ADVANCED SYNTHESIS & CATALYSIS
·
2017
·Vol. 359
·期 13
·2215-2221
·
IF 5.646
Wenhui Zhu,Yingcai Ding,Zhaogang Bian,Ping Xie,Baojun Xu,Qiujie Tang,Wei Wu,Aihua Zhou
Sulfenylation is an important transformation to generate C−S bonds in organic synthesis. Here, two three-component synthetic protocols have been developed by using imidazo[1,2- a ]pyridine, inorganic, odorless S 8 and alcohols or arylboronic acids as reactants to make alkylthio-/arylthio-substituted imidazo[1,2- a ]pyridine derivatives via C( sp 2 )–H functionalization. The reactions proceeded with high efficiency and broad functional group tolerance, affording the products regioselectively and in good yields.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 23
·8683-8689
·
IF 0
Zhubing Xiao,Zhi Yang,Huagui Nie,Yanqi Lu,Keqin Yang,Shaoming Huang
The current investigation of lithium–sulfur (Li–S) batteries faces three practical problems: (1) the poor conductivity of sulfur; (2) the notorious shuttle mechanism; and (3) the volume variation of the sulfur cathode. In principle, carbon nanotubes (CNTs) have a strong potential for improving sulfur usage because of their high electrical conductivity. Furthermore, opening holes in CNTs or creating pores on the walls is also a useful approach to not only enhance the diffusion of Li ions, but also enable more sulfur to fill the interior of the CNTs, which would be beneficial in retaining the soluble poly-sulfide intermediates and accommodate volume variations. Herein, we designed a mild one-step oxidation approach to create porous CNTs (PCNTs) through a chemical reaction between CNTs and rare oxygen sourced from a nebulized water stream at high temperatures. The higher specific surface area and pore volume values confirmed that PCNTs had significant porosity, compared with raw CNTs. When the PCNTs–S composites were tested as cathode materials in Li–S batteries, the cathode with 78 wt% S content exhibited an initial reversible capacity of 1382 mA h g−1 at 0.2 C. Furthermore, a reversible capacity of 150 mA h g−1 can be preserved, even at a very high current rate of 15 C. More importantly, it is also confirmed that a cathode with 89 wt% S content unexpectedly delivered a reversible capacity as high as 1165 mA h g−1sulfur/830 mA h g−1electrode at the initial cycle, and 792 mA h g−1sulfur/564 mA h g−1electrode after 200 cycles at a current rate of 0.2 C. To the best of our knowledge, such a high rate performance (15 C) and S loading (89 wt%) in cathodes of advanced Li–S batteries have been infrequently reported in previous research.
研究领域:
电化学储能
·
材料科学
·
纳米能源材料
·
先进电池技术
·
能源化学
✓ 已验证
DOI
Nano Energy
·
2017
·
IF 12.343
Qizhen Zhu,Qian Zhao,Yabin An,Babak Anasori,Haoran Wang,Bin Xu
Lithium-sulfur (Li-S) batteries are one of the most promising energy storage systems with high energy density . However, they suffer from fast capacity fading due to the shuttle of the dissolved polysulfides . Using small sulfur molecules (S 2–4 ) as cathodes can avoid the shuttle problem, but the preparation of ultra-microporous carbon to encapsulate S 2–4 is challenging. Here, we report a Li-S battery with an excellent cycling performance by using a unique ultra-microporous carbon (UMC) with a uniform pore size of 0.55 nm. The UMC was synthesized from PVDF via a facile pyrolysis process to only accommodate small S 2–4 molecules and eliminate large S 8 molecules. This S/UMC composite electrode is compatible with the carbonate-based electrolyte used in Li-S batteries. The resulting battery shows a typical discharging profile with only one long potential plateau because the reductions from cyclo-S 8 to dissolved polysulfides and consequence shuttle problem are avoided. The S/UMC composite retains a capacity of about 852 mAh g −1 and Coulombic efficiency approaching 100% after 150 cycles at 0.1 C and delivers a long-term cycling at 1 C for 1000 cycles with only around 0.03% capacity loss per cycle. We also tested this S/UMC composite electrode in Na-S systems and observed similar electrochemical behaviour. These results indicate that the S/UMC composite is a promising candidate as an electrode material in Li-S and Na-S batteries and related systems.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2018
·Vol. 5
·期 12
·1591-1598
·
IF 4.446
Yongguang Zhang,Jun Ren,Daorui Wang,Chengwei Zhang,Fuxing Yin,Aliya Mukanova,Zhumabay Bakenov
A novel three-dimensionally (3D) ordered mesoporous polypyrrole (OMPPy) is successfully synthesized through a facile chemical polymerization using silica nanosphere arrays as hard templates. The resulting OMPPy possesses a large BET surface area (270.9 m 2 g −1 ), 3D interconnected large mesopores (∼32 nm), and small mesopores (2-4 nm) on the large mesopore walls. The OMPPy is then applied as a host to form a kind of sulfur/OMPPy (S/OMPPy) composite cathode through a solution method followed by a heat-treatment process. Electrochemical test results show that the developed S/OMPPy cathode containing 51.1 wt% sulfur is able to deliver a high and stable specific discharge capacity of 908 mAh g −1 at 0.1C after 100 cycles. At higher discharge rates of 1C, the S/OMPPy exhibits a discharge capacity of 673.7 mAh g −1 after 100 cycles and 462.2 mAh g −1 after 300 cycles. The exceptional electrochemical performance of the S/OMPPy is attributed to the large surface area and the commendable pore size distribution of OMPPy for trapping polysulfides as well as the ordered large mesopores for excellent electrolyte accessibility and fast Li-ion transport. Graphical A 3D boost for charging performance : Cathode materials for Li−S batteries are prepared by loading sulfur onto three dimensionally ordered mesoporous polypyrrole as support. The composites exhibit a high specific capacity as well as a stable cycling performance, demonstrating the promising potential for an application in Li−S batteries.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
Advanced Science
·
2018
·Vol. 5
·期 7
·1800026
·
IF 12.441
Zeqing Guo,Huagui Nie,Zhi Yang,Wuxing Hua,Chunping Ruan,Dan Chan,Mengzhan Ge,Xi'an Chen,Shaoming Huang
Lithium–sulfur batteries suffer from poor cycling stability at high areal sulfur loadings (ASLs) mainly because of the infamous shuttle problem and the increasing diffusion distance for ions to diffuse along the vertical direction of the cathode plane. Here, a carbon nanotube (CNT)/graphene (Gra)-S-Al 3 Ni 2 cathode with 3D network structure is designed and prepared. The 3D network configuration and the Al in the Al 3 Ni 2 provide an efficient channel for fast electron and ion transfer in the three dimensions, especially along the vertical direction of the cathode. The introduction of Ni in the Al 3 Ni 2 is able to suppress the shuttle effect via accelerating reaction kinetics of lithium polysulfide species conversion reactions. The CNT/Gra-S-Al 3 Ni 2 cathode exhibits ultrahigh cycle-ability at 1 C over 800 cycles, with a capacity degradation rate of 0.055% per cycle. Additionally, having high ASLs of 3.3 mg cm −2 , the electrode delivers a high reversible areal capacity of 2.05 mA h cm −2 (622 mA h g −1 ) over 200 cycles at a higher current density of 2.76 mA cm −2 with high capacity retention of 85.9%. The outstanding discharge performance indicates that the design offers a promising avenue to develop long-life cycle and high-sulfur-loading Li–S batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Jun Wu,Ji Hu,Kaixin Song,Junming Xu,Huifang Gao
Spirulina was used for the first time as a raw nitrogen-doped porous carbon source to synthesize carbon/sulphur (carbon/S) composite cathodes for lithium-sulphur batteries. The composites consisting of sulphur and spirulina-derived carbon with micro- and meso-pores showed an obvious carbon encapsulating sulphur structure. The carbon/S cathodes exhibited much better electrochemical performance than pristine sulphur, delivering an initial discharge capacity of 662 mAh g −1 with nearly 60% capacity retention after 100 cycles at 1 C current density (1670 mA g −1 ). The improved electrochemical stability of the composites can be ascribed to the synergistic effects between the encapsulation of sulphur by spirulina-derived carbon and adsorption of polysulfides on N doped carbon lattice. These effects successfully prevented or retarded the shuttle effect of sulphur cathodes.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
功能碳材料
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2023
·
IF 6
Zhihao Shen,Shuming Wen,Yongchao Miao,Han Wang,Qicheng Feng
Unavoidable metal ions commonly exist in the pulp during flotation. These ions can affect the floatability of minerals, and they can also result in the differences in the surface features between different minerals. In this study, how Fe 3+ affected the flotation behavior of cerussite was investigated by micro-flotation tests. The corresponding adsorption characteristics of the sulfidizing agent and collector on the surfaces of cerussite were investigated by surface-analysis techniques. The results of micro-flotation tests showed that the floatability of cerussite significantly decreased when Fe 3+ was added before Na 2 S and xanthate. The flotation recovery of cerussite decreased compared with that obtained without participation of Fe 3+ . Additionally, the results of xanthate and Na 2 S adsorption tests, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and zeta potential measurements verified that Fe 3+ and its hydrophilic hydroxyl derivatives (Fe-OH compounds) resulted in reduced amounts and reactive activities of S-bearing species adsorbed on the surfaces of cerussite. This decreased the adsorption capacity of subsequently added xanthate, resulting in the difficulty in effectively recovering cerussite in the sulfidization-xanthate system.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
DOI
高影响因子
IONICS
·
2022
·Vol. 28
·期 3
·1473-1481
·
IF 2.961
Huang Xiaona,Ren Yaqi,Long Jianping,Lin Jinhui,Zhou Zheng
The interface between carbon matrix and sulfur (S) is critically essential for the exhaustive conversion of S to lithium sulfide (Li 2 S). However, the struggling diffusion of lithium (Li) ions on the surface of carbon allows severe polarization of Li ions and shuttling of polysulfides. Herein, we demonstrate an effective strategy via decreasing the diffusion barrier of Li ions on the conductive carbon matrix surface via embedding Fe and N atoms within the carbon matrix. As combined with 80% sulfur content, the proposed interfaces exhibit an excellent increment in both of specific capacity and stability cycles. The promoted mechanism at the proposed interface is clearly evaluated by density functional theory (DFT) calculation, cyclic voltammograms (CV) curve, and AC impedance. This research offers a novel inspires to design fast conversion of high content S cathode via promoting the Li-ion diffusion within the cathode.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Wenli Wei,Jinmei Li,Qi Wang,Dong Liu,Jingye Niu,Peng Liu
Conductive supports could improve the electrical conductivity of the electrode in lithium–sulfur (Li–S) batteries but suffer from the shuttle effect originated from the polysulfide dissolution, while the hydrophilic metal oxides could avoid the shuttle effect but with poor conductivity. Herein, a facile approach was developed to fabricate hierarchically porous tin oxide (SnO2) nanoparticle-anchored tubular polypyrrole (T-PPy) as a sulfur host, in order to integrate the advantages of conductive supports and metal oxides but overcome their shortcomings. In the unique structure, the T-PPy nanotubes acted as a conductive network to not only improve the electrical conductivity of cathodes but also accommodate the volume expansion of the sulfur cathode during cycling as well as relatively confine the polysulfide diffusion, while the SnO2 nanoparticles served as a high-efficient polysulfide trap to mitigate the shuttle effect due to the chemical bond between SnO2 and polysulfides. Moreover, the hierarchically porous structure and therefore large surface area of the proposed S/(T-PPy)@SnO2 cathode were favorable for the accommodation of sulfur and lithium sulfides. Consequently, S/(T-PPy)@SnO2 with 64.7% sulfur mass content exhibited excellent cyclic stability with a decay rate of only 0.05% per cycle along with 500 cycles at 1 C, rate capability of 383.7 mA h/g at 5 C, and Coulombic efficiency above 90%, outstanding among most of the reported PPy-based sulfur cathodes and PPy-based ternary sulfur cathodes.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 35
·18358-18366
·
IF 11.301
Chao Yue Zhang,Guo Wen Sun,Yun Fei Bai,Zhe Dai,Yi Rong Zhao,Xiu Ping Gao,Geng Zhi Sun,Xiao Bo Pan,Xiao Jun Pan,Jin Yuan Zhou
Vanadium sulfides, such as VS2, have been often used as sulfur host materials for lithium–sulfur batteries (LSBs), however, their high-symmetry and layered crystalline structure often lead to a poor rate-capability and a limited cycling stability of the resultant LSBs. Thus, in this work, a type of distorted NiAs-type structured V2S3 phase was designed and attempted to use it as a sulfur host for LSBs. The results showed that the prepared V2S3-nanocrystal decorated carbon nanofiber (CNF@V2S3) electrode films are freestanding, highly conductive and flexible. And the resultant CNF@V2S3/S cathodes show a high specific capacity (1169 mA h g−1 at 0.1C), an excellent rate capability (retain 78.9% at 2.0C), an ultra-low delay rate per cycle of 0.0071%, and a low self-discharge rate of 3.65% per month. A series of analyses indicate that these high electrochemical performances are mainly due to the high polarity, high conductivity and high catalytic activity of V2S3 nanocrystals, as well as the improved diffusivities of Li ions. This research could provide some new insight into the design of sulfur host materials for high-performance LSBs.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Jiahao Cheng,Wenlin Feng,Xiaozhan Yang,Cuicui Yang,Gang Zhang,Zhiying Liu
Bi 2 S 3 with a 2D van der Waals structure has attracted much attention due to its high conductivity, large absorption coefficient, and environmental friendliness. The preparation of tunable optoelectronic devices can be realized by exploiting and tuning Bi 2 S 3 intrinsic defects. In this work, a simple and rapid method for the preparation of bismuth sulfide thin films and successfully prepare Bi 2 S 3 with sulfur vacancies (S vac ) (LA-Bi 2 S 3 ) and oxygen passivated (S vac ) (AP-Bi 2 S 3 ) was presented. The defect state difference of the two devices leads to exhibit different optoelectronic properties. Under 638 nm and 1310 nm illuminations, the LA-Bi 2 S 3 photodetectors exhibit responsivities of up to 2250 and 3.6 mA/W and detectivities of 1.69 × 10 12 and 2.6 × 10 9 cm·Hz 1/2 W −1 , while the AP-Bi 2 S 3 photodetectors have ultra-fast on/off speeds of 1 ms and 8 ms, and on/off ratio up to 3 × 10 3 . The preparation method of the tunable optoelectronic devices gives a new avenue for defect tuning in metal sulfides and for the preparation and application of optoelectronic devices.
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Hangyu Gu,Rong Zhang,Ping Wang,Sanmu Xie,Chunming Niu,Hongkang Wang
In order to suppress the shuttling of soluble lithium polysulfides in Li-S batteries and increase the conductivity of the sulfur cathode, here we report the design and synthesis of three-dimensional (3D) highly ordered porous carbon bulk network (PCBNs), using silica (SiO 2 ) nanospheres as removable hard templates and soluble starch as carbon source. After carbonization and template removal, the as-prepared PCBNs composed of interconnected hollow carbon balls exhibit large surface area (447.4 m 2 /g) and large pore volume (1.567 cm 3 /g), high graphitization degree and robust framework. Serving as an efficient sulfur host, PCBNs supported sulfur cathode (S@PCBNs with sulfur content of 72 wt%) delivers a high discharge capacity of 760 mA h/g after 150 cycles at 0.1 C and 455 mA h/g after 400 cycles at 1 C. The superior lithium storage properties is attributed to the novel hierarchical microstructure of the PCBNs, in which the large hollow space not only allows high loading of sulfur but also efficiently accommodates the large volumetric expansion. Moreover, the interconnected PCBNs with high conductivity can spatially confine the shuttling of soluble polysulfides and enhance the redox reaction kinetics.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）