A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-ge...A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-gel method, acid base neutralization sedimentation method, hydrothermal method, and gas phase deposition method, the technology was relatively simplified and the elemental composition was controllable, without the use of openings and additives. A kind of multi-element composite porous metal oxide was obtained by pre-intercalation and decarburization. In order to increase the porosity of MoO3 material and promote the adsorption and diffusion of reactant molecules, the microstructure of MoO3 was studied. The preparation process of porous molybdenum trioxide by solid gas combination process was discussed, which provides an innovative idea for the design and preparation of new materials with a large specific surface area and other desirable properties.展开更多
Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1)...Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1),and rapid reaction kinetics in the electrolyte.However,searching for compatible anode materials to match with bromine has posed a challenge due to its highly corrosive nature.In this study,we developed oxygen-deficient MoO_(3) with TiO_(2) coating(referred to as MoO_(3-x)@TiO_(2))as an anode material to pair with a bromine cathode in static full batteries.The oxygen deficiency contributes to enhanced electronic and protonic diffusion within the MoO_(3-x)lattice,while the TiO_(2) coating mitigates structural dissolution and proton trapping during cycling.The MoO_(3-x)@TiO_(2) demonstrates fast charge storage kinetics and excellent resistance to bromine corrosion.The impressive compatibility between MoO_(3-x)@TiO_(2) and bromine enables the construction of membrane-less full batteries with exceptional rate capability and cyclic stability.The MoO_(3-x)@TiO_(2)-bromine battery achieves an energy density of70.8 W h kg^(-1)at a power density of 328.1 W kg^(-1),showcasing an impressive long-term cyclic life of 20,000 cycles.Our study provides valuable insights for the development of high-performance aqueous secondary batteries.展开更多
Aqueous zinc-ion batteries(ZIBs) have attracted significant attentions because of low cost and high reliability. However, conventional ZIBs are severely limited by the development of high energy density cathode materi...Aqueous zinc-ion batteries(ZIBs) have attracted significant attentions because of low cost and high reliability. However, conventional ZIBs are severely limited by the development of high energy density cathode materials with reversible Zn^(2+)insertion/extraction. Herein, a conducting polymer intercalated MoO_(3)(PMO) with extensively extended interlayer spacing is developed as a high-performance ZIBs cathode material. The interlayer spacing of PMO is prominently increased which results in an improved Zn^(2+)mobility during charge and discharge process. More significantly, the electrochemical results reveals that the intercalation of PANI facilitates the charge storage and reinforces the layered structure of MoO_(3), leading to a high capacity and good cycling stability. DFT calculation further reveals the intercalation of PANI into MoO_(3)significantly lower Zn^(2+)diffusion barrier. Benefit from these advantages, the ZIBs based on PMO electrode delivers a considerable capacity of 157 m Ah/g at 0.5 A/g and ameliorative stability with 63.4%capacity retention after 1000 cycles.展开更多
MoO_(3) is one of the most promising anode materials for aqueous aluminum batteries due to its high theoretical capacity and suitable aluminum insertion/de-insertion potential.However,the inferior cycling stability li...MoO_(3) is one of the most promising anode materials for aqueous aluminum batteries due to its high theoretical capacity and suitable aluminum insertion/de-insertion potential.However,the inferior cycling stability limits its further application,and the failure mechanism is still unclear.In this article,we provide a straightforward potential regulation technique to manage phase evolution during the charge/discharge process,which ultimately results in a markedly enhanced MoO_(3) electrode cycling stability.The failure mechanism study reveals that the excessive oxidation of the electrode during charge/discharge generates the H_(0.34)MoO_(3) phase,which has high solubility and is the primary cause of MoO_(3) deactivation.Although the dissolved Mo species will be deposited onto the electrode sheet again,the deposition is not electrochemically active and cannot contribute to the capacitance.Controlling the cutoff potential prevented the production of H_(0.34)MoO_(3),resulting in excellent cycling performance(80.1% capacity retention after 4000 cycles).The as-assembled α-MoO_(3)//MnO_(2) full battery exhibits high discharge plateaus(1.4 and 0.9 V),large specific capacity(200 mAhg^(-1) at 2 Ag^(-1)),and ultra-high coulombic efficiency(99%).The research presented here may contribute to the development of highly stable electrode materials for aqueous batteries.展开更多
X-ray photoelectron spectroscopy(XPS) and extended X-ray absorption fine structure(EXAFS) were used to characterize the structure of the mixture of molybdenum oxide and anatase calcined at 723 K. The results indicate ...X-ray photoelectron spectroscopy(XPS) and extended X-ray absorption fine structure(EXAFS) were used to characterize the structure of the mixture of molybdenum oxide and anatase calcined at 723 K. The results indicate that molybdenum oxide can disperse onto the surface of anatase(TiO 2) and the dispersion threshold is 11.2 mg in per gram of MoO 3 or 4.8 Mo atoms/nm 2 TiO 2. When the content of MoO 3 is below the dispersion threshold, MoO 3 species is in highly dispersed state interacting strongly with TiO 2 support and in discrete tetrahedral coordination, [MoO 4], on the surface of TiO 2. When the MoO 3 loading is above this value, MoO 3 exists in both dispersed phase and crystalline phase. MoO 3 in dispersed phase is still a discrete [MoO 4] tetrahedron; MoO 3 in crystal phase is in octahedral coordination.展开更多
In modern metallurgical industry,microwave thermal technique has many advantages as one efficient energy treatment in an electromagnetic form,such as internal self-generated heat,easy access to control a volumetric he...In modern metallurgical industry,microwave thermal technique has many advantages as one efficient energy treatment in an electromagnetic form,such as internal self-generated heat,easy access to control a volumetric heating process,and consensus on cleanliness,convenience and high efficiency of energy use.Both permittivity and permeability of molybdenite concentrate were measured for a further discussion about its electromagnetic heating coupling.A bidirectional coupling physics field in numerical modeling was undertaken to evaluate the microwave absorption potential and dielectric heating performance of molybdenite concentrate by the multi-physics finite element method.The electromagnetic morphology and the field distribution strength were described in the microwave reaction cavity.The electromagnetic field strength and the dissipation coefficient induced by temperature variation were represented throughout the whole heat chamber and at key parts of interest.Dependent temperature distribution was compared with that being obtained from a scenario by thermal conduction with a stable heat source.The molybdenite concentrate would be heated at surrounding temperature up to 593℃for 10 min by microwave energy that was transmitted by a rectangular waveguide.Scanning electron microscopy(SEM)patterns suggested that the polished and neat crystalline molybdenum trioxide(MoO_(3))products were achieved by the microwave heating process.The superiority via utilizing microwave thermal technique is expounded in the preparation strategy for molybdenum oxide or molybdenum metal.展开更多
基金Funded by National Natural Science Foundation of China(No.516722040)。
文摘A novel solid-gas reaction preparation technology was used to adjust the composition and microstructure of the composite crystal materials by changing the preparation parameters. Compared with the commonly used sol-gel method, acid base neutralization sedimentation method, hydrothermal method, and gas phase deposition method, the technology was relatively simplified and the elemental composition was controllable, without the use of openings and additives. A kind of multi-element composite porous metal oxide was obtained by pre-intercalation and decarburization. In order to increase the porosity of MoO3 material and promote the adsorption and diffusion of reactant molecules, the microstructure of MoO3 was studied. The preparation process of porous molybdenum trioxide by solid gas combination process was discussed, which provides an innovative idea for the design and preparation of new materials with a large specific surface area and other desirable properties.
基金the financial support from the National Key Research and Development Program of China(2022YFB2502003)the Guangdong Basic and Applied Basic Research Foundation(2023B1515040011)。
文摘Bromine has attracted significant attention as a cathode material for aqueous batteries due to its high reduction potential of 1.05 V(Br_(3)^(-)+2e~-■3Br~-),impressive theoretical specific capacity of 223 mA h g^(-1),and rapid reaction kinetics in the electrolyte.However,searching for compatible anode materials to match with bromine has posed a challenge due to its highly corrosive nature.In this study,we developed oxygen-deficient MoO_(3) with TiO_(2) coating(referred to as MoO_(3-x)@TiO_(2))as an anode material to pair with a bromine cathode in static full batteries.The oxygen deficiency contributes to enhanced electronic and protonic diffusion within the MoO_(3-x)lattice,while the TiO_(2) coating mitigates structural dissolution and proton trapping during cycling.The MoO_(3-x)@TiO_(2) demonstrates fast charge storage kinetics and excellent resistance to bromine corrosion.The impressive compatibility between MoO_(3-x)@TiO_(2) and bromine enables the construction of membrane-less full batteries with exceptional rate capability and cyclic stability.The MoO_(3-x)@TiO_(2)-bromine battery achieves an energy density of70.8 W h kg^(-1)at a power density of 328.1 W kg^(-1),showcasing an impressive long-term cyclic life of 20,000 cycles.Our study provides valuable insights for the development of high-performance aqueous secondary batteries.
基金financially supported by the National Natural Science Foundation of China (Nos. 51771058, 51801030)Natural Science Foundation of Guangdong Province (No. 2018A030310571)。
文摘Aqueous zinc-ion batteries(ZIBs) have attracted significant attentions because of low cost and high reliability. However, conventional ZIBs are severely limited by the development of high energy density cathode materials with reversible Zn^(2+)insertion/extraction. Herein, a conducting polymer intercalated MoO_(3)(PMO) with extensively extended interlayer spacing is developed as a high-performance ZIBs cathode material. The interlayer spacing of PMO is prominently increased which results in an improved Zn^(2+)mobility during charge and discharge process. More significantly, the electrochemical results reveals that the intercalation of PANI facilitates the charge storage and reinforces the layered structure of MoO_(3), leading to a high capacity and good cycling stability. DFT calculation further reveals the intercalation of PANI into MoO_(3)significantly lower Zn^(2+)diffusion barrier. Benefit from these advantages, the ZIBs based on PMO electrode delivers a considerable capacity of 157 m Ah/g at 0.5 A/g and ameliorative stability with 63.4%capacity retention after 1000 cycles.
基金the Youth Program of National Natural Science Foundation of China(grant nos.21905300,52277229,22109180,and 51877216)Taishan Scholar Foundation(grant no.tspd20210308)+5 种基金National Key Research and Development of China(grant no.2022YFA1503400)Key Projects of Shandong Key R&D plan(grant no.2019JZZY010506)Fundamental Research Funds for the Central Universities(grant no.21CX06011A)111 Program of National College Disciplinary Innovation(grant no.B03031)Natural Science Foundation of Shandong Province(grant nos.ZR202103040491 and ZR2020MB078)Research Project of State Key Laboratory for Heavy Oil Processing(grant no.SLKZZKT-2021).
文摘MoO_(3) is one of the most promising anode materials for aqueous aluminum batteries due to its high theoretical capacity and suitable aluminum insertion/de-insertion potential.However,the inferior cycling stability limits its further application,and the failure mechanism is still unclear.In this article,we provide a straightforward potential regulation technique to manage phase evolution during the charge/discharge process,which ultimately results in a markedly enhanced MoO_(3) electrode cycling stability.The failure mechanism study reveals that the excessive oxidation of the electrode during charge/discharge generates the H_(0.34)MoO_(3) phase,which has high solubility and is the primary cause of MoO_(3) deactivation.Although the dissolved Mo species will be deposited onto the electrode sheet again,the deposition is not electrochemically active and cannot contribute to the capacitance.Controlling the cutoff potential prevented the production of H_(0.34)MoO_(3),resulting in excellent cycling performance(80.1% capacity retention after 4000 cycles).The as-assembled α-MoO_(3)//MnO_(2) full battery exhibits high discharge plateaus(1.4 and 0.9 V),large specific capacity(200 mAhg^(-1) at 2 Ag^(-1)),and ultra-high coulombic efficiency(99%).The research presented here may contribute to the development of highly stable electrode materials for aqueous batteries.
基金the National Natural Science Foundation of China(No.2 97330 80 ) and the Major State Basic ResearchDevelopment Program(No.G2 0 0 0 0 775 0 3)
文摘X-ray photoelectron spectroscopy(XPS) and extended X-ray absorption fine structure(EXAFS) were used to characterize the structure of the mixture of molybdenum oxide and anatase calcined at 723 K. The results indicate that molybdenum oxide can disperse onto the surface of anatase(TiO 2) and the dispersion threshold is 11.2 mg in per gram of MoO 3 or 4.8 Mo atoms/nm 2 TiO 2. When the content of MoO 3 is below the dispersion threshold, MoO 3 species is in highly dispersed state interacting strongly with TiO 2 support and in discrete tetrahedral coordination, [MoO 4], on the surface of TiO 2. When the MoO 3 loading is above this value, MoO 3 exists in both dispersed phase and crystalline phase. MoO 3 in dispersed phase is still a discrete [MoO 4] tetrahedron; MoO 3 in crystal phase is in octahedral coordination.
基金Educational Science and Technology Project,Educational Department of Guizhou Province,China(No.2022005)。
文摘In modern metallurgical industry,microwave thermal technique has many advantages as one efficient energy treatment in an electromagnetic form,such as internal self-generated heat,easy access to control a volumetric heating process,and consensus on cleanliness,convenience and high efficiency of energy use.Both permittivity and permeability of molybdenite concentrate were measured for a further discussion about its electromagnetic heating coupling.A bidirectional coupling physics field in numerical modeling was undertaken to evaluate the microwave absorption potential and dielectric heating performance of molybdenite concentrate by the multi-physics finite element method.The electromagnetic morphology and the field distribution strength were described in the microwave reaction cavity.The electromagnetic field strength and the dissipation coefficient induced by temperature variation were represented throughout the whole heat chamber and at key parts of interest.Dependent temperature distribution was compared with that being obtained from a scenario by thermal conduction with a stable heat source.The molybdenite concentrate would be heated at surrounding temperature up to 593℃for 10 min by microwave energy that was transmitted by a rectangular waveguide.Scanning electron microscopy(SEM)patterns suggested that the polished and neat crystalline molybdenum trioxide(MoO_(3))products were achieved by the microwave heating process.The superiority via utilizing microwave thermal technique is expounded in the preparation strategy for molybdenum oxide or molybdenum metal.
