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991.
Yuxin Liu Prof. Ping Liu Prof. Dongqing Wu Yanshan Huang Yanping Tang Prof. Yuezeng Su Prof. Fan Zhang Prof. Xinliang Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5617-5622
Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron‐doped, carbon‐coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core–shell architecture and B‐doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium‐ion batteries with a highly stable capacity of 1165 mA h g?1 at 0.1 A g?1 after 360 cycles and an excellent rate capability of 600 mA h g?1 at 3.2 A g?1, and thus outperforms most of the previously reported SnO2‐based anode materials. 相似文献
992.
Martin Pumera 《Chemical record (New York, N.Y.)》2009,9(4):211-223
Graphene is a new 2D nanomaterial with outstanding material, physical, chemical, and electrochemical properties. In this review, we first discuss the methods of preparing graphene sheets and their chemistry. Following that, the fundamental reasons governing the electrochemistry of graphene are meaningfully described. Graphene is an excellent electrode material with the advantages of conductivity and electrochemistry of sp2 carbon but without the disadvantages related to carbon nanotubes, such as residual metallic impurities. We highlight important applications of graphene and graphene nanoplatelets for sensing, biosensing, and energy storage. © 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 9: 211–223; 2009: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.200900008 相似文献
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996.
Dao-Sheng Liu Feng Jin Dr. Aijian Huang Dr. Xiaoli Sun Hao Su Dr. Yang Yang Dr. Yufei Zhang Dr. Xianhong Rui Dr. Hongbo Geng Prof. Cheng Chao Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(65):14881-14889
Sodium-ion batteries have attracted interest as an alternative to lithium-ion batteries because of the abundance and cost effectiveness of sodium. However, suitable anode materials with high-rate and stable cycling performance are still needed to promote their practical application. Herein, three-dimensional Na2Ti3O7 nanowire arrays with enriched surface vacancies endowed by phosphorus doping are reported. As anodes for sodium-ion batteries, they deliver a high specific capacity of 290 mA h g−1at 0.2 C, good rate capability (50 mA h g−1at 20 C), and stable cycling capability (98 % capacity retention over 3100 cycles at 20 C). The superior electrochemical performance is attributed to the synergistic effects of the nanowire arrays and phosphorus doping. The rational structure can provide convenient channels to facilitate ion/electron transport and improve the capacitive contributions. Moreover, the phosphorus-doping-induced surface vacancies not only provide more active sites but also improve the intrinsic electrical conductivity of Na2Ti3O7, which will enable electrode materials with excellent sodium storage performance. This work may provide an effective strategy for the synthesis of other anode materials with fast electrochemical reaction kinetics and good sodium storage performance. 相似文献
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998.
We explore the disproportionation reaction of superoxide anions in the presence of H+ and Li+ cations with high quality multiconfigurational ab-initio methods. This reaction is of paramount importance in Li−O2 battery chemistry as it represents the source of a major degrading impurity, singlet molecular oxygen. For the first time, the thermodynamic and kinetic data of the reaction are drawn from an accurate theoretical model where the electronic structure of the reactant and products is treated at the necessary level of theory. Overall, the H+ catalyzed O2−+O2− disproportionation follows a very efficient thermodynamic and kinetic reaction path leading to neutral 3O2, 1O2 and peroxide anions. On the contrary, we have found that the Li+ catalysis promotes only the release of 3O2 whereas the 1O2 formation is energetically unfeasible at room temperature. 相似文献
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1000.
Lu Xiao Tao Zhou Jia Meng 《Particuology》2009,7(6):491-495
Nanocrystalline Mn-Zn ferrites (Mno.GZno.4Fe204) with particle size of 12 nm were synthesized hydrotherreally using spent alkaline Zn-Mn batteries, and accompanied by a study of the influencing factors. The nanocrystals were examined by powder X-ray diffraction (XRD) for crystalline phase identification, and scanning electron microscopy (SEM) for grain morphology. The relationship between concentration of Fe(II), Mn(II), and Zn(II) and pH value was obtained through thermodynamic analysis of the Fe(II)-Mn(II)-Zn(II)-NaOH-H2O system. The results showed that all ions were precipitated completely at a pH value of 10-11. The optimal preparation conditions are: co-precipitation pH of 10.5, temperature of 200 ℃ and time of 9 h. 相似文献