In light of the burgeoning energy technology sector and the ever-growing demand for lithium across diverse industrial domains,conventional lithium extraction methods have been proven inadequate due to their limited pr...In light of the burgeoning energy technology sector and the ever-growing demand for lithium across diverse industrial domains,conventional lithium extraction methods have been proven inadequate due to their limited production capacity and high operational costs.This work introduces a novel approach to the manganese-titanium based composite HMTO(Mn:Ti=1:4)lithium ion-sieve(LIS)nanospheres,employing lithium acetate dihydrate,manganese carbonate and titanium dioxide P25 as the primary materials.These nanospheres exhibit relatively uniform spherical morphology,narrow size distribution,small average particle size(ca.55 nm),large specific surface area(43.58 m^(2)g^(-1))and high surface O_(2)-content(59.01%).When utilized as the adsorbents for Li^(+)ions,the HMTO(Mn:Ti=1:4)LIS demonstrates a fast adsorption rate,approaching equilibrium within 6.0 h with an equilibrium adsorption capacity(qe)of 79.5 mg g^(-1)and a maximum adsorption capacity(qm)of 87.26 mg g^(-1)(initial concentration CO:1.8 g L^(-1)).In addition,the HMTO(Mn:Ti=1:4)also delivers a high lithium extraction from the simulated high magnesium-lithium molar ratio salt lake brine(Mg:Li=103),achieving a qeof 33.85 mg g^(-1)along with a remarkable selectivity(α_(Mg)^(Li)=2192.76).Particularly,the HMTO(Mn:Ti=1:4)LIS showcases a satisfactory recycling adsorption performance.The adsorption capacity remains at a high level,even that determined after the 5th cycle(55.45 mg g^(-1))surpasses that of the most recently reported adsorbents.Ultimately,the fantastic synergistic lithium adsorption mechanism is deliberately uncovered by leveraging the ion exchange principles and molecular dynamics(MD)simulations.展开更多
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ...Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties.展开更多
The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permangan...The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permanganate as a surface treatment. The surface-modified manganese sand was found to be most efficient at removing iron and manganese from water. The metal concentrations in filtered effluent were between 0.01 and 0.04 mg/L, which is far lower than the standard for recycle water. A concen-tration of 5% KMnO4 was found to be most effective as surface modifier. The surface of the manganese sand modified by 5% KMnO4 was examined and found to be covered with a dense membrane of some compound. The membrane had the advantages of uniform texture, large surface area and physical and chemical stability. It was effective at removing iron and manganese from mine water.展开更多
The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the ba...The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the basis of the present X-ray diffraction results and the literature is likely to be a solid solution Na(Cl)x(BH4)(1-x), possessing a cubic Na Cl-type crystalline structure. No presence of any crystalline hydride was detected by powder X-ray diffraction which clearly shows that NaBH4in the initial mixture must have reacted with MnCl2forming a Na Cl-type by-product and another hydride that does not exhibit X-ray Bragg diffraction peaks. Mass spectrometry(MS) of gas released from the ball milled mixture during combined MS/thermogravimetric analysis(TGA)/differential scanning calorimetry(DSC) experiments, confirms mainly hydrogen(H2) with a small quantity of diborane gas, B2H6. The Fourier transform infra-red(FT-IR) spectrum of the ball milled(2NaBH4+ MnCl2) is quite similar to the FT-IR spectrum of crystalline manganese borohydride, c-Mn(BH4)2, synthesized by ball milling, which strongly suggests that the amorphous hydride mechano-chemically synthesized during ball milling could be an amorphous manganese borohydride. Remarkably, the process of solvent filtration and extraction at 42 °C, resulted in the transformation of mechano-chemically synthesized amorphous manganese borohydride to a nanostructured,crystalline, c-Mn(BH4)2hydride.展开更多
Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support （Al2O3, SiO2 and TiO2） and Mn loading were investigated. These ...Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support （Al2O3, SiO2 and TiO2） and Mn loading were investigated. These catalysts were characterized with N2 adsorption, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction techniques. Methane conversion varied in a large range depending on supports or Mn loading. Al2O3 supported 15% Mn catalyst exhibited better activity toward methane catalytic oxidation. The manganese state and oxygen species played an important role in the catalytic performance,展开更多
There is an urgent need for low-cost,high-energy-density,environmentally friendly energy storage devices to fulfill the rapidly increasing need for electrical energy storage.Multi-electron redox is considerably crucia...There is an urgent need for low-cost,high-energy-density,environmentally friendly energy storage devices to fulfill the rapidly increasing need for electrical energy storage.Multi-electron redox is considerably crucial for the development of high-energy-density cathodes.Here we present highperformance aqueous zinc-manganese batteries with reversible Mn2+/Mn4+ double redox.The active Mn4+is generated in situ from the Mn2+-containing MnOx nanoparticles and electrolyte.Benefitting from the low crystallinity of the birnessite-type MnO2 as well as the electrolyte with Mn2+additive,the MnOX cathode achieves an ultrahigh energy density with a peak of845.1 Wh kg-1 and an ultralong lifespan of 1500 cycles.The combination of electrochemical measurements and material characterization reveals the reversible Mn2+/Mn4+double redox(birnessite-type MnO2? monoclinic MnOOH and spinel ZnMn2O4 H?Mn2+ions).The reversible Mn2+/Mn4+double redox electrode reaction mechanism offers new opportunities for the design of low-cost,high-energy-density cathodes for advanced rechargeable aqueous batteries.展开更多
Cation vacancies can bring numerous surprising characters due to its multifarious electron and orbit distribution.In this work,d-MnO_(2) with alkali-ion(K,Na,Li)associated manganese(Mn)vacancies is fabricated by a sim...Cation vacancies can bring numerous surprising characters due to its multifarious electron and orbit distribution.In this work,d-MnO_(2) with alkali-ion(K,Na,Li)associated manganese(Mn)vacancies is fabricated by a simple hydrothermal reaction,and the correlation between their electronic structure and pseudocapacitance are systematically investigated.FESEM/TEM images have shown that the morphology of MnO_(2) is obviously changed after the introducing of cation vacancies.The position of alkali-ion in MnO_(2) structure can be controlled by adjusting the ion concentration.XRD patterns and Raman spectra demonstrate that the alkali-ion is embedded in Mn vacancies at low concentration,while entered the interlayer of MnO_(2) at high concentration.The existence of Mn vacancies will resulting in the distortion of neighboring atoms,leading to the electronic delocalization,and thus enhancing the conductivity,pseudocapacitance and rate capability of MnO_(2).Accordingly,the specific capacitances of optimized 0.4 KMO,0.4 NaMO and 0.4 LiMO samples are enhanced about 1.9,1.6 and 1.6 times compared to pure MnO_(2).Meanwhile,the rate performance has also been improved about 76%,46%and 42%,respectively.Theoretical calculations further confirm that the Mn vacancies can generate additional occupancy states and cause an increase in carrier concentration,which will improve the conductivity and further boost the pseudocapacitance of MnO_(2).This result open up a promising approach to explore active and durable electrode materials.展开更多
Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials...Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials.In this work,we present an intercalation mechanism-based cathode materials for AZIB,i.e.the vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural stability.Systematic in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous electrolyte.The demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs.展开更多
Manganese(Mn)-based materials are considered as one of the most promising cathodes in zinc-ion batteries(ZIBs) for large-scale energy storage applications because of their multivalence, cost-effectiveness,natural avai...Manganese(Mn)-based materials are considered as one of the most promising cathodes in zinc-ion batteries(ZIBs) for large-scale energy storage applications because of their multivalence, cost-effectiveness,natural availability, low toxicity, satisfactory capacity, and high operating voltage. In this review, the research status and related interface engineering strategies of Mn-based oxide cathode electrode materials for ZIB in recent years are summarized. Specifically, the review will focus on three types of interface engineering strategies, including interface reconstruction via cathode, interface reconstruction electrolyte, and protection via artificial cathode-electrolyte interphase(CEI) layer, within the context of their evolution of interface layer and corresponding electrochemical performance. A series of experimental variables, such as crystal structure, electrochemical reaction mechanism, and the necessary connection for the formation and evolution of interface layer, will be carefully analyzed by combining various advanced characterization techniques and theoretical calculations. Finally, suggestions and strategies are provided for reasonably designing the cathode-electrolyte interface to realize the excellent performance of Mn-based oxide zinc-based batteries.展开更多
基金supported by the National Natural Science Foundation of China(22075304,22378390)Natural Science Foundation of Shandong Province,China(ZR2022MB075)+2 种基金State Key Laboratory of Organic-Inorganic Composites(oic-202401016)State Key Laboratory of Chemical Engineering(SKL-ChE-24A02)Beijing Natural Science Foundation,China(3222050).
文摘In light of the burgeoning energy technology sector and the ever-growing demand for lithium across diverse industrial domains,conventional lithium extraction methods have been proven inadequate due to their limited production capacity and high operational costs.This work introduces a novel approach to the manganese-titanium based composite HMTO(Mn:Ti=1:4)lithium ion-sieve(LIS)nanospheres,employing lithium acetate dihydrate,manganese carbonate and titanium dioxide P25 as the primary materials.These nanospheres exhibit relatively uniform spherical morphology,narrow size distribution,small average particle size(ca.55 nm),large specific surface area(43.58 m^(2)g^(-1))and high surface O_(2)-content(59.01%).When utilized as the adsorbents for Li^(+)ions,the HMTO(Mn:Ti=1:4)LIS demonstrates a fast adsorption rate,approaching equilibrium within 6.0 h with an equilibrium adsorption capacity(qe)of 79.5 mg g^(-1)and a maximum adsorption capacity(qm)of 87.26 mg g^(-1)(initial concentration CO:1.8 g L^(-1)).In addition,the HMTO(Mn:Ti=1:4)also delivers a high lithium extraction from the simulated high magnesium-lithium molar ratio salt lake brine(Mg:Li=103),achieving a qeof 33.85 mg g^(-1)along with a remarkable selectivity(α_(Mg)^(Li)=2192.76).Particularly,the HMTO(Mn:Ti=1:4)LIS showcases a satisfactory recycling adsorption performance.The adsorption capacity remains at a high level,even that determined after the 5th cycle(55.45 mg g^(-1))surpasses that of the most recently reported adsorbents.Ultimately,the fantastic synergistic lithium adsorption mechanism is deliberately uncovered by leveraging the ion exchange principles and molecular dynamics(MD)simulations.
基金supported by the National Key Research and Development Program of China(2022YFE0206300)the National Natural Science Foundation of China(22209047,U21A2081,22075074)+2 种基金Natural Science Foundation of Hunan Province(2020JJ5035)Hunan Provincial Department of Education Outstanding Youth Project(23B0037)Macao Science and Technology Development Fund(Macao SAR,FDCT-0096/2020/A2).
文摘Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties.
基金provided by the National Hi-tech Research and Development Program of China (No.2008AA06z305)the National Natural Science Foundation of China (No.50678172)the Science and Technology Research Program of the Ministry of Education of China (No.107022)
文摘The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permanganate as a surface treatment. The surface-modified manganese sand was found to be most efficient at removing iron and manganese from water. The metal concentrations in filtered effluent were between 0.01 and 0.04 mg/L, which is far lower than the standard for recycle water. A concen-tration of 5% KMnO4 was found to be most effective as surface modifier. The surface of the manganese sand modified by 5% KMnO4 was examined and found to be covered with a dense membrane of some compound. The membrane had the advantages of uniform texture, large surface area and physical and chemical stability. It was effective at removing iron and manganese from mine water.
基金supported by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery grant to Prof. R.A. Varin
文摘The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the basis of the present X-ray diffraction results and the literature is likely to be a solid solution Na(Cl)x(BH4)(1-x), possessing a cubic Na Cl-type crystalline structure. No presence of any crystalline hydride was detected by powder X-ray diffraction which clearly shows that NaBH4in the initial mixture must have reacted with MnCl2forming a Na Cl-type by-product and another hydride that does not exhibit X-ray Bragg diffraction peaks. Mass spectrometry(MS) of gas released from the ball milled mixture during combined MS/thermogravimetric analysis(TGA)/differential scanning calorimetry(DSC) experiments, confirms mainly hydrogen(H2) with a small quantity of diborane gas, B2H6. The Fourier transform infra-red(FT-IR) spectrum of the ball milled(2NaBH4+ MnCl2) is quite similar to the FT-IR spectrum of crystalline manganese borohydride, c-Mn(BH4)2, synthesized by ball milling, which strongly suggests that the amorphous hydride mechano-chemically synthesized during ball milling could be an amorphous manganese borohydride. Remarkably, the process of solvent filtration and extraction at 42 °C, resulted in the transformation of mechano-chemically synthesized amorphous manganese borohydride to a nanostructured,crystalline, c-Mn(BH4)2hydride.
基金supported by the New Century Excellent Talent Project of China (NCET-05-0783).
文摘Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support （Al2O3, SiO2 and TiO2） and Mn loading were investigated. These catalysts were characterized with N2 adsorption, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction techniques. Methane conversion varied in a large range depending on supports or Mn loading. Al2O3 supported 15% Mn catalyst exhibited better activity toward methane catalytic oxidation. The manganese state and oxygen species played an important role in the catalytic performance,
基金supported by the National Natural Science Foundation of China(Grant No.51772331)the National Key Technologies R&D Program(Grant No.2018YFB1106000).
文摘There is an urgent need for low-cost,high-energy-density,environmentally friendly energy storage devices to fulfill the rapidly increasing need for electrical energy storage.Multi-electron redox is considerably crucial for the development of high-energy-density cathodes.Here we present highperformance aqueous zinc-manganese batteries with reversible Mn2+/Mn4+ double redox.The active Mn4+is generated in situ from the Mn2+-containing MnOx nanoparticles and electrolyte.Benefitting from the low crystallinity of the birnessite-type MnO2 as well as the electrolyte with Mn2+additive,the MnOX cathode achieves an ultrahigh energy density with a peak of845.1 Wh kg-1 and an ultralong lifespan of 1500 cycles.The combination of electrochemical measurements and material characterization reveals the reversible Mn2+/Mn4+double redox(birnessite-type MnO2? monoclinic MnOOH and spinel ZnMn2O4 H?Mn2+ions).The reversible Mn2+/Mn4+double redox electrode reaction mechanism offers new opportunities for the design of low-cost,high-energy-density cathodes for advanced rechargeable aqueous batteries.
基金supported by Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ18E030005,LY18E060005,LY19E020006,LY18E020007National Natural Science Foundation of China(No.51902301)。
文摘Cation vacancies can bring numerous surprising characters due to its multifarious electron and orbit distribution.In this work,d-MnO_(2) with alkali-ion(K,Na,Li)associated manganese(Mn)vacancies is fabricated by a simple hydrothermal reaction,and the correlation between their electronic structure and pseudocapacitance are systematically investigated.FESEM/TEM images have shown that the morphology of MnO_(2) is obviously changed after the introducing of cation vacancies.The position of alkali-ion in MnO_(2) structure can be controlled by adjusting the ion concentration.XRD patterns and Raman spectra demonstrate that the alkali-ion is embedded in Mn vacancies at low concentration,while entered the interlayer of MnO_(2) at high concentration.The existence of Mn vacancies will resulting in the distortion of neighboring atoms,leading to the electronic delocalization,and thus enhancing the conductivity,pseudocapacitance and rate capability of MnO_(2).Accordingly,the specific capacitances of optimized 0.4 KMO,0.4 NaMO and 0.4 LiMO samples are enhanced about 1.9,1.6 and 1.6 times compared to pure MnO_(2).Meanwhile,the rate performance has also been improved about 76%,46%and 42%,respectively.Theoretical calculations further confirm that the Mn vacancies can generate additional occupancy states and cause an increase in carrier concentration,which will improve the conductivity and further boost the pseudocapacitance of MnO_(2).This result open up a promising approach to explore active and durable electrode materials.
基金supported by the grants from the Chinese Academy of Sciences(124GJHZ2023031MI)the National Natural Science Foundation of China(52173274)+1 种基金the National Key R&D Project from the Ministry of Science and Technology(2021YFA1201603)the Fundamental Research Funds for the Central Universities.
文摘Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials.In this work,we present an intercalation mechanism-based cathode materials for AZIB,i.e.the vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural stability.Systematic in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous electrolyte.The demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs.
基金financial support from the National Natural Science Foundation of China (No. 21676036)the Natural Science Foundation of Chongqing (No. CSTB2023NSCQMSX0580)。
文摘Manganese(Mn)-based materials are considered as one of the most promising cathodes in zinc-ion batteries(ZIBs) for large-scale energy storage applications because of their multivalence, cost-effectiveness,natural availability, low toxicity, satisfactory capacity, and high operating voltage. In this review, the research status and related interface engineering strategies of Mn-based oxide cathode electrode materials for ZIB in recent years are summarized. Specifically, the review will focus on three types of interface engineering strategies, including interface reconstruction via cathode, interface reconstruction electrolyte, and protection via artificial cathode-electrolyte interphase(CEI) layer, within the context of their evolution of interface layer and corresponding electrochemical performance. A series of experimental variables, such as crystal structure, electrochemical reaction mechanism, and the necessary connection for the formation and evolution of interface layer, will be carefully analyzed by combining various advanced characterization techniques and theoretical calculations. Finally, suggestions and strategies are provided for reasonably designing the cathode-electrolyte interface to realize the excellent performance of Mn-based oxide zinc-based batteries.
