a high specific capacitance (CF) of 1113.7 F/g at 20 mV/s, due to abundant electroactive sites and multiple redox states for carrying out large numbers of redox reactions. The energy storage device composed of the trimetallic MOF-derived LDH and carbon on NF as electrodes presents the maximum energy density of 61.5 Wh/kg at the power density of 750 W/kg, and the CF retention of 92.5% and Coulombic efficiency of 95% after 10,000 charge/discharge cycles.

Sustainable Hierarchically Porous Reusable Metal–Organic Framework Sponge as a Heterogeneous Catalyst and Catalytic Filter for Degradation of Organic Dyes

Advanced oxidation processes based on sulfate radical are considered one of the most promising wastewater treatment technologies currently. Among heterogeneous catalysts, cobalt metal–organic framework (MOF) has been widely reported. However, the inherent powder form of MOF hinders its practical application and reusability. Therefore, innovative methods to increase the loading capacity and the accessibility of MOF active sites in monolithic materials are required. Therefore, a simple and scalable method of fabricating a stable, hierarchical porous zeolitic imidazolate framework (ZIF‐67) 3D sponge by growing MOF on a short electrospun fiber network is shown. The sponge can efficiently activate peroxymonosulfate and rapidly degrade an exemplary organic dye (Rhodamine B) with a degradation efficiency of 100%. The resulting multilevel, hierarchical porous structure is beneficial to the mass transfer of reagents making the catalytic process efficient. This also enables the use of the ZIF‐67 as an efficient catalytic filter for continuous removal of dye. The sponge can be recycled and reused for several cycles due to its robustness without loss in efficiency. The proposed research strategy provides a new way to design MOF 3D monolithic materials.

Enhanced cobalt MOF electrocatalyst for oxygen evolution reaction via morphology regulation

Developing productive and stable catalysts using common elements for the production of hydrogen via water splitting is highly desirable. Due to their well-designed composition, unique morphology, and highly crystalline structure, metal–organic frameworks (MOFs) exhibit good electrocatalytic performance and have attracted significant research interest as OER catalysts. The optimized Co-MOF-C catalyst reported herein exhibited a smaller overpotential at 10 mA cm−2 and Tafel slope (342 mV, 119 mV dec−1) than Co-MOF-A and Co-MOF-B in an alkaline solution for OER. Moreover, Co-MOF-C showed better long-term durability and stability with negligible deactivation compared with the other MOF catalysts. The apparent laminar nanomorphology of Co-MOF-C provided more accessible active metal centers, better electrical conductivity, and improved kinetics, explaining its better performance as an OER electrocatalyst.

A "Trinity" Design of Li-O2 Battery Engaging the Slow-Release Capsule of Redox Mediators.

Nonaqueous Li-O2 battery (LOB) represents one of the promising next-gen energy storage solutions owing to its ultrahigh energy density but suffers from problems such as high charging overpotential, slow redox kinetics and Li anode corrosion etc., calling for a systemic optimization of the battery configuration and structural components. Herein, an ingenious "trinity" design of LOB is initiated by implementing a hollowed cobalt metal organic framework (MOF) impregnating iodized polypyrrole simultaneously as the cathode catalyst, anode protection layer and slow-release capsule of redox mediators, so as to systemically address issues of impeded mass transport and redox kinetics on the cathode, dendrite growth and surface corrosion on the anode, as well as limited intermediate solubility in the low donor-number (DN) solvent. As a result of the systemic effort, the LOB constructed demonstrates an ultralow discharge/charge polarization of 0.2V, prolonged cycle life of 1200h and total discharge capacity of 28.41 mAh cm-2 . Mechanistic investigations attribute the superb LOB performance to the redox-mediated solution growth mechanism of crystalline Li2 O2 with both enhanced reaction kinetics and reversibility. This study offers a paradigm in designing smart materials to raise the performance bar of Li-O2 battery towards realistic applications. This article is protected by copyright. All rights reserved.