Zn Mn Batteries Research Articles

Reversible Zn and Mn deposition in NiFeMn-LDH cathodes for aqueous Zn-Mn batteries.

Introducing NiFeMn-Layered Double Hydroxide (LDH) as an innovative cathode material for Zn-Mn batteries, this study focuses on bolstering the electrochemical efficiency and stability of the system. We explored the effect of varying Zn/Mn molar ratio in the electrolyte on the battery's electrochemical performance and investigated the underlying reaction mechanism. Our results show that an electrolyte Zn/Mn molar ratio of 4 : 1 achieves a balance between capacity and stability, with an areal capacity of 0.20 mA h cm-2 at a current of 0.2 mA and a capacity retention rate of 53.35% after 50 cycles. The mechanism study reveals that during the initial charge-discharge cycle, NiFeMn-CO3 LDH transforms into NiFeMn-SO4 LDH, which then absorbs Zn2+, Mn2+, and SO4 2- ions to form a stable composite substrate. This substrate enables the reversible deposition-dissolution of Mn ions, while Zn ions participate in the reaction continuously, with most Mn- and Zn-containing compounds depositing in an amorphous phase. Although further optimization is needed, our findings provide valuable insights for developing Zn-Mn aqueous batteries, highlighting the potential of LDHs as cathode substrates and the pivotal role of amorphous compounds in the reversible deposition-dissolution process.

Hydroxylated Manganese Oxide Cathode for Stable Aqueous Zinc‐Ion Batteries

AbstractManganese (Mn) oxides are promising cathode materials for rechargeable aqueous Zn‐ion batteries. However, the Mn dissolution in weakly acidic electrolytes always hinders the development of better aqueous Zn–Mn batteries. Herein, a hydroxylated manganese oxide cathode material (H‐MnO2) is fabricated using an electrochemical method for stable aqueous Zn–Mn batteries without relying on the Mn2+ electrolyte additives. The partial hydroxylation of the oxides leads to charge redistribution of the material, changing the reaction thermodynamics and kinetics. Theoretical simulation suggests that the hydroxylation of manganese oxide promotes both Zn2+ adsorption thermodynamics and diffusion kinetics on the surface of H‐MnO2 but weakens the interaction between H+ and the electrode. Therefore, Zn2+ ions can be more reactive with the hydroxylated manganese oxide than H+ ions. Experimental results show that the Zn2+ insertion mechanism dominates the charge storage process of H‐MnO2, and the H+‐induced Mn dissolution reaction is effectively alleviated. Importantly, H‐MnO2 exhibits good cycling stability with 95% capacity retention over 5000 cycles at the current density of 3.8 A g−1 in the ZnSO4 electrolyte, outperforming the state‐of‐the‐art aqueous Zn–Mn batteries, even those with Mn2+ electrolyte additives. The findings provide new insights for designing stable manganese oxide cathodes in aqueous Zn–Mn batteries.

Interfacial structuring of Mn[sbnd]N and Mn[sbnd]C bonds by defect engineering for high-performance Zn-Mn battery

Zinc‑manganese batteries (ZMBs), with their non-flammable aqueous electrolyte and lower electrode material costs, offer a safer and more economical solution to the problem of energy intermittency. However, current ZMBs still face significant challenges, such as the presence of low electrical conductivity and poor structural stability of the manganese-based cathode, as well as unclear mechanisms of structural changes during charge storage. Here, we present a strategy to construct MnO2 containing MnC and MnN bonds (PAMO) by defect engineering and interface bonding design. This strategy benefits from the fact that MnN and MnC bonds can stabilize the structure and promote the interfacial dynamics of MnO2, thus effectively mitigating manganese dissolution. Meanwhile, the oxygen defects generated by interfacial bonding increase the electrical conductivity of MnO2. In addition, in terms of morphology and structure, the leafy vein-like secondary compartmentalized structure formed by PAMO provides more reactive sites for the redox reaction of MnO2, accelerating charge transfer and ion diffusion. The experimental results show that compared with pure MnO2 (326.8 mAh g−1), the capacity of PAMO material is enhanced by 30.1% (426.6 mAh g−1), and the battery still has 85.4% residual capacity (144.2–123.1 mAh g−1) after 6000 cycles, and coulombic efficiency is always maintained above 99.5%. This heterostructure design strategy of C- and N-doped MnO2 provides high electronic conductivity while playing an important role in improving structural stability.

A New Design Strategy Enables High Mn‐Utilization Rate in Aqueous Zinc–Manganese Batteries: Constructing Cathodic Local Mn‐Rich Region

AbstractThe deposition–dissolution mechanism with a two‐electron transfer reaction endows aqueous Zn–Mn batteries with a desirable theoretical energy density. However, due to the limited solubility of traditional manganese‐based materials and the competitive Mn shuttle behavior, the practical performance is unsatisfactory. Herein, by synergistically incorporating a novel Mn‐rich Mn4N cathode with a plasma functionalized carbon nanotubes film (PCNT) interlayer, an aqueous Zn–Mn battery with a high Mn‐utilization rate and high energy/power density is successfully developed. Specifically, the Mn4N cathode boasts high manganese content and dissolution activity, thereby offering a copious supply of Mn2+ ions for the battery system. The PCNT interlayer, with abundant micropore structures and functional groups, not only restrains the Mn2+ shuttle by entrapping the dissolved Mn2+ but also offers copious reaction sites, ensuring concentrating Mn2+ on the cathodic side and maximizing their contribution to the electrochemical reaction. Consequently, Mn4N‐PCNT exhibits a low polarization voltage and superior Mn‐utilization rate (64.8%). Without the MnSO4 additive, Mn4N‐PCNT achieves an ultra‐high energy density of 821.9 W h kg−1 and remarkable long‐term cycling stability (90% capacity retention over 9000 cycles). The delightful results demonstrate the practical application potential of Mn4N‐PCNT and open up new avenues for the rational design of advanced Zn–Mn batteries.

Study on the Catalytic Oxidation of Toluene Using CeO2@S-AZMB Prepared from Spent Zn-Mn Batteries

The recycling and utilization of waste alkaline zinc manganese batteries (S-AZMB) has always been a focus of attention in the fields of environment and energy. However, current research mostly focuses on the recycling of purified materials, while neglecting the direct reuse of waste batteries. Here, we propose a new concept of preparing thermal catalysts by combining unpurified S-AZMB with CeO2 by means of ball milling. A series of characterizations and experiments have confirmed that the combination with S-AZMB not only enhances the thermal catalytic activity of CeO2 but also significantly enhances the concentration of surface oxygen vacancies. In the toluene removal experiment, the temperature (T90) at 90% toluene conversions of CeO2@S-AZMB was 180 °C, lower than the 220 °C for CeO2. More noteworthy is that this S-AZMB-based thermal catalyst can maintain a good structure and thermal catalytic stability in cyclic catalysis.

ZnO Additive Boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn Batteries

HighlightsLow pH value of electrolyte suppresses the charge capabilities of electrolytic Zn–Mn batteries.Unique solid phase alkaline properties of zinc sulfate hydroxide hydrate endow the electrolytic Zn–Mn batteries with greatly enhanced charge capabilities.The highly active Zn2Mn3O8·H2O nanorods array deposited during the charge process improve the discharge efficiency and stability of electrolytic Zn–Mn batteries.

Rationally designed carbon-encapsulated manganese selenide composites from metal–organic frameworks for stable aqueous Zn–Mn batteries

Electrochemical kinetics unveiled enhanced surface pseudocapacitance in C@MnSe@GO-2, while ex situ XRD exposed the transformation mechanism during activation.

Molecularly modulating solvation structure and electrode interface enables dendrite-free zinc-ion batteries

The performance of aqueous Zn ion batteries (AZIBs) is hindered by the uncontrollable growth of Zn dendrites and side reactions at the Zn anode/electrolyte interface. Here, we introduce low-cost glucosamine hydrochloride (GLA) into the ZnSO4 electrolyte system to modulate the Zn anode/electrolyte interface and the solvation structure of Zn2+, which leads to improved reversibility of Zn plating/striping. Through experimental and theoretical analyses, we demonstrate that GLA molecules could adsorp on the Zn metal surface to form a new interface with reduced active water, effectively suppressing water-induced side reactions. Moreover, after adding GLA, the flux of Zn2+ ions is regulated, the desolvation of the primary [Zn(H2O)6]2+ ions is promoted, and the Zn dendrite growth is significantly inhibited. Consequently, superior cyclic stability with a lower voltage hysteresis is simultaneously achieved in a Zn//Zn symmetric cell. When coupled with the Mn3O4 cathode, the fabricated Zn-Mn batteries with the modified ZnSO4 + GLA electrolyte system deliver boosted capacity, improved long-term cycling stability, and better self-discharge performance. This work provides insight into the development of high-efficient and low-cost electrolytes for high-performance Zn-based energy storage devices.

An Organic Coordination Manganese Complex as Cathode for High-Voltage Aqueous Zinc-metal Battery.

Aqueous Zn-Mn battery has been considered as the most promising scalable energy-storage system due to its intrinsic safety and especially ultralow cost. However, the traditional Zn-Mn battery mainly using manganese oxides as cathode shows low voltage and suffers from dissolution/disproportionation of the cathode during cycling. Herein, for the first time, a high-voltage and long-cycle Zn-Mn battery based on a highly reversible organic coordination manganese complex cathode (Manganese polyacrylate, PAL-Mn) was constructed. Benefiting from the insoluble carboxylate ligand of PAL-Mn that can suppress shuttle effect and disproportionationation reaction of Mn3+ in a mild electrolyte, Mn3+ /Mn2+ reaction in coordination state is realized, which not only offers a high discharge voltage of 1.67 V but also exhibits excellent cyclability (100 % capacity retention, after 4000 cycles). High voltage reaction endows the Zn-Mn battery high specific energy (600 Wh kg-1 at 0.2 A g-1 ), indicating a bright application prospect. The strategy of introducing carboxylate ligands in Zn-Mn battery to harness high-voltage reaction of Mn3+ /Mn2+ well broadens the research of high-voltage Zn-Mn batteries under mild electrolyte conditions.

Nanomicellar Electrolyte To Control Release Ions and Reconstruct Hydrogen Bonding Network for Ultrastable High-Energy-Density Zn-Mn Battery.

Zn-Mn batteries with two-electron conversion reactions simultaneously on the cathode and anode harvest a high voltage plateau and high energy density. However, the zinc anode faces dendrite growth and parasitic side reactions while the Mn2+/MnO2 reaction on the cathode involves oxygen evolution and possesses poor reversibility. Herein, a novel nanomicellar electrolyte using methylurea (Mu) has been developed that can encapsulate ions in the nanodomain structure to guide the homogeneous deposition of Zn2+/Mn2+ in the form of controlled release under an external electric field. Consecutive hydrogen bonding network is broken and a favorable local hydrogen bonding system is established, thus inhibiting the water-splitting-derived side reactions. Concomitantly, the solid-electrolyte interface protective layer is in situ generated on the Zn anode, further circumventing the corrosion issue resulting from the penetration of water molecules. The reversibility of the Mn2+/MnO2 conversion reaction is also significantly enhanced by regulating interfacial wettability and improving nucleation kinetics. Accordingly, the modified electrolyte endows the symmetric Zn∥Zn cell with extended cyclic stability of 800 h with suppressed dendrites growth at an areal capacity of 1 mAh cm-2. The assembled Zn-Mn electrolytic battery also demonstrates an exceptional capacity retention of nearly 100% after 800 cycles and a superior energy density of 800 Wh kg-1 at an areal capacity of 0.5 mAh cm-2.

Amorphous Heterostructure Derived from Divalent Manganese Borate for Ultrastable and Ultrafast Aqueous Zinc Ion Storage.

Aqueous zinc-manganese (Zn-Mn) batteries have promising potential in large-scale energy storage applications since they are highly safe, environment-friendly, and low-cost. However, the practicality of Mn-based materials is plagued by their structural collapse and uncertain energy storage mechanism upon cycling. Herein, this work designs an amorphous manganese borate (a-MnBOx ) material via disordered coordination to alleviate the above issues and improve the electrochemical performance of Zn-Mn batteries. The unique physicochemical characteristic of a-MnBOx enables the inner a-MnBOx to serve as a robust framework in the initial energy storage process. Additionally, the amorphous manganese dioxide, amorphous Znx MnO(OH)2 , and Zn4 SO4 (OH)6 ·4H2 O active components form on the surface of a-MnBOx during the charge/discharge process. The detailed in situ/ex situ characterization demonstrates that the heterostructure of the inner a-MnBOx and surface multicomponent phases endows two energy storage modes (Zn2+ /H+ intercalation/deintercalation process and reversible conversion mechanism between the Znx MnO(OH)2 and Zn4 SO4 (OH)6 ·4H2 O) phases). Therefore, the obtained Zn//a-MnBOx battery exhibits a high specific capacity of 360.4 mAh g-1 , a high energy density of 484.2Wh kg-1 , and impressive cycling stability (97.0% capacity retention after 10000 cycles). This finding on a-MnBOx with a dual-energy storage mechanism provides new opportunities for developing high-performance aqueous Zn-Mn batteries.

Reunderstanding aqueous Zn electrochemistry from interfacial specific adsorption of solvation structures

Reunderstanding the faradaic reaction mechanism at the electrode/electrolyte interface from the specific adsorption of solvation structures towards advanced aqueous Zn–Mn batteries.

Phase-Transformation-Activated MnCO3 as Cathode Material of Aqueous Zinc-Ion Batteries

The intrinsic high safety of rechargeable aqueous batteries makes them particularly advantageous in the field of large-scale energy storage. Among them, rechargeable Zn–Mn batteries with high energy density, low cost, high discharge voltage, and nontoxicity have been considered as one of the most promising aqueous battery systems. However, exiting research on manganese-based cathode materials mainly focuses on diverse manganese oxides analogs, while reports on other promising manganese-based analogs with high performance are still limited. Herein, we report a MnCO3 cathode material, which can be manufactured on a large scale by a facile coprecipitation method. Interestingly, the MnCO3 can spontaneously be converted into MnO2 material during the charging process. The Zn–MnCO3 battery delivers a highly specific capacity (280 mAh g−1) even at the high current density of 50 mA g−1. It is also noteworthy that the battery with a high loading mass (7.2 mg cm−2) exhibits good reversibility of charge–discharge for 2000 cycles, showing a competitive cycling stability in aqueous systems.

Oxygen functionalized interface enables high MnO2 electrolysis kinetics for high energy aqueous Zn-MnO2 decoupled battery

Aqueous Zn-based batteries show great potential in large scale energy storage system due to their low-cost and high-safety merits. However, the practical application of Zn-based batteries is restricted by their inferior energy and power densities, which is resulted from the low output voltage and poor reaction kinetics of cathode materials. To address the above issues, we propose a decoupled aqueous Zn–Mn battery with high-rate and high-voltage by using oxygen functionalized carbon nanotubes (OCNTs) substrate. The functional interface can greatly improve the wettability of the electrode, promote the ion transport capability, and facilitate the rapid deposition/dissolution of MnO2/Mn2+. Consequently, the OCNTs/MnO2 electrode can deliver a high capacity of 9.2 mA h cm−2 and superior capacity retention of 86.6% at an ultrahigh current density of 200 mA cm−2. When coupled with Zn anode, the Zn//OCNTs/MnO2 decoupled full battery exhibits a high discharge plateau (∼2.45 V) and area specific capacity (1.96 mA h cm−2) at a current density of 2 mA cm−2. Moreover, the outstanding peak power density of 13.4 kW kg−1 and peak energy density of 564.4 W h kg−1 can be achieved for Zn//OCNTs/MnO2 battery (based on the mass of active material involved in the reaction on the positive and negative electrodes during charge and discharge), far beyond currently reported aqueous electrochemical energy storage devices. This work provides a train of thoughts for the development of high energy and power density aqueous batteries.

A novel S-scheme heterojunction in spent battery-derived ZnFe2O4/g-C3N4 photocatalyst for enhancing peroxymonosulfate activation and visible light degradation of organic pollutant

Waste resource recovery and water pollution control are two important issues in environmental protection. In this study, ZnFe2O4 prepared from spent alkaline Zn-Mn battery was combined with g-C3N4 (CN) to form ZnFe2O4/g-C3N4 (ZFO-CN) step-scheme (S-scheme) heterojunction photocatalyst to eliminate bisphenol A (BPA) in the presence of peroxymonosulfate (PMS) under visible light (Vis, λ ≥ 400 nm). Results revealed that the ZFO-CN possessed an outstanding photocatalytic performance, which was attributed to the superior visible light harvest capacity and unique S-scheme charge transfer pathway as evidenced by X-ray photoelectron spectroscopy and electrochemical test. Reactive species including SO4•−, •OH, •O2−, 1O2 and h+ co-existed in the system, among which the non-radicals including 1O2 and h+ were inferred to be the predominant oxidation species based on the result of chemical quenching experiments. The effects of catalyst dosage, PMS concentration, initial pH and inorganic ion (HCO3−, Cl−, H2PO4−, NO3− or NH4+) on BPA removal were investigated. At 0.3 g L−1 ZFO-CN-0.5, 0.5 mM PMS and 60 min reaction time, more than 97.7% BPA was decomposed under visible light irradiation over a wide pH range of 3.5–9.0. This work provides a promising approach of constructing spent battery-derived spinel oxides into a high-efficiency heterojunction photocatalyst to activate PMS for practical wastewater treatment.

A composite photocatalytic system based on spent alkaline Zn–Mn batteries for toluene removal under multiple conditions

The resource utilization of spent alkaline Zn–Mn batteries (S-AZMB) has always been a hot issue in the field of energy regeneration and environmental protection. The cumbersome and complicated purification process is the reason for their limited recycling. Not long ago, we proved that unpurified S-AZMB can be used directly: construct a Z-scheme photocatalytic system by combining with commercial TiO2 through high-temperature calcination. In order for this finding to be truly adopted by the application market, the high energy consumption calcination process needs to be improved urgently. In this work, we explore the temperature dependence of performance for the composite photocatalyst (TiO2@S-AZMB). A series of experimental results confirm that lowering the calcination temperature not only conducive to improving the separation efficiency of photogenerated electron-hole pairs, but also can significantly improve the environmental adaptability of the catalyst. Specifically, the catalyst synthesized by calcination temperature at 200 °C exhibits higher toluene removal efficiency than that at 500 °C under different initial concentration of pollutants, relative humidity, light intensity and oxygen content. This study not only further improves the photocatalytic performance of the composite catalyst, but also accords with the idea of energy saving and emission reduction, which provides more space for the possibility of recycling S-AZMB.

Utilizing waste Zn-Mn batteries in combination with waste SCR catalyst to construct a magnetically recoverable and highly photocatalytic materials

The ZMF@S10 composite that was synthesized by using spent Zn-Mn batteries and abandon SCR catalyst as the starting materials for magnetic photocatalysts with high photocatalytic activity is successfully prepared in this study. The results showed that the core TiO2 crystal structure will transform from anatase to rutile, which was then covered in the ZMF. The efficient photocatalytic performance of the composites under visible light is due to the inhibition of the recombination rate of photogenerated dots and holes on the surface of ZMF by the presence of rutile TiO2. Besides, all composites show good stability, regeneration performance, and easy recycling.

Reunderstanding the Reaction Mechanism of Aqueous Zn-Mn Batteries with Sulfate Electrolytes: Role of the Zinc Sulfate Hydroxide.

Rechargeable aqueous Zn-Mn batteries have garnered extensive attention for next-generation high-safety energy storage. However, the charge-storage chemistry of Zn-Mn batteries remains controversial. Prevailing mechanisms include conversion reaction and cation (de)intercalation in mild acid or neutral electrolytes, and a MnO2 /Mn2+ dissolution-deposition reaction in strong acidic electrolytes. Herein, a Zn4 SO4 ·(OH)6 ·xH2 O (ZSH)-assisted deposition-dissolution model is proposed to elucidate the reaction mechanism and capacity origin in Zn-Mn batteries based on mild acidic sulfate electrolytes. In this new model, the reversible capacity originates from a reversible conversion reaction between ZSH and Znx MnO(OH)2 nanosheets in which the MnO2 initiates the formation of ZSH but contributes negligibly to the apparent capacity. The role of ZSH in this new model is confirmed by a series of operando characterizations and by constructing Zn batteries using other cathode materials (including ZSH, ZnO, MgO, and CaO). This research may refresh the understanding of the most promising Zn-Mn batteries and guide the design of high-capacity aqueous Zn batteries.

Removal of Zn(II) and Mn(II) by Ion Flotation from Aqueous Solutions Derived from Zn-C and Zn-Mn(II) Batteries Leaching

The Zn(II) and Mn(II) removal by an ion flotation process from model and real dilute aqueous solutions derived from waste batteries was studied in this work. The research aimed to determine optimal conditions for the removal of Zn(II) and Mn(II) from aqueous solutions after acidic leaching of Zn-C and Zn-Mn waste batteries. The ion flotation process was carried out at ambient temperature and atmospheric pressure. Two organic compounds used as collectors were applied, i.e., m-dodecylphosphoric acid 32 and m-tetradecylphosphoric 33 acid in the presence of a non-ionic foaming agent (Triton X-100, 29). It was found that both compounds can be used as collectors in the ion flotation for Zn(II) and Mn(II) removal process. Process parameters for Zn(II) and Mn(II) flotation have been established for collective or selective removal metals, e.g., good selectivity coefficients equal to 29.2 for Zn(II) over Mn(II) was achieved for a 10 min process using collector 32 in the presence of foaming agent 29 at pH = 9.0.

A high-voltage rechargeable alkaline Zn–MnO4− battery with enhanced stability achieved by highly reversible MnO4−/MnO42− redox pair

Development of rechargeable alkaline Zn–Mn batteries has been facing big challenges for low working voltage and poor cycling stability, although they have advantages of low cost, high safety, and simple maintenance. For the first time, this work demonstrates a record high voltage (1.78 V) for rechargeable alkaline Zn–MnO4− battery achieved by a high reversible redox pair of MnO4−/MnO42−, which shows excellent cycling stability up to 1,500 cycles at a high current density of 20 mA cm−2 without obvious capacity attenuation. The MnO4−/MnO42− redox reaction investigated by ex-situ scanning electron microscope as well as ultraviolet and visible absorption spectrum indicates high reversibility of the MnO4−/MnO42− redox couple after the activation during the first discharge process. Furthermore, benefiting from the liquid-phase reaction nature of MnO4−/MnO42−, a flow battery is further prototyped to show highly stable cycles with 95.8% of discharge capacity retention for 600 cycles at the current density of 40 mA cm−2.