Phosphorus-doped silicon nanorod anodes for high power lithium-ion batteries

• Chao Yan,
• Qianru Liu,
• Jianzhi Gao,
• Zhibo Yang and
• Deyan He

Beilstein J. Nanotechnol. 2017, 8, 222–228, doi:10.3762/bjnano.8.24

• Figure 4d. The current density for the test was set at 0.2 A/g to 20 A/g. The prepared Si anode delivered stable cycling performance under all test conditions. It is noteworthy that even under a current density as high as 20 A/g, the Si anode still presented a specific capacity of 380 mAh/g. The

• , the structure of the electrodes was stabilized under the test rates, and the activation started to play the leading role in the Si anode. Thus, the increased capacity after the 10th cycle could be ascribed to the activation of the anode. At the same time, it is noteworthy that the enormous specific

• capacity of Si will bring great changes regarding anode–cathode matching. For the practical application of Si-based anodes, the state-of-the-art commercial cathodes cannot deliver a suitable matching with the Si anode. Thus, the search for suitable cathodes should be of high priority for researchers of Si

Effect of nanostructured carbon coatings on the electrochemical performance of Li_1.4Ni_0.5Mn_0.5O_2+x-based cathode materials

• Konstantin A. Kurilenko,
• Oleg A. Shlyakhtin,
• Oleg A. Brylev,
• Dmitry I. Petukhov and
• Alexey V. Garshev

Beilstein J. Nanotechnol. 2016, 7, 1960–1970, doi:10.3762/bjnano.7.187

• lithium diffusion coefficient, a higher specific capacity and lower values of charge transfer resistance, which can be related to the more uniform carbon coatings and to the significant content of sp2-hybridized carbon detected by XPS and by Raman spectroscopy. Keywords: carbon coatings; electrode

• the cell polarization and the charge transfer resistance. This causes an increase of the specific capacity in comparison with pure Li1.4Ni0.5Mn0.5O2+x. Analyzing the CVA, EI and galvanostatic cycling data for LNM/C composites obtained using linear and cross-linked PVA, it can be seen that the presence

• content of sp2-hybridized carbon were obtained. The synergistic effect of these features of ultrathin carbon coatings results in higher values of the lithium diffusion coefficient and a lower charge-transfer resistance of the whole nanocomposite and, hence, to the enhancement of specific capacity of as

Microwave synthesis of high-quality and uniform 4 nm ZnFe₂O₄ nanocrystals for application in energy storage and nanomagnetics

• Christian Suchomski,
• Ben Breitung,
• Ralf Witte,
• Michael Knapp,
• Sondes Bauer,
• Tilo Baumbach,
• Christian Reitz and
• Torsten Brezesinski

Beilstein J. Nanotechnol. 2016, 7, 1350–1360, doi:10.3762/bjnano.7.126

• 10th cycle. We note that the first two (formation) cycles were performed at C/20 before increasing the C-rate. The specific capacity in the initial cycle was always in the range of (1270 ± 20) mAh/gZFO. The fact that this value exceeds the theoretical specific capacity of ZFO (qth = 1000.5 mAh/gZFO

• /gZFO at C/10, C/5 and C/2, respectively. Regardless of C-rate, they showed some kind of activation with a minimum in specific capacity between cycle number 50 and 80. Such behavior has been observed before for ZFO and other conversion-type anode materials [53][55][58]. The capacity degradation in the

• subsequent cycles – after the specific capacity had leveled off – was quite small (e.g., 0.017% per cycle at C/10). For the C/2 rate, even an increase in specific capacity by 20 mAh/gZFO was observed between the 50th and 500th cycle. After 500 cycles, the cell at C/10 rate was still capable of delivering an

Improved lithium-ion battery anode capacity with a network of easily fabricated spindle-like carbon nanofibers

• Mengting Liu,
• Wenhe Xie,
• Lili Gu,
• Tianfeng Qin,
• Xiaoyi Hou and
• Deyan He

Beilstein J. Nanotechnol. 2016, 7, 1289–1295, doi:10.3762/bjnano.7.120

• materials. Commercial graphite, with low specific capacity and poor rate capability, no longer meets the urgent requirements of modern technologies as an anode material for LIBs [4][5]. Hence, exploring new candidates with higher energy density and better cycling endurance becomes imperative. Presently

• , transition metal oxides are the focus of intensive efforts for LIB anode materials due to their remarkable specific capacity, low cost and environmental compatibility [6][7][8][9][10][11]. Manganese oxide (MnO) is a particularly good choice owing to its high theoretical specific capacity of 755 mAh g−1, low

• anodes. To further identify the cycling performance of the networked carbon anode anchored with MnO and N, a cell was cycled at a higher current density of 0.5 A g−1. As shown in Figure 3e, it delivers a reversible specific capacity of 591 mAh g−1 after 200 cycles with a considerable coulombic efficiency

Mesoporous hollow carbon spheres for lithium–sulfur batteries: distribution of sulfur and electrochemical performance

• Anika C. Juhl,
• Artur Schneider,
• Boris Ufer,
• Torsten Brezesinski,
• Jürgen Janek and
• Michael Fröba

Beilstein J. Nanotechnol. 2016, 7, 1229–1240, doi:10.3762/bjnano.7.114

• been subject of intensive research [1][2][3]. However, being limited by a theoretical specific capacity of the active materials of approximately 300 mAh·g−1, their storage capacity is not sufficient to serve as the primary energy source of domains such as long-range automotive transport [4][5]. Due to

• the high theoretical specific capacity (1675 mAh·g−1) and specific energy (2600 Wh·kg−1) of sulfur the lithium–sulfur (Li–S) battery is a promising candidate to overcome this limitation and, thus, replace the Li–ion system [4][6]. Besides, sulfur offers the advantages of being naturally abundant, non

• specific capacity (areal capacity) levels off at about 500 mAh·g−1 (1 mAh·cm−2) after 60 cycles, and the cell exhibits rather stable performance for 500 cycles with a fade rate of 0.06% per cycle (between the 2nd and 500th cycle at C/5). Also, the Coulombic efficiency stabilizes above 99.5%, thereby

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• supercapacitor electrodes [46]. Also the CNO/PEDOT:PSS composites, which were previously discussed, showed promising properties for the application as electrode material in supercapacitors, such as a specific capacity of 96 F·g−1, good cation-exchange properties and a simple synthesis [47]. In a recent study

• Co3O4 electrodes. They observed, for example, an increase of the specific capacity from 190 mA·h·g−1 to 632 mA·h·g−1 at a current density of 200 mA·g−1 and also an increased rate capability [64]. In the latter report, the CNO hybrid material was prepared from KMnO4 and CNOs by a hydrothermal method

• incorporation of CNOs. The specific capacity increased from 260 mA·h·g−1 to 630 mA·h·g−1, at a current density of 50 mA·g−1. In addition, the authors report an increased rate capability, stable cycling performance, and coulomb efficiency of nearly 100% [65]. Fuel cells: CNOs were also investigated as catalyst

Magnesium batteries: Current state of the art, issues and future perspectives

• Rana Mohtadi and
• Fuminori Mizuno

Beilstein J. Nanotechnol. 2014, 5, 1291–1311, doi:10.3762/bjnano.5.143

• mAh cm−3 for lithium. It may also provide an opportunity for battery cost reductions due to its natural abundance in the earth crust (5th most abundant element) [7][8]. More importantly, despite the fact that magnesium metal is not competitive with lithium metal on both specific capacity (2205 mAh g−1

• vs Mg using an organohalo-aluminate/tetrahydrofuran electrolyte. While the highest initial specific capacity at 1 C rate was reported for the Bi0.88Sb0.12 (298 mAh g−1), it dropped to 215 mAh g−1 after 100 cycles. The smallest capacity fade with cycling was observed for the Bi anode (pulverization

Thermal stability and reduction of iron oxide nanowires at moderate temperatures

• Annalisa Paolone,
• Marco Angelucci,
• Stefania Panero,
• Maria Grazia Betti and
• Carlo Mariani

Beilstein J. Nanotechnol. 2014, 5, 323–328, doi:10.3762/bjnano.5.36

• energy-density is leading to the development of nanostructured metal oxides [2][3][4], because the nanostructuring allows a high specific capacity [5][6][7][8][9][10][11][12][13]. These considerations brought the development of a new variety of transition metal oxide based systems [14][15][16][17][18][19

Synthesis and electrochemical performance of Li₂Co_1−xM_xPO₄F (M = Fe, Mn) cathode materials

• Nellie R. Khasanova,
• Oleg A. Drozhzhin,
• Stanislav S. Fedotov,
• Darya A. Storozhilova,
• Rodion V. Panin and
• Evgeny V. Antipov

Beilstein J. Nanotechnol. 2013, 4, 860–867, doi:10.3762/bjnano.4.97

• materials that operate at high voltages, and/or by increasing the specific capacity with materials that could cycle more than one Li atom per active transition metal atom. In this respect, fluorophosphates of the general formula A2MPO4F seem to be very attractive since they are expected to exhibit a high

Influence of particle size and fluorination ratio of CF_x precursor compounds on the electrochemical performance of C–FeF₂ nanocomposites for reversible lithium storage

• Ben Breitung,
• M. Anji Reddy,
• Venkata Sai Kiran Chakravadhanula,
• Michael Engel,
• Christian Kübel,
• Annie K. Powell,
• Horst Hahn and
• Maximilian Fichtner

Beilstein J. Nanotechnol. 2013, 4, 705–713, doi:10.3762/bjnano.4.80

• iron nanoparticles in the carbon matrix, their specific capacity was about 250 mAh/g, which is only one third of the theoretical value. To improve the capacity and to still benefit from a stabilizing and tightly attached carbon matrix, a new solid-state chemical synthesis, which is based on a reaction

• materials were ball-milled at 300 rpm for 2 h as this was the best milling condition we could find with respect to the electrochemical performance. Other milling conditions were tested for all materials, but the obtained products showed the best cycling stability and specific capacity when ball-milled with

A facile synthesis of a carbon-encapsulated Fe₃O₄ nanocomposite and its performance as anode in lithium-ion batteries

• Raju Prakash,
• Katharina Fanselau,
• Shuhua Ren,
• Tapan Kumar Mandal,
• Christian Kübel,
• Horst Hahn and
• Maximilian Fichtner

Beilstein J. Nanotechnol. 2013, 4, 699–704, doi:10.3762/bjnano.4.79

• specific capacity of Fe3O4 is 926 mAh·g−1, which is far beyond that of a graphite anode (372 mAh·g−1). However, because of agglomerations and the significant volume change of active materials during the redox reaction, Fe3O4 anodes have suffered greatly from poor cyclic performances. A variety of

Electrochemical and electron microscopic characterization of Super-P based cathodes for Li–O₂ batteries

• Mario Marinaro,
• Santhana K. Eswara Moorthy,
• Jörg Bernhard,
• Ludwig Jörissen,
• Margret Wohlfahrt-Mehrens and
• Ute Kaiser

Beilstein J. Nanotechnol. 2013, 4, 665–670, doi:10.3762/bjnano.4.74

• Figure 1. The cell was cycled following a time-limited constant-current protocol. A current of 50 mA·(g carbon)−1 was applied for 10 h leading to a final specific capacity of 500 mAh·(g carbon)−1. At the expense of some energy density, the use of such protocol ensures good cyclability (more than 30

A facile approach to nanoarchitectured three-dimensional graphene-based Li–Mn–O composite as high-power cathodes for Li-ion batteries

• Wenyu Zhang,
• Yi Zeng,
• Chen Xu,
• Ni Xiao,
• Yiben Gao,
• Lain-Jong Li,
• Xiaodong Chen,
• Huey Hoon Hng and
• Qingyu Yan

Beilstein J. Nanotechnol. 2012, 3, 513–523, doi:10.3762/bjnano.3.59

• processes. The optimized cathode delivers a stable specific capacity of ~84 mAh·g−1 during the 500th cycle at a gravimetric current density of 5625 mA·g−1 (~38.01 C) with a voltage window of 3–4.5 V, which corresponds to a specific power density of 100 kW·kg−1 and a specific energy density of 278 Wh·kg−1

• ). The LMO/G (ILMO:G = 1.22) electrode depicts a specific capacity of 170 mAh·g−1 during the second cycle, which remains at 93 mAh·g−1 during the 300th cycle. Based on the voltage profiles under such cycling conditions, the corresponding energy density and power density were calculated to be 284 Wh·kg−1

• 5625 mA·g−1 (38.01 C) discharge rates. The specific capacity was calculated based on the mass of active material. The Nyquist plots of LiMn2O4/graphene and pure LiMn2O4 electrodes at the fifth fully discharged state. (a) The second-cycle discharge voltage profiles of LiMn2O4/graphene (ILMO:G = 1.22