Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,a...Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,achieving high energy density in Zn||MnO_(2)batteries remains challenging,highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components,including electrodes and electrolytes.This review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO_(2)batteries in mildly and strongly acidic environments.Furthermore,we highlight the key challenges hindering the extensive application of Zn||MnO_(2)batteries,including high-voltage requirements and areal capacity,and propose innovative solutions to overcome these challenges.We suggest that MnO_(2)/Mn^(2+)conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO_(2)batteries.These approaches could lead to breakthroughs in the future development of Zn||MnO_(2)batteries,off ering a more sustainable,costeff ective,and high-performance alternative to traditional batteries.展开更多
Manganese-based cathode materials are considered as a promising candidate for rechargeable aqueous zinc-ion batteries(ZIBs).Suffering from poor conductive and limited structure tolerance,various carbon matrix,especial...Manganese-based cathode materials are considered as a promising candidate for rechargeable aqueous zinc-ion batteries(ZIBs).Suffering from poor conductive and limited structure tolerance,various carbon matrix,especially N-doped carbon,were employed to incorporate with MnO_(2)for greatly promoted electrochemical performances.However,the related underlying mechanism is still unknown,which is unfavorable to guide the design of high performance electrode.Herein,by incorporating layered MnO_(2)with N-doped carbon nanowires,a free-standing cathode with hierarchical core-shell structure(denoted as MnO_(2)@NC)is prepared.Benefiting from the N-doped carbon and rational architecture,the MnO_(2)@NC electrode shows an enhanced specific capacity(325 mAh g^(−1)at 0.1 A g^(−1))and rate performance(90 mAh g^(−1)at 2 A g^(−1)),as well as improved cycling stability.Furthermore,the performance improvement mechanism of MnO_(2)incorporated by N-doped carbon is investigated by X-ray photoelectron spectroscopy(XPS),Raman spectrums and density functional theory(DFT)calculation.The N atom elongates the Mn-O bond and reduces the valence of Mn^(4+)ion in MnO_(2)crystal by delocalizing its electron clouds.Thus,the electrostatic repulsion will be weakened when Zn^(2+)/H^(+)insert into the host MnO_(2)lattices,which is profitable to more cation insertion and faster ion transfer kinetics for higher capacity and rate capability.This work elucidates a fundamental understanding of the functions of N-doped carbon in composite materials and shed light on a practical pathway to optimize other electrode materials.展开更多
In this study electrochemical performance of Al and some of its alloys (Al-Zn, Al-rvlg and Al-rvln) anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the b...In this study electrochemical performance of Al and some of its alloys (Al-Zn, Al-rvlg and Al-rvln) anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn〉Al-Mg〉Al〉Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy (SEM). SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure. Electrolytic manganese dioxide (EMD) produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore (β-MnO2) by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample (EMD1) was performed well in comparison with EMD standard (EMD2) (commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S). SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.展开更多
Aqueous rechargeable Zn//MnO_(2)batteries have been considered as the promising candidate for future energy storage system due to their economic and environmental merits.However,the high-performance Zn//MnO_(2)batteri...Aqueous rechargeable Zn//MnO_(2)batteries have been considered as the promising candidate for future energy storage system due to their economic and environmental merits.However,the high-performance Zn//MnO_(2)batteries are plagued by poor sluggish reaction kinetics and capacity degradation due to the strong electrostatic interactions and complicated reaction process.Herein,the synergistic effect of atom defects engineering and phase transformation mechanism is confirmed as the effective strategy to enhance ion/charge transfer kinetics and structural stability.Defects gradient controlling and electrochemically induced phase transformation from spinel to layered structure render the aqueous Zn//λ-MnO_(2)system delivers a high discharge capacity of 285 m Ah/g and capacity retention of 81%after 500 cycles.展开更多
Aqueous rechargeable Zn//MnO_(2)batteries show promising prospects for grid-scale energy storage due to their intrinsic safety,abundant resource,and potential high performance.Unfortunately,the real capability of thes...Aqueous rechargeable Zn//MnO_(2)batteries show promising prospects for grid-scale energy storage due to their intrinsic safety,abundant resource,and potential high performance.Unfortunately,the real capability of these devices is far from satisfactory thanks to the low capacity and sluggish kinetics of the MnO_(2)cathode.Herein,we report a dual cation doping strategy by synthesis of MnO_(2)in the presence of Ti_(3)_(2)X MXenes and Ni^(2+)ions to essentially address these drawbacks.Such a process contributes to a Ti,Ni co-dopedα-MnO_(2)anchored on MXenes.The Ti^(3+)ions incorporated in the framework allow a partial multivalent variation for a large capacity while the Ni^(2+)ions promote the H^(+)transfer within the MnO_(2)matrix via the Grotthuss proton transport manner.As a result,the optimal dual cation doped MnO_(2)exhibits a large reversible capacity of 378 mAh·g-1 at 0.1 C and a high rate capability.Moreover,capacity retention as high as 92%is observed after cycling at 4 C for 1000 times,far superior to many of the previously reported results.This facile strategy demonstrated here may shed new insight into the rational design of electrodes based on high-performance Zn//MnO_(2)batteries.展开更多
The key challenges in aqueous zinc-manganese dioxide batteries(MnO_(2)//Zn)are their poor electrochemical kinetics and stability,which are mainly due to low conductivity and the inevitable dissolution of MnO_(2).A syn...The key challenges in aqueous zinc-manganese dioxide batteries(MnO_(2)//Zn)are their poor electrochemical kinetics and stability,which are mainly due to low conductivity and the inevitable dissolution of MnO_(2).A syn-ergistic combination of a Co-doped𝜎σ-MnO_(2)electrode(Co-MnO_(2))and a Co(CH_(3)COO)_(2)•4H_(2)O(CoAc)electrolyte additive is here developed to design a high-performance aqueous MnO_(2)//Zn battery(denoted as a Co-MnO_(2)//Zn battery with CoAc).The introduction of Co ions(Co^(3+)/Co^(2+))into the𝜎σ-MnO_(2)electrode is achieved via a facile one-step electrodeposition method.Benefitting from the synergistic coupling effect of the Co-MnO_(2)electrode and the CoAc electrolyte additive,the fabricated Co-MnO_(2)//Zn battery with CoAc shows a commendable dis-charge capacity of 313.8 mAh g^(−1)at 0.5 A g^(−1),excellent rate performance,excellent durability over 1000 cycles(∼92%capacity retention at 1.0 A g^(−1))and admirable energy density(439.3 Wh kg^(−1)),which is a significant improvement compared with an un-doped𝜎σ-MnO_(2)//Zn battery.展开更多
文摘Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,achieving high energy density in Zn||MnO_(2)batteries remains challenging,highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components,including electrodes and electrolytes.This review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO_(2)batteries in mildly and strongly acidic environments.Furthermore,we highlight the key challenges hindering the extensive application of Zn||MnO_(2)batteries,including high-voltage requirements and areal capacity,and propose innovative solutions to overcome these challenges.We suggest that MnO_(2)/Mn^(2+)conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO_(2)batteries.These approaches could lead to breakthroughs in the future development of Zn||MnO_(2)batteries,off ering a more sustainable,costeff ective,and high-performance alternative to traditional batteries.
基金supported by National Natural Science Foundation of China(Nos.U20A20246,51872108)the Fundamental Research Funds for the Central Universities(Nos.30106200463 and CCNU20TS006)Graduate Education Innovation Grant from Central China Normal University(No.2020CXZZ101).
文摘Manganese-based cathode materials are considered as a promising candidate for rechargeable aqueous zinc-ion batteries(ZIBs).Suffering from poor conductive and limited structure tolerance,various carbon matrix,especially N-doped carbon,were employed to incorporate with MnO_(2)for greatly promoted electrochemical performances.However,the related underlying mechanism is still unknown,which is unfavorable to guide the design of high performance electrode.Herein,by incorporating layered MnO_(2)with N-doped carbon nanowires,a free-standing cathode with hierarchical core-shell structure(denoted as MnO_(2)@NC)is prepared.Benefiting from the N-doped carbon and rational architecture,the MnO_(2)@NC electrode shows an enhanced specific capacity(325 mAh g^(−1)at 0.1 A g^(−1))and rate performance(90 mAh g^(−1)at 2 A g^(−1)),as well as improved cycling stability.Furthermore,the performance improvement mechanism of MnO_(2)incorporated by N-doped carbon is investigated by X-ray photoelectron spectroscopy(XPS),Raman spectrums and density functional theory(DFT)calculation.The N atom elongates the Mn-O bond and reduces the valence of Mn^(4+)ion in MnO_(2)crystal by delocalizing its electron clouds.Thus,the electrostatic repulsion will be weakened when Zn^(2+)/H^(+)insert into the host MnO_(2)lattices,which is profitable to more cation insertion and faster ion transfer kinetics for higher capacity and rate capability.This work elucidates a fundamental understanding of the functions of N-doped carbon in composite materials and shed light on a practical pathway to optimize other electrode materials.
文摘In this study electrochemical performance of Al and some of its alloys (Al-Zn, Al-rvlg and Al-rvln) anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn〉Al-Mg〉Al〉Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy (SEM). SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure. Electrolytic manganese dioxide (EMD) produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore (β-MnO2) by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample (EMD1) was performed well in comparison with EMD standard (EMD2) (commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S). SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.
基金supported by the National Natural Science Foundation of China (Nos. 52172263, 51932011)the Hunan Outstanding Youth Talents (No. 2021JJ10064)+2 种基金the Program of Youth Talent Support for Hunan Province (No. 2020RC3011)the InnovationDriven Project of Central South University (No. 2020CX024)the Fundamental Research Funds for the Central Universities of Central South University (No. 202321024)。
文摘Aqueous rechargeable Zn//MnO_(2)batteries have been considered as the promising candidate for future energy storage system due to their economic and environmental merits.However,the high-performance Zn//MnO_(2)batteries are plagued by poor sluggish reaction kinetics and capacity degradation due to the strong electrostatic interactions and complicated reaction process.Herein,the synergistic effect of atom defects engineering and phase transformation mechanism is confirmed as the effective strategy to enhance ion/charge transfer kinetics and structural stability.Defects gradient controlling and electrochemically induced phase transformation from spinel to layered structure render the aqueous Zn//λ-MnO_(2)system delivers a high discharge capacity of 285 m Ah/g and capacity retention of 81%after 500 cycles.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21975258,22179145,22005341,and 21878336)the startup support grant from China University of Petroleum(East China)Shandong Provincial Natural Science Foundation(Nos.ZR2020ZD08 and ZR2018ZC1458).
文摘Aqueous rechargeable Zn//MnO_(2)batteries show promising prospects for grid-scale energy storage due to their intrinsic safety,abundant resource,and potential high performance.Unfortunately,the real capability of these devices is far from satisfactory thanks to the low capacity and sluggish kinetics of the MnO_(2)cathode.Herein,we report a dual cation doping strategy by synthesis of MnO_(2)in the presence of Ti_(3)_(2)X MXenes and Ni^(2+)ions to essentially address these drawbacks.Such a process contributes to a Ti,Ni co-dopedα-MnO_(2)anchored on MXenes.The Ti^(3+)ions incorporated in the framework allow a partial multivalent variation for a large capacity while the Ni^(2+)ions promote the H^(+)transfer within the MnO_(2)matrix via the Grotthuss proton transport manner.As a result,the optimal dual cation doped MnO_(2)exhibits a large reversible capacity of 378 mAh·g-1 at 0.1 C and a high rate capability.Moreover,capacity retention as high as 92%is observed after cycling at 4 C for 1000 times,far superior to many of the previously reported results.This facile strategy demonstrated here may shed new insight into the rational design of electrodes based on high-performance Zn//MnO_(2)batteries.
基金Projects(51774330, 52072411) supported by the National Natural Science Foundation of ChinaProject(2015) supported by the Teacher Research Foundation of Central South University,China+2 种基金Project(2022ZZTS0422) supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2021JJ20060) supported by the Natural Science Foundation of Hunan Province,ChinaProject(2021RC3001) supported by the Science and Technology Innovation Program of Hunan Province,China。
基金the NSFC(51702123)Shandong Province Higher Educational Youths Innovation Science and Technol-ogy Program(2019KJA018)+1 种基金the University of Jinan Science and Technology Planning Project(XKY2034)S.H.Yang thanks the start-up research funding from the University of Jinan.
文摘The key challenges in aqueous zinc-manganese dioxide batteries(MnO_(2)//Zn)are their poor electrochemical kinetics and stability,which are mainly due to low conductivity and the inevitable dissolution of MnO_(2).A syn-ergistic combination of a Co-doped𝜎σ-MnO_(2)electrode(Co-MnO_(2))and a Co(CH_(3)COO)_(2)•4H_(2)O(CoAc)electrolyte additive is here developed to design a high-performance aqueous MnO_(2)//Zn battery(denoted as a Co-MnO_(2)//Zn battery with CoAc).The introduction of Co ions(Co^(3+)/Co^(2+))into the𝜎σ-MnO_(2)electrode is achieved via a facile one-step electrodeposition method.Benefitting from the synergistic coupling effect of the Co-MnO_(2)electrode and the CoAc electrolyte additive,the fabricated Co-MnO_(2)//Zn battery with CoAc shows a commendable dis-charge capacity of 313.8 mAh g^(−1)at 0.5 A g^(−1),excellent rate performance,excellent durability over 1000 cycles(∼92%capacity retention at 1.0 A g^(−1))and admirable energy density(439.3 Wh kg^(−1)),which is a significant improvement compared with an un-doped𝜎σ-MnO_(2)//Zn battery.