Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this ...Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials.展开更多
The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) ...The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) and rare earth(RE) resources.In this work,the phase equilibria in low basicity region(w(CaO)/w(SiO2)<1) of CaO-SiO2-Nb2O5-(0-15 wt%)La2O3 system at 1373-1873 K were experimentally studied by thermodynamic equilibrium experiment,and then,the results were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).Additionally,an optimized method was proposed to process the compositions of equilibrium liquid phases at different temperatures.According to the experimental results,the univariate line between CaNb2O6,SiO2 and LaNbO4 primary phase fields,interface between CaNb2O6 and SiO2 primary phase fields and isothermal liquidus surfaces in SiO2 primary phase field were determined.Finally,the spatial phase diagram of CaO-SiO2-Nb2O5-La2O3 within specific region was constructed,and furthermore,the phase diagram was also presented in CaO-SiO2-Nb2O5 pseudo-ternary system with w(La2O3)=5 wt%,10 wt% and 15 wt%.The research results have guiding significance for the improvement of related phase diagram and the comprehensive utilization of Nb and RE resources.展开更多
A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce...A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:52372188,51902090,51922008,520721142023 Introduction of studying abroad talent program,the China Postdoctoral Science Foundation,Grant/Award Number:2019 M652546+3 种基金Xinxiang Major Science and Technology Projects,Grant/Award Number:21ZD001Henan Province Postdoctoral Start‐Up Foundation,Grant/Award Number:1901017Henan Center for Outstanding Overseas Scientists,Grant/Award Number:GZS2018003Overseas Expertise Introduction Project for Discipline Innovation,Grant/Award Number:D17007。
文摘Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials.
基金Project supported by the National Key R&D Program of China(2017YFC0805100)the National Natural Science Foundation of China(51774087)the Fundamental Research Funds for the Central Universities China(N162506002)
文摘The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) and rare earth(RE) resources.In this work,the phase equilibria in low basicity region(w(CaO)/w(SiO2)<1) of CaO-SiO2-Nb2O5-(0-15 wt%)La2O3 system at 1373-1873 K were experimentally studied by thermodynamic equilibrium experiment,and then,the results were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).Additionally,an optimized method was proposed to process the compositions of equilibrium liquid phases at different temperatures.According to the experimental results,the univariate line between CaNb2O6,SiO2 and LaNbO4 primary phase fields,interface between CaNb2O6 and SiO2 primary phase fields and isothermal liquidus surfaces in SiO2 primary phase field were determined.Finally,the spatial phase diagram of CaO-SiO2-Nb2O5-La2O3 within specific region was constructed,and furthermore,the phase diagram was also presented in CaO-SiO2-Nb2O5 pseudo-ternary system with w(La2O3)=5 wt%,10 wt% and 15 wt%.The research results have guiding significance for the improvement of related phase diagram and the comprehensive utilization of Nb and RE resources.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704010,51604003,U1760117)Key Laboratory Open Project Fund of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology)Ministry of Education(JKF18-02).
文摘A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.
