The Mn Fe P0.56Si0.44 compound is investigated by x-ray diffraction, magnetic measurements, and x-ray absorption fine structure spectroscopy. It crystallizes in Fe2P-type structure with the lattice parameters a = b = ...The Mn Fe P0.56Si0.44 compound is investigated by x-ray diffraction, magnetic measurements, and x-ray absorption fine structure spectroscopy. It crystallizes in Fe2P-type structure with the lattice parameters a = b = 5.9823(0) and c = 3.4551(1) and undergoes a first-order phase transition at the Curie temperature of 255 K. The Fe K edge and Mn K edge x-ray absorption fine structure spectra show that Mn atoms mainly reside at 3g sites, while 3f sites are occupied by Fe atoms. The distances between the absorbing Fe atom and the first and second nearest neighbor Fe atoms in a 3f-layer shift from 2.65 and 4.01 in the ferromagnetic state to 2.61 and 3.96 in the paramagnetic phase. On the other hand, the distance between the 3g-layer and 3f-layer changes a little as 2.66 –2.73 below the Curie temperature and2.68 –2.75 above it.展开更多
钠离子电池因其成本低、资源丰富等优点而成为新一代储能设备.在各种正极中,隧道型Na_(0.44)MnO_(2)因其较大的Na^(+)通道,被认为是快速充电电池的合适正极材料,但仍然存在Na^(+)动力学缓慢等问题.本文首次提出了一种Na_(0.44)MnO_(2)...钠离子电池因其成本低、资源丰富等优点而成为新一代储能设备.在各种正极中,隧道型Na_(0.44)MnO_(2)因其较大的Na^(+)通道,被认为是快速充电电池的合适正极材料,但仍然存在Na^(+)动力学缓慢等问题.本文首次提出了一种Na_(0.44)MnO_(2)的新型离子交换方法,通过调节合成条件,可以很好地控制K^(+)残余量和Na_(0.44)MnO_(2)的尺寸.结果表明,Na_(0.44)MnO_(2)结构中的残留K^(+)扩大了Na^(+)的输运通道,小颗粒形貌缩短了Na^(+)的迁移距离,且晶体中的带状缺陷界面进一步加速了Na^(+)的输运.获得的Na_(0.44)MnO_(2)具有本征赝电容特性,在2-4 V和20 C电流下有79.0 mA h g^(-1)的优异倍率性能.长期循环测试表明,20 C下1000次循环的保持率为98.1%,0.5 C下200次循环的保持率为96.3%.本工作为用于快速充电储能装置的高倍率、高稳定性Na_(0.44)MnO_(2)正极的大规模生产提供了一条新途径.展开更多
Among the large energy storage batteries,the sodium ion batteries(SIBs)are attracted huge interest due to the fact of its abundant raw materials and low cost,and has become the most promising secondary battery.Tunnel-...Among the large energy storage batteries,the sodium ion batteries(SIBs)are attracted huge interest due to the fact of its abundant raw materials and low cost,and has become the most promising secondary battery.Tunnel-type sodium manganese oxides(TMOs)are industrialized cathode materials because of their simple synthesis method and proficient electrochemical performance.Na_(0.44)MnO_(2)(NMO)is considered the best candidate material for all tunnel-type structural materials.In this paper,the research progress in charge and discharge of cathode materials for tunnel-type structural SIBs is reviewed,the redox mechanism and all sorts of synthesis methods and different coating methods lead to different morphology and electrochemical properties of materials and the classification of electrolytes and nonaqueous electrolytes.The development and utility of aqueous solutions are discussed,and the mechanism is analyzed.Summarized the cationic potential of the transition metal oxide for tunnel structure,plays a vital role in predicting and designing the cathode material of this structure.In addition,the future opportunities and challenges for such tunnel-type SIBs in this field are described in detail.展开更多
Aqueous rechargeable batteries are a possible strategy for large-scale energy storage systems.However,limited choices of anode materials restrict their further application.Here we report phenazine(PNZ)as stable anode ...Aqueous rechargeable batteries are a possible strategy for large-scale energy storage systems.However,limited choices of anode materials restrict their further application.Here we report phenazine(PNZ)as stable anode materials in different alkali-ion(Li+,Na+,K+)electrolyte.A novel full cell is assembled by phenazine anode,Na0.44MnO2 cathode and 10 M NaOH electrolyte to further explore the electrochemical performance of phenazine anode.This battery is able to achieve high capacity(176.7 mAh·g^−1 at 4 C(1.2·Ag^−1)),ultralong cycling life(capacity retention of 80%after 13,000 cycles at 4 C),and excellent rate capacity(92 mAh·g^−1 at 100 C(30 A·g^−1)).The reaction mechanism of PNZ during charge—discharge process is demonstrated by in situ Raman spectroscopy,in situ Fourier transform infrared(FTIR)spectroscopy,X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations.Furthermore,the system is able to successfully operate at wide temperature range from−20 to 70°C and achieves remarkable electrochemical performance.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51461035,51161017,and 11404176)the Scientific Research Projects of the Higher Educational Department of Inner Mongolian Autonomous Region,China(Grant No.NJZZ14033)The XAFS measurement was performed under the approval of Photon Factory Program Advisory Committee(Proposal Nos.2012G095 and 2014G047)
文摘The Mn Fe P0.56Si0.44 compound is investigated by x-ray diffraction, magnetic measurements, and x-ray absorption fine structure spectroscopy. It crystallizes in Fe2P-type structure with the lattice parameters a = b = 5.9823(0) and c = 3.4551(1) and undergoes a first-order phase transition at the Curie temperature of 255 K. The Fe K edge and Mn K edge x-ray absorption fine structure spectra show that Mn atoms mainly reside at 3g sites, while 3f sites are occupied by Fe atoms. The distances between the absorbing Fe atom and the first and second nearest neighbor Fe atoms in a 3f-layer shift from 2.65 and 4.01 in the ferromagnetic state to 2.61 and 3.96 in the paramagnetic phase. On the other hand, the distance between the 3g-layer and 3f-layer changes a little as 2.66 –2.73 below the Curie temperature and2.68 –2.75 above it.
基金supported by the National Natural Science Foundation of China(52202327 and 51972326)the Science and Technology Commission of Shanghai Municipality(22ZR1471300)the Program of Shanghai Academic Research Leader(22XD1424300)。
文摘钠离子电池因其成本低、资源丰富等优点而成为新一代储能设备.在各种正极中,隧道型Na_(0.44)MnO_(2)因其较大的Na^(+)通道,被认为是快速充电电池的合适正极材料,但仍然存在Na^(+)动力学缓慢等问题.本文首次提出了一种Na_(0.44)MnO_(2)的新型离子交换方法,通过调节合成条件,可以很好地控制K^(+)残余量和Na_(0.44)MnO_(2)的尺寸.结果表明,Na_(0.44)MnO_(2)结构中的残留K^(+)扩大了Na^(+)的输运通道,小颗粒形貌缩短了Na^(+)的迁移距离,且晶体中的带状缺陷界面进一步加速了Na^(+)的输运.获得的Na_(0.44)MnO_(2)具有本征赝电容特性,在2-4 V和20 C电流下有79.0 mA h g^(-1)的优异倍率性能.长期循环测试表明,20 C下1000次循环的保持率为98.1%,0.5 C下200次循环的保持率为96.3%.本工作为用于快速充电储能装置的高倍率、高稳定性Na_(0.44)MnO_(2)正极的大规模生产提供了一条新途径.
基金supported by the National Natural Science Foundation of China (NSFC, Nos. 51804035, 51874079 and 51674068the Hebei Province Key Research and Development Plan Project (No.19211302D)+2 种基金the support from Natural Science Foundation of Hebei Province (No. E2018501091)The Fundamental Research Funds for the Central Universities (Nos. N172302001, N182306001, N182312007, N2023040)the support from Research Project on the Distribution of Heavy Metals in Soil and Comprehensive Utilization Technology of Tailings in Typical Iron Tailing Reservoir Areas of Hebei Province (No. 802060671901)
文摘Among the large energy storage batteries,the sodium ion batteries(SIBs)are attracted huge interest due to the fact of its abundant raw materials and low cost,and has become the most promising secondary battery.Tunnel-type sodium manganese oxides(TMOs)are industrialized cathode materials because of their simple synthesis method and proficient electrochemical performance.Na_(0.44)MnO_(2)(NMO)is considered the best candidate material for all tunnel-type structural materials.In this paper,the research progress in charge and discharge of cathode materials for tunnel-type structural SIBs is reviewed,the redox mechanism and all sorts of synthesis methods and different coating methods lead to different morphology and electrochemical properties of materials and the classification of electrolytes and nonaqueous electrolytes.The development and utility of aqueous solutions are discussed,and the mechanism is analyzed.Summarized the cationic potential of the transition metal oxide for tunnel structure,plays a vital role in predicting and designing the cathode material of this structure.In addition,the future opportunities and challenges for such tunnel-type SIBs in this field are described in detail.
基金This study was supported by the National Key R&D Program of China(Nos.2016YFB0901500 and 2016YFB0101201)the National Natural Science Foundation of China(No.51771094)+1 种基金Ministry of Education of China(Nos.B12015 and IRT13R30)Tianjin High-Tech(No.18JCZDJC31500).
文摘Aqueous rechargeable batteries are a possible strategy for large-scale energy storage systems.However,limited choices of anode materials restrict their further application.Here we report phenazine(PNZ)as stable anode materials in different alkali-ion(Li+,Na+,K+)electrolyte.A novel full cell is assembled by phenazine anode,Na0.44MnO2 cathode and 10 M NaOH electrolyte to further explore the electrochemical performance of phenazine anode.This battery is able to achieve high capacity(176.7 mAh·g^−1 at 4 C(1.2·Ag^−1)),ultralong cycling life(capacity retention of 80%after 13,000 cycles at 4 C),and excellent rate capacity(92 mAh·g^−1 at 100 C(30 A·g^−1)).The reaction mechanism of PNZ during charge—discharge process is demonstrated by in situ Raman spectroscopy,in situ Fourier transform infrared(FTIR)spectroscopy,X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations.Furthermore,the system is able to successfully operate at wide temperature range from−20 to 70°C and achieves remarkable electrochemical performance.
