Zinc-air Research Articles

An Efficient Cathode Catalyst for Rechargeable Zinc-air Batteries based on the Derivatives of MXene@ZIFs.

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are crucial processes at the cathode of zinc-air batteries. Developing highly efficient and durable electrocatalysts at the air cathode is significant for the practical application of rechargeable zinc-air batteries. Herein, N-doped layered MX containing Co2P/Ni2P nanoparticles is synthesized by growing CoNi-ZIF on the surface and interlayers of the two-dimensional material MXene (Ti2C3) followed by phosphating calcination. The growth of CoNi-ZIF on the surface of MXene results in the attenuation of high-temperature structural damage of MXene, which in turn leads to the formation of Co2P/Ni2P@MX with a hierarchical configuration, higher electron conductivity, and abundant active sites. The optimized Co2P/Ni2P@MX achieves a half-wave potential of 0.85 V for the ORR and an overpotential of 345 mV for the OER. In addition, DFT calculations were adopted to investigate the mechanism at the atomic and molecular levels. The liquid zinc-air battery with Co2P/Ni2P@MX as the cathode exhibits a specific capacity of 783.7 mAh g-1 and exceeds 280 h (840 cycles) cycle stability, superior to zinc-air batteries constructed by the cathode of commercial Pt/C+RuO2 and other previous works. Furthermore, a solid-state battery synthesized with Co2P/Ni2P@MX as the cathode exhibits stable cycle performance (154 h/462 cycles).

Tailored Self-Supported Co,Ni/MnO2 Nanorods@Hierarchical Carbon Spheres Chains as Advanced Electrocatalysts for Rechargeable Zn-Air battery and Self-Driven Water Splitting

Tailored Self-Supported Co,Ni/MnO₂ Nanorods@Hierarchical Carbon Spheres Chains as Advanced Electrocatalysts for Rechargeable Zn-Air battery and Self-Driven Water Splitting

High-Entropy Prussian Blue Analogue Derived Heterostructure Nanoparticles as Bifunctional Oxygen Conversion Electrocatalysts for the Rechargeable Zinc-Air Battery.

In response to energy challenges, rechargeable zinc-air batteries (RZABs) serve as an ideal platform for energy storage with a high energy density and safety. Nevertheless, addressing the sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in RZAB requires highly active and robust electrocatalysts. High-entropy Prussian blue analogues (HEPBAs), formed by mixing diverse metals within a single lattice, exhibit enhanced stability due to their increased mixing entropy, which lowers the Gibbs free energy. HEPBAs innately enable sacrificial templating, an effective way to synthesize complex structures. Impressively, in this study, we successfully transform HEPBAs into exquisite multiphase (multimetallic alloy, metal carbide, and metal oxide) heterostructure nanoparticles through a controlled synthesis process. The elusive multiphase heterostructure nanoparticles manifested two active sites for selective ORR and OER. By integrating CNT into HEPBA-derived nanoparticles (HEPBA/CNT-800), the HEPBA/CNT-800 demonstrates superior activity toward both ORR (E1/2 = 0.77 V) in a 0.1 M KOH solution and the OER (η = 330 mV at 50 mA cm-2) in a 1 M KOH solution. The RZAB with a HEPBA/CNT-based air electrode demonstrated an open-circuit voltage of 1.39 V and provided a significant energy density of 71 mW cm-2. Moreover, the charge and discharge cycles lasting up to 40 h at a current density of 5 mA cm-2 demonstrate its excellent stability. This work provides an alternative avenue for the rational design of HEPBA's derivative for a sustainable rechargeable metal-air battery platform.

I3--Mediated Oxygen Evolution Activities to Boost Rechargeable Zinc-Air Battery Performance with Low Charging Voltage and Long Cycling Life.

An effective strategy to facilitate oxygen redox chemistry in metal-air batteries is to introduce a redox mediator into the liquid electrolyte. The rational utilization of redox mediators to accelerate the charging kinetics while ensuring the long lifetime of alkaline Zn-air batteries is challenging. Here, we apply commercial acetylene black catalysts to achieve an I3--mediated Zn-air battery by using ZnI2 additives that provide I3- to accelerate the cathodic redox chemistry and regulate the uniform deposition of Zn2+ on the anode. The Zn-air battery performs an ultra-long cycle life of over 600 h at 5 mA cm-2 with a final charge voltage of 1.87 V. We demonstrate that I- mainly generates I3- on the surface of carbon catalysts during the electrochemically charging process, which can further chemically react with OH- to generate oxygen and further revert to I-, thus obtaining a stable electrochemical system. This work offers a strategy to simultaneously improve the cycling life and reduce the charging voltage of Zn-air batteries through redox mediator methods.

Deep Eutectic Solvent and Molten Salt-Assisted Construction of Wheat Straw-Derived N/O Co-Doped Porous Carbon for Flexible Zinc-Air Batteries.

As a common biomass resource, wheat straw is gradually being derived as carbon materials for oxygen reduction reaction (ORR) in zinc-air batteries (ZABs). Herein, the wheat straw-derived carbon was prepared by ball milling and pyrolysis using deep eutectic solvent (DES) as the medium, which avoided the cumbersome procedures. The hydrogen bond of DES was utilized to reconstructed into a hydrogen bond network structure between DES and lignin/cellulose/hemicellulose of wheat straw. The hydrogen bond network structure was converted into N/O co-doped porous carbon (N/O-WSPC) with abundant N/O co-doped sites after high-temperature pyrolysis. Meanwhile, KHCO3 was employed to further generate hierarchical pore structures and increase the specific surface area of the N/O-WSPC. The N/O co-doped sites provided intrinsic ORR activity, while the porous structure facilitates the mass transfer effect. Therefore, the N/O-WSPC exhibited a half-wave potential of 0.87 V (vs. RHE) and a limiting current density of 5.98 mA cm-2 for ORR. The N/O-WSPC-based flexible ZAB displayed an energy density of 652.23 Wh kg-1 and a charging-discharging cycle duration for over 19 h. The DES-assisted strategy facilitates the sustainable and efficient application of wheat straw-derived carbon materials in energy storage and conversion devices.

Pd-Co₃O₄/Acetylene Black Nanocomposite as an Efficient and Robust Bifunctional ORR/OER Electrocatalyst for Rechargeable Zinc-Air Batteries

Developing cost-effective and high-performing bifunctional electrocatalysts is pivotal for advancing rechargeable zinc-air batteries (ZABs). In this study, a Pd-Co₃O₄ loaded on acetylene black (Pd-Co₃O₄/C) electrocatalyst was developed with excellent properties for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) using reduced H₂PdCl₄ to modify Co₃O₄/C. The experimental findings indicate that the Pd-Co₃O₄/C electrocatalyst exhibits a favorable half-wave potential for ORR at 0.91 V, a feasible potential for OER at 1.48 V (measured at 10 mA/cm2), also minor Tafel slopes for both ORR (44.65 mV/dec) and OER (58.41 mV/dec). Additionally, it evidences a power density of 186 mW/cm2 in ZABs and good durability during galvanostatic charge-discharge cycling. The impressive performance of Pd-Co₃O₄/C can be ascribed primarily to the beneficial synergistic effect resulting from the composition of Co₃O₄ and Pd embedded within graphite carbon. This research lays the groundwork for the expansion of additional cost-effective and highly effective electrocatalysts in the coming years.

Amorphous CoFePOx hollow nanocubes decorated with g-C3N4 quantum dots to achieve efficient electrocatalytic performance in the oxygen evolution reaction.

Simultaneously enriching active sites and enhancing intrinsic activity in a simple way is of great importance for the design of highly active electrocatalysts for the oxygen evolution reaction (OER), but it still faces challenges. Herein, g-C3N4 quantum dot decorated amorphous hollow CoFe bimetallic phosphate nanocubes (a-CoFePOx@CNQD) are prepared as an efficient OER electrocatalyst by a simple in situ etching-phosphating process. Research shows that their unique hollow architecture and amorphous structure can help provide generous exposed active sites for OER, and the incorporation of g-C3N4 quantum dots can effectively adjust the electronic structure to improve the intrinsic activity. Therefore, a-CoFePOx@CNQD exhibits excellent OER performance with a low overpotential (239 mV) at 10 mA cm-2 and a small Tafel slope (58.4 mV dec-1), surpassing the commercial RuO2. Furthermore, a-CoFePOx@CNQD as an electrode catalyst for a water electrolyzer and zinc-air battery also shows higher performance and stability than RuO2 + Pt/C catalysts. This study provides a feasible strategy for preparing efficient and stable amorphous hollow heterostructure OER electrocatalysts.

Fe3Co nanoparticles embedded carbon nanotube complex as effective bifunctional electrocatalysts for rechargeable zinc-air batteries

Fe3Co nanoparticles embedded carbon nanotube complex as effective bifunctional electrocatalysts for rechargeable zinc-air batteries

Heterointerfacial engineering of N,P-doped carbon nanosheets supported Co/Co2P nanoparticles for boosting oxygen reduction and oxygen evolution reactions towards rechargeable Zn-air battery

Heterointerfacial engineering of N,P-doped carbon nanosheets supported Co/Co2P nanoparticles for boosting oxygen reduction and oxygen evolution reactions towards rechargeable Zn-air battery

Effect of plant extract additives on the parasitic reaction in alkaline Zn-air batteries

Effect of plant extract additives on the parasitic reaction in alkaline Zn-air batteries

In-situ nitrogen-doped carbon nanotube-encapsulated Co9S8 nanoparticles as self-supporting bifunctional air electrodes for zinc-air batteries

In-situ nitrogen-doped carbon nanotube-encapsulated Co9S8 nanoparticles as self-supporting bifunctional air electrodes for zinc-air batteries

Enhanced bifunctional electrocatalysis of Co5.47N nanocrystals in porous carbon nanofibers for high-efficiency zinc-air batteries

Enhanced bifunctional electrocatalysis of Co5.47N nanocrystals in porous carbon nanofibers for high-efficiency zinc-air batteries

A Rechargeable Urea‐Assisted Zn‐Air Battery With High Energy Efficiency and Fast‐Charging Enabled by Engineering High‐Energy Interfacial Structures

AbstractElectrochemical urea oxidation reaction (UOR) offers a promising alternative to the oxygen evolution reaction (OER) in clean energy conversion and storage systems. Nickel‐based catalysts are regarded as highly promising electrocatalysts for the UOR. However, their effectiveness is significantly hindered by the unavoidable self‐oxidation reaction of nickel species during UOR. To address this challenge, we proposed an interface chemistry modulation strategy to boost UOR kinetics by creating a high‐energy interfacial heterostructure. This heterostructure incorporates Ag at the CoOOH@NiOOH heterojunction interface, where strong interactions significantly promote the electron exchanges at the heterojunction interface between ‐OH and ‐O groups. Consequently, the improved electron delocalization leads to the formation of stronger bonds between Co sites and urea CO(NH2)2, promoting a preference for urea to occupy Co active sites over OH*. The resulting catalyst, Ag−CoOOH@NiOOH, demonstrates ultrahigh UOR activity with a low potential of 1.33 V at 100 mA cm−2. The fabricated catalyst exhibits a mass activity over 11.9 times greater than the initial cobalt oxyhydroxide. The rechargeable urea‐assisted zinc‐air batteries (ZABs) achieve a record‐breaking energy efficiency of 74.56 % at 1 mA cm−2, remarkable durability (1000 hours at a current density of 50 mA cm−2), and quick charge performances.

A Rechargeable Urea-Assisted Zn-Air Battery With High Energy Efficiency and Fast-Charging Enabled by Engineering High-Energy Interfacial Structures.

Electrochemical urea oxidation reaction (UOR) offers a promising alternative to the oxygen evolution reaction (OER) in clean energy conversion and storage systems. Nickel-based catalysts are regarded as highly promising electrocatalysts for the UOR. However, their effectiveness is significantly hindered by the unavoidable self-oxidation reaction of nickel species during UOR. To address this challenge, we proposed an interface chemistry modulation strategy to boost UOR kinetics by creating a high-energy interfacial heterostructure. This heterostructure incorporates Ag at the CoOOH@NiOOH heterojunction interface, where strong interactions significantly promote the electron exchanges at the heterojunction interface between -OH and -O groups. Consequently, the improved electron delocalization leads to the formation of stronger bonds between Co sites and urea CO(NH2)2, promoting a preference for urea to occupy Co active sites over OH*. The resulting catalyst, Ag-CoOOH@NiOOH, demonstrates ultrahigh UOR activity with a low potential of 1.33 V at 100 mA cm-2. The fabricated catalyst exhibits a mass activity over 11.9 times greater than the initial cobalt oxyhydroxide. The rechargeable urea-assisted zinc-air batteries (ZABs) achieve a record-breaking energy efficiency of 74.56 % at 1 mA cm-2, remarkable durability (1000 hours at a current density of 50 mA cm-2), and quick charge performances.

Co/Co9S8 Nanofibers Decorated with Carbon Nanotubes as Oxygen Electrocatalysts for Zn–Air Batteries

Co/Co₉S₈ Nanofibers Decorated with Carbon Nanotubes as Oxygen Electrocatalysts for Zn–Air Batteries

Rigid Ligand Confined Synthesis of Carbon Supported Dimeric Fe Sites with High-Performance Oxygen Reduction Reaction Activity for Quasi-Solid-State Rechargeable Zn-Air Batteries.

Dimeric metal sites (DiMSs) in carbon-based single atom catalysts (SACs) offer distinct advantages in optimizing the adsorption energies of the catalytic intermediates and reaction pathways over single atom sites, which inspires the investigations on the rational design of DiMSs-based SACs and the accurate discernment of catalytic mechanisms. Here, dimeric Fe sites on carbon blacks (DiFe-N/CBs) are prepared using the precursor of metal-organic complex with a controlled structure, and the rigid ligand confinement secures the preservation of dimeric Fe sites during the thermal treatment. DiFe-N/CBs shows excellent electrocatalytic performance for oxygen reduction reaction (ORR) with a high half-wave potential of 0.917 V, and excellent durability with negligible activity decay. Theoretical studies reveal that the dimeric Fe sites have an optimal adsorption of OOH* with the Yeager-type binding, illustrating the advantages of DiMSs over SAs in catalyzing ORR. The rechargeable aqueous and quasi-solid-state Zn-air batteries assembled using DiFe-N/CBs-based air cathodes achieve small voltage gaps after long term charge/discharge test, showing great promises for practical applications. This synthetic strategy serves a novel platform to produce a scope of catalysts incorporating multimeric metal sites, and studies on the catalytic mechanism lay the foundation for establishing cooperative effect for multidentate adsorption reactions.

MOF-derived CoCu-N-doped porous carbon frame electrocatalyst for high performance zinc-air battery

MOF-derived CoCu-N-doped porous carbon frame electrocatalyst for high performance zinc-air battery

Recent Advances in Engineering Fe-N-C Catalysts for Oxygen Electrocatalysis in Zn-Air Batteries.

Fe-N-C single-atom catalysts (SACs) have emerged as one of the most promising candidates for oxygen electrocatalysis due to their maximized atom utilization efficiency, high intrinsic activity, and strong metal-support interaction. Significant progress has been made in engineering Fe-N-C SACs for oxygen electrocatalysis in Zn-air batteries (ZABs). This review provides a comprehensive overview of the recent advancements in Fe-N-C SACs, with a special focus on effective engineering strategies, their performance in oxygen electrocatalysis, and their potential applications in ZABs. The review also discusses the key challenges and future directions in the development of Fe-N-C SACs for efficient and durable oxygen electrocatalysis in ZABs. This review aims to offer valuable insights into the current state of research in this field and to guide future efforts in the development of advanced oxygen electrocatalysts for ZABs.

Prussian Blue-Derived Atomic Fe/Fe3C@N-Doped C Catalysts Supported by Carbon Cloth as Integrated Air Cathode for Flexible Zn-Air Batteries.

The development of an integrated air cathode with superior oxygen reduction reaction (ORR) performance is fundamental to flexible zinc-air batteries (ZABs) for wearable electronics. Herein, a self-assembled metal-organic framework (MOF)-derived strategy is proposed to prepare a atomic Fe/Fe3C@N-doped C catalysts supported by carbon cloth (CC) catalyst for use as an air cathode of flexible ZABs. The Prussian Blue precursor, which self-assembles on the surface of the carbon cloth due to electrostatic attraction, is critical in achieving the uniform dispersion of catalysts with high density loading on carbon cloth substrates. The hollow cubic structure, N-doped carbon layer coating, and the integrated electrode design can provide more accessible active sites and facilitate a rapid electron transfer and mass transport. Density functional theory (DFT) calculation reveals that the electronic interactions between the Fe-N4 and Fe3C dual active sites can optimize the adsorption-desorption behavior of oxygen intermediates formed during the ORR. Consequently, the Fe/Fe3C@N-doped C/CC exhibits an excellent half wave potential (E1/2 = 0.903V) and superior long-term cycling stability in alkaline environments. With excellent ORR performance, ZABs and flexible ZABs based on Fe/Fe3C@N-doped C/CC air cathode demonstrate excellent overall electrochemical performance in terms of open circuit voltage, maximum power density, flexibility, and cycling stability.

Microwave‐assisted control of PtNi nanoalloy clusters on the nitrogen‐doped graphene oxide for energy conversion with oxygen reduction reaction and hydrogen evolution reaction

AbstractResearch on the production and utilization of hydrogen energy is essential to overcome the environmental issues caused by fossil fuels. Herein, we anchor PtNi nanoalloy clusters (Pt‐Ni NACs) on nitrogen‐doped graphene oxide (NrGO) by a facile microwave‐assisted synthesis and analyze the variations of catalyst properties based on the PtNi composition and the presence of nitrogen. Ni inclusion in the Pt matrix can induce lattice strain and change the electronic structure, while the doped nitrogen into the graphene can enhance electron transfer and improve the durability of the catalyst through strong chemical bonding with the alloy clusters. TEM analysis discovers that the NACs are uniformly decorated in a few‐nanometer‐size on the graphene surface, and the formation of the PtNi NACs and structural changes according to composition are confirmed through XRD and XPS. In addition, the structural changes due to N‐doping and its bonding with the NACs are observed through Raman spectroscopy and XPS. Electrochemical measurements reveal that Pt2.6Ni NACs/NrGO exhibits the highest ORR onset potential (0.893 V) and the lowest HER overpotential at 10 mA cm−2 (22 mV) among other catalysts, and those activities are almost unchanged under long‐term durability tests. From these results, Pt2.6Ni NACs/NrGO is utilized in a zinc‐air battery (ZAB) system, demonstrating better battery performance than commercial Pt and Ir‐based catalysts. Moreover, it is applied to hydrogen collection, showing linear trend in hydrogen production over time, confirming the catalyst's availability in hydrogen production and utilization.image