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1.
Yan-Fang Zhu Dr. Yao Xiao Dr. Wei-Bo Hua Dr. Sylvio Indris Prof. Shi-Xue Dou Prof. Yu-Guo Guo Prof. Shu-Lei Chou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9385-9390
Structural evolution of the cathode during cycling plays a vital role in the electrochemical performance of sodium-ion batteries. A strategy based on engineering the crystal structure coupled with chemical substitution led to the design of the layered P2@P3 integrated spinel oxide cathode Na0.5Ni0.1Co0.15Mn0.65Mg0.1O2, which shows excellent sodium-ion half/full battery performance. Combined analyses involving scanning transmission electron microscopy with atomic resolution as well as in situ synchrotron-based X-ray absorption spectra and in situ synchrotron-based X-ray diffraction patterns led to visualization of the inherent layered P2@P3 integrated spinel structure, charge compensation mechanism, structural evolution, and phase transition. This study provides an in-depth understanding of the structure-performance relationship in this structure and opens up a novel field based on manipulating structural evolution for the design of high-performance battery cathodes. 相似文献
2.
Yao Xiao Yan‐Fang Zhu Wei Xiang Zhen‐Guo Wu Yong‐Chun Li Jing Lai Shi Li Enhui Wang Zu‐Guang Yang Chun‐Liu Xu Ben‐He Zhong Xiao‐Dong Guo 《Angewandte Chemie (International ed. in English)》2020,59(4):1491-1495
Demands for large‐scale energy storage systems have driven the development of layered transition‐metal oxide cathodes for room‐temperature rechargeable sodium ion batteries (SIBs). Now, an abnormal layered‐tunnel heterostructure Na0.44Co0.1Mn0.9O2 cathode material induced by chemical element substitution is reported. By virtue of beneficial synergistic effects, this layered‐tunnel electrode shows outstanding electrochemical performance in sodium half‐cell system and excellent compatibility with hard carbon anode in sodium full‐cell system. The underlying formation process, charge compensation mechanism, phase transition, and sodium‐ion storage electrochemistry are clearly articulated and confirmed through combined analyses of in situ high‐energy X‐ray diffraction and ex situ X‐ray absorption spectroscopy as well as operando X‐ray diffraction. This crystal structure engineering regulation strategy offers a future outlook into advanced cathode materials for SIBs. 相似文献
3.
Zichao Yan Liang Tang Yangyang Huang Weibo Hua Yong Wang Rong Liu Qinfen Gu Sylvio Indris Shu‐Lei Chou Yunhui Huang Minghong Wu Shi‐Xue Dou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(5):1426-1430
Low‐cost layered oxides free of Ni and Co are considered to be the most promising cathode materials for future sodium‐ion batteries. Biphasic Na0.78Cu0.27Zn0.06Mn0.67O2 obtained via superficial atomic‐scale P3 intergrowth with P2 phase induced by Zn doping, consisting of inexpensive transition metals, is a promising cathode for sodium‐ion batteries. The P3 phase as a covering layer in this composite shows not only in excellent electrochemical performance but also its tolerance to moisture. The results indicate that partial Zn substitutes can effectively control biphase formation for improving the structural/electrochemical stability as well as the ionic diffusion coefficient. Based on in situ synchrotron X‐ray diffraction coupled with electron‐energy‐loss spectroscopy, a possible Cu2+/3+ redox reaction mechanism has now been revealed. 相似文献
4.
Mingzhe Chen Weibo Hua Jin Xiao David Cortie Xiaodong Guo Enhui Wang Qinfen Gu Zhe Hu Sylvio Indris Xiao‐Lin Wang Shu‐Lei Chou Shi‐Xue Dou 《Angewandte Chemie (International ed. in English)》2020,59(6):2449-2456
Herein, we introduce a 4.0 V class high‐voltage cathode material with a newly recognized sodium superionic conductor (NASICON)‐type structure with cubic symmetry (space group P213), Na3V(PO3)3N. We synthesize an N‐doped graphene oxide‐wrapped Na3V(PO3)3N composite with a uniform carbon coating layer, which shows excellent rate performance and outstanding cycling stability. Its air/water stability and all‐climate performance were carefully investigated. A near‐zero volume change (ca. 0.40 %) was observed for the first time based on in situ synchrotron X‐ray diffraction, and the in situ X‐ray absorption spectra revealed the V3.2+/V4.2+ redox reaction with high reversibility. Its 3D sodium diffusion pathways were demonstrated with distinctive low energy barriers. Our results indicate that this high‐voltage NASICON‐type Na3V(PO3)3N composite is a competitive cathode material for sodium‐ion batteries and will receive more attention and studies in the future. 相似文献
5.
Lithium‐Rich Layered Oxide Li1.18Ni0.15Co0.15Mn0.52O2 as the Cathode Material for Hybrid Sodium‐Ion Batteries
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Zhixuan Wei Dr. Yu Gao Lei Wang Chaoyang Zhang Xiaofei Bian Qiang Fu Prof. Chunzhong Wang Prof. Yingjin Wei Dr. Fei Du Prof. Gang Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11610-11616
Li‐rich layered oxide Li1.18Ni0.15Co0.15Mn0.52O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium‐ion battery and its Na+ storage properties are comprehensively studied in terms of galvanostatic charge–discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium‐ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g?1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g?1 for 200 cycles at 5 C rate. Moreover, ex situ ICP‐OES suggests interesting mixed‐ions migration processes: In the initial two cycles, only Li+ can intercalate into the LNCM cathode, whereas both Li+ and Na+ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge–discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium‐ion batteries. 相似文献
6.
Electrochemical and Structural Study of Layered P2‐Type Na2/3Ni1/3Mn2/3O2 as Cathode Material for Sodium‐Ion Battery
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Yanfen Wen Dr. Bei Wang Guang Zeng Prof. Kazuhiro Nogita Delai Ye Prof. Lianzhou Wang 《化学:亚洲杂志》2015,10(3):661-666
P2‐type Na2/3Ni1/3Mn2/3O2 was synthesized by a controlled co‐precipitation method followed by a high‐temperature solid‐state reaction and was used as a cathode material for a sodium‐ion battery (SIB). The electrochemical behavior of this layered material was studied and an initial discharge capacity of 151.8 mA h g?1 was achieved in the voltage range of 1.5–3.75 V versus Na+/Na. The retained discharge capacity was found to be 123.5 mA h g?1 after charging/discharging 50 cycles, approximately 81.4 % of the initial discharge capacity. In situ X‐ray diffraction analysis was used to investigate the sodium insertion and extraction mechanism and clearly revealed the reversible structural changes of the P2‐Na2/3Ni1/3Mn2/3O2 and no emergence of the O2‐Ni1/3Mn2/3O2 phase during the cycling test, which is important for designing stable and high‐performance SIB cathode materials. 相似文献
7.
Sebastian Vogel Maxim Bykov Elena Bykova Sebastian Wendl Simon D. Kloß Anna Pakhomova Natalia Dubrovinskaia Leonid Dubrovinsky Wolfgang Schnick 《Angewandte Chemie (International ed. in English)》2020,59(7):2730-2734
Owing to its outstanding elastic properties, the nitride spinel γ‐Si3N4 is of considered interest for materials scientists and chemists. DFT calculations suggest that Si3N4‐analog beryllium phosphorus nitride BeP2N4 adopts the spinel structure at elevated pressures as well and shows outstanding elastic properties. Herein, we investigate phenakite‐type BeP2N4 by single‐crystal synchrotron X‐ray diffraction and report the phase transition into the spinel‐type phase at 47 GPa and 1800 K in a laser‐heated diamond anvil cell. The structure of spinel‐type BeP2N4 was refined from pressure‐dependent in situ synchrotron powder X‐ray diffraction measurements down to ambient pressure, which proves spinel‐type BeP2N4 a quenchable and metastable phase at ambient conditions. Its isothermal bulk modulus was determined to 325(8) GPa from equation of state, which indicates that spinel‐type BeP2N4 is an ultraincompressible material. 相似文献
8.
Biwei Xiao Hanshuo Liu Ning Chen Mohammad Norouzi Banis Haijun Yu Jianwen Liang Qian Sun Tsun‐Kong Sham Ruying Li Mei Cai Gianluigi A. Botton Xueliang Sun 《Angewandte Chemie (International ed. in English)》2020,59(34):14313-14320
Li‐ and Mn‐rich layered oxides are among the most promising cathode materials for Li‐ion batteries with high theoretical energy density. Its practical application is, however, hampered by the capacity and voltage fade after long cycling. Herein, a finite difference method for near‐edge structure (FDMNES) code was combined with in situ X‐ray absorption spectroscopy (XAS) and transmission electron microscopy/electron energy loss spectroscopy (TEM/EELS) to investigate the evolution of transition metals (TMs) in fresh and heavily cycled electrodes. Theoretical modeling reveals a recurring partially reversible LiMn2O4‐like sub‐nanodomain formation/dissolution process during each charge/discharge, which accumulates gradually and accounts for the Mn phase transition. From the modeling of spectra and maps of the valence state over large regions of the cathodes, it was found that the phase change is size‐dependent. After prolonged cycling, the TMs displayed different levels of inactivity. 相似文献
9.
Mingzhe Chen Jin Xiao Weibo Hua Zhe Hu Wanlin Wang Qinfen Gu Yuxin Tang Shu‐Lei Chou Hua‐Kun Liu Shi‐Xue Dou 《Angewandte Chemie (International ed. in English)》2020,59(29):12076-12083
Titanium‐based polyanions have been intensively investigated for sodium‐ion batteries owing to their superior structural stability and thermal safety. However, their low working potential hindered further applications. Now, a cation and anion dual doping strategy is used to boost the redox potential of Ti‐based cathodes of Na3Ti0.5V0.5(PO3)3N as a new cathode material for sodium ion batteries. Both the Ti3+/Ti4+ and V3+/V4+ redox couples are reversibly accessed, leading to two distinctive voltage platforms at ca. 3.3 V and ca. 3.8 V, respectively. The remarkably improved cycling stability (86.3 %, 3000 cycles) can be ascribed to the near‐zero volume strain in this unusual cubic symmetry, which has been demonstrated by in situ synchrotron‐based X‐ray diffraction. First‐principles calculations reveal its well‐interconnected 3D Na diffusion pathways with low energy barriers, and the two‐sodium‐extracted intermediate NaTi0.5V0.5(PO3)3N is also a stable phase according to formation energy calculations. 相似文献
10.
Hierarchical Surface Atomic Structure of a Manganese‐Based Spinel Cathode for Lithium‐Ion Batteries
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Dr. Sanghan Lee Gabin Yoon Minseul Jeong Min‐Joon Lee Prof. Kisuk Kang Prof. Jaephil Cho 《Angewandte Chemie (International ed. in English)》2015,54(4):1153-1158
The increasing use of lithium‐ion batteries (LIBs) in high‐power applications requires improvement of their high‐temperature electrochemical performance, including their cyclability and rate capability. Spinel lithium manganese oxide (LiMn2O4) is a promising cathode material because of its high stability and abundance. However, it exhibits poor cycling performance at high temperatures owing to Mn dissolution. Herein we show that when stoichiometric lithium manganese oxide is coated with highly doped spinels, the resulting epitaxial coating has a hierarchical atomic structure consisting of cubic‐spinel, tetragonal‐spinel, and layered structures, and no interfacial phase is formed. In a practical application of the coating to doped spinel, the material retained 90 % of its capacity after 800 cycles at 60 °C. Thus, the formation of an epitaxial coating with a hierarchical atomic structure could enhance the electrochemical performance of LIB cathode materials while preventing large losses in capacity. 相似文献
11.
In Situ Three‐Dimensional Synchrotron X‐Ray Nanotomography of the (De)lithiation Processes in Tin Anodes
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Dr. Jiajun Wang Dr. Yu‐chen Karen Chen‐Wiegart Dr. Jun Wang 《Angewandte Chemie (International ed. in English)》2014,53(17):4460-4464
The three‐dimensional quantitative analysis and nanometer‐scale visualization of the microstructural evolutions of a tin electrode in a lithium‐ion battery during cycling is described. Newly developed synchrotron X‐ray nanotomography provided an invaluable tool. Severe microstructural changes occur during the first delithiation and the subsequent second lithiation, after which the particles reach a structural equilibrium with no further significant morphological changes. This reveals that initial delithiation and subsequent lithiation play a dominant role in the structural instability that yields mechanical degradation. This in situ 3D quantitative analysis and visualization of the microstructural evolution on the nanometer scale by synchrotron X‐ray nanotomography should contribute to our understanding of energy materials and improve their synthetic processing. 相似文献
12.
Graphite‐Nanoplate‐Coated Bi2S3 Composite with High‐Volume Energy Density and Excellent Cycle Life for Room‐Temperature Sodium–Sulfide Batteries
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Wei‐Jie Li Chao Han Dr. Shu‐Lei Chou Prof. Jia‐Zhao Wang Prof. Zhen Li Yong‐Mook Kang Prof. Hua‐Kun Liu Prof. Shi‐Xue Dou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):590-597
Graphite‐nanoplate‐coated Bi2S3 composite (Bi2S3@C) has been prepared by a simple, scalable, and energy‐efficient precipitation method combined with ball milling. The Bi2S3@C composite was used as the cathode material for sodium–sulfide batteries. It delivered an initial capacity of 550 mAh g?1 and high stable specific energy in the range of 275–300 Wh kg?1 at 0.1 C, with an enhanced capacity retention of 69 % over 100 cycles. The unique structure demonstrates superior cycling stability, with a capacity drop of 0.3 % per cycle over 100 cycles, compared with that of bare Bi2S3. The sodium storage mechanism of Bi2S3 was investigated based on ex situ X‐ray diffraction and scanning transmission electron microscopy. 相似文献
13.
Dr. Hongcai Gao Prof. John B. Goodenough 《Angewandte Chemie (International ed. in English)》2016,55(41):12768-12772
A symmetric sodium‐ion battery with an aqueous electrolyte is demonstrated; it utilizes the NASICON‐structured Na3MnTi(PO4)3 as both the anode and the cathode. The NASICON‐structured Na3MnTi(PO4)3 possesses two electrochemically active transition metals with the redox couples of Ti4+/Ti3+ and Mn3+/Mn2+ working on the anode and cathode sides, respectively. The symmetric cell based on this bipolar electrode material exhibits a well‐defined voltage plateau centered at about 1.4 V in an aqueous electrolyte with a stable cycle performance and superior rate capability. The advent of aqueous symmetric sodium‐ion battery with high safety and low cost may provide a solution for large‐scale stationary energy storage. 相似文献
14.
A bifunctional oxygen electrocatalyst composed of iron carbide (Fe3C) nanoparticles encapsulated by nitrogen doped carbon sheets is reported. X‐ray photoelectron spectroscopy and X‐ray absorption near edge structure revealed the presence of several kinds of active sites (Fe?Nx sites, N doping sites) and the modulated electron structure of nitrogen doped carbon sheets. Fe3C@N‐CSs shows excellent oxygen evolution and oxygen reduction catalytic activity owing to the modulated electron structure by encapsulated Fe3C core via biphasic interfaces electron interaction, which can lower the free energy of intermediate, strengthen the bonding strength and enhance conductivity. Meanwhile, the contribution of the Fe?Nx sites, N doping sites and the effect of Fe3C core for the electrocatalytic oxygen reaction is originally revealed. The Fe3C@N‐CSs air electrode‐based zinc‐air battery demonstrates a high open circuit potential of 1.47 V, superior charge‐discharge performance and long lifetime, which outperforms the noble metal‐based zinc‐air battery. 相似文献
15.
Lin Li Luojia Liu Zhe Hu Yong Lu Qiannan Liu Song Jin Qiu Zhang Shuo Zhao Shu‐Lei Chou 《Angewandte Chemie (International ed. in English)》2020,59(31):12917-12924
Graphite shows great potential as an anode material for rechargeable metal‐ion batteries because of its high abundance and low cost. However, the electrochemical performance of graphite anode materials for rechargeable potassium‐ion batteries needs to be further improved. Reported herein is a natural graphite with superior rate performance and cycling stability obtained through a unique K+‐solvent co‐intercalation mechanism in a 1 m KCF3SO3 diethylene glycol dimethyl ether electrolyte. The co‐intercalation mechanism was demonstrated by ex situ Fourier transform infrared spectroscopy and in situ X‐ray diffraction. Moreover, the structure of the [K‐solvent]+ complexes intercalated with the graphite and the conditions for reversible K+‐solvent co‐intercalation into graphite are proposed based on the experimental results and first‐principles calculations. This work provides important insights into the design of natural graphite for high‐performance rechargeable potassium‐ion batteries. 相似文献
16.
Tomoya Uruga Mizuki Tada Oki Sekizawa Yasumasa Takagi Toshihiko Yokoyama Yasuhiro Iwasawa 《Chemical record (New York, N.Y.)》2019,19(7):1444-1456
We designed and constructed a beamline BL36XU at the 8 GeV synchrotron radiation facility SPring‐8 to provide information required for the development of next‐generation polymer electrolyte fuel cells (PEFCs) by clarifying the dynamic aspects of structures and electronic states of cathode catalysts under PEFC operating conditions and in the deterioration processes by accelerated durability test protcols. To investigate the mechanism and degradation process for the cathode electrocatalysis in practical PEFCs, we developed advanced time‐ and spatially‐resolved in‐situ/operando X‐ray absorption fine structure measurement systems and complementary analytical systems (X‐ray emission spectroscopy (XES), X‐ray diffraction (XRD), X‐ray computer tomography (CT) and hard X‐ray photoelectron spectroscopy (HAXPES)) and combined them to develop multi‐analytical systems at BL36XU. Multi‐analytical systems are very powerful for observing spatial‐temporal features of the transient processes occurring in complex systems such as PEFCs. This account describes the design, performance, and research results of the BL36XU and multi‐analytical in‐situ/operando systems. 相似文献
17.
Jinju Song Jihyeon Gim Sungjin Kim Jungwon Kang Dr. Vinod Mathew Dr. Docheon Ahn Prof. Jaekook Kim 《化学:亚洲杂志》2014,9(6):1550-1556
A nonstoichiometric sodium manganese oxide (NaxMnO2+δ) cathode useful for sodium batteries was synthesized by an ambient‐temperature strategy that involved facile reduction of aqueous sodium permanganate in sodium iodide and subsequent heat treatment at 600 °C. Combined powder X‐ray diffraction and synchrotron X‐ray diffraction analyses confirmed the annealed sample to belong to a NaxMnO2 phase with a P2‐hexagonal structure. The ICP‐AES results confirmed the stoichiometry of the sample to be Na0.53MnO2+δ. Electron microscopy studies revealed the particle size of the electrode to be in the range of a few hundred nanometers. The Na0.53MnO2+δ cathode delivered an average discharge capacity of 170 mA h g?1 with a stable plateau at 2.1 V for the initial 25 cycles versus sodium. Ex situ XANES studies confirmed the reversible intercalation of sodium into Na0.53MnO2+δ and suggested the accommodation of over‐stoichiometric Mn4+ ions to contribute towards the performance of the electrode. 相似文献
18.
Tianyi Song Wenjiao Yao Pinit Kiadkhunthod Yongping Zheng Nanzhong Wu Xiaolong Zhou Sarayut Tunmee Suchinda Sattayaporn Yongbing Tang 《Angewandte Chemie (International ed. in English)》2020,59(2):740-745
Sodium‐ion batteries (NIBs) are the most promising alternatives to lithium‐ion batteries in the development of renewable energy sources. The advancement of NIBs depends on the exploration of new electrode materials and fundamental understanding of working mechanisms. Herein, via experimental and simulation methods, we develop a mixed polyanionic compound, Na2Fe(C2O4)SO4?H2O, as a cathode for NIBs. Thanks to its rigid three dimensional framework and the combined inductive effects from oxalate and sulfate, it delivered reversible Na insertion/desertion at average discharging voltages of 3.5 and 3.1 V for 500 cycles with Coulombic efficiencies of ca. 99 %. In situ synchrotron X‐ray measurements and DFT calculations demonstrate the Fe2+/Fe3+ redox reactions contribute to electron compensation during Na+ desertion/insertion. The study suggests mixed polyanionic frameworks may provide promising materials for Na ion storage with the merits of low cost and environmental friendliness. 相似文献
19.
Three‐Dimensional Fe2N@C Microspheres Grown on Reduced Graphite Oxide for Lithium‐Ion Batteries and the Li Storage Mechanism
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Dr. Peng Yu Dr. Lei Wang Dr. Fanfei Sun Dr. Dongdong Zhao Dr. Chungui Tian Dr. Lu Zhao Xu Liu Prof. Jianqiang Wang Prof. Honggang Fu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3249-3256
Nanostructured iron compounds as lithium‐ion‐battery anode material have attracted considerable attention with respect to improved electrochemical energy storage and excellent specific capacity, so lots of iron‐based composites have been developed. Herein, a novel composite composed of three‐dimensional Fe2N@C microspheres grown on reduced graphite oxide (denoted as Fe2N@C‐RGO) has been synthesized through a simple and effective technique assisted by a hydrothermal and subsequent heating treatment process. As the anode material for lithium‐ion batteries, the synthetic Fe2N@C‐RGO displayed excellent Li+‐ion storage performance with a considerable initial capacity of 847 mAh g?1, a superior cycle stability (a specific discharge capacity of 760 mAh g?1 remained after the 100th cycle), and an improved rate‐capability performance compared with those of the pure Fe2N and Fe2N‐RGO nanostructures. The good performance should be attributed to the existence of RGO layers that can facilitate to enhance the conductivity and shorten the lithium‐ion diffusion path; in addition, the carbon layer on the surface of Fe2N can avert the structure decay caused by the volume change during the lithiation/delithiation process. Moreover, in situ X‐ray absorption fine‐structure analysis demonstrated that the excellent performance can be attributed to the lack of any obvious change in the coordination geometry of Fe2N@C‐RGO during the charge/discharge processes. 相似文献
20.
Heng Wang Shun Hamanaka Prof. Toshihiko Yokoyama Dr. Hirofumi Yoshikawa Prof. Kunio Awaga 《化学:亚洲杂志》2011,6(4):1074-1079
In situ X‐ray absorption fine structure (XAFS) analyses were performed on rechargeable molecular cluster batteries (MCBs), which were formed by a lithium anode and cathode‐active material, [Mn12O12(CH3CH2C(CH3)2COO)16(H2O)4] with tert‐pentyl carboxylate ligand (abbreviated as Mn12tPe), and with eight Mn3+ and four Mn4+ centers. This mixed valence cluster compound is used in an effort to develop a reusable in situ battery cell that is suitable for such long‐term performance tests. The Mn12tPe MCBs exhibit a large capacity of approximately 210 Ah kg−1 in the voltage range V=4.0–2.0 V. The X‐ray absorption near‐edge structure (XANES) spectra exhibit a systematic change during the charging/discharging with an isosbestic point at 6555 eV, which strongly suggests that only either the Mn3+ or Mn4+ ions in the Mn12 skeleton are involved in this battery reaction. The averaged manganese valence, determined from the absorption‐edge energy, decreased monotonically from 3.3 to 2.5 in the first half of the discharging (4.0>V>2.8 V), but changed little in the second half (2.8>V>2.0 V). The former valence change indicates a reduction of the initial [Mn12]0 state by approximately ten electrons, which corresponds well with the half value of the observed capacity. Therefore, the large capacity of the Mn12 MCBs can be understood as being due to a combination of the redox change of the manganese ions and presumably a capacitance effect. The extended X‐ray absorption fine structure (EXAFS) indicates a gradual increase of the Mn2+ sites in the first half of the discharging, which is consistent with the XANES spectra. It can be concluded that the Mn12tPe MCBs would include a solid‐state electrochemical reaction, mainly between the neutral state [Mn12]0 and the super‐reduced state [Mn12]8− that is obtained by a local reduction of the eight Mn3+ ions in Mn12 toward Mn2+ ions. 相似文献