Unique two-dimensional(2D)porous nanosheets with overwhelmingly rich channels and large specific surface area exhibit superior electrochemical capacitance performance,as compared to the conventional zero-and one-dimen...Unique two-dimensional(2D)porous nanosheets with overwhelmingly rich channels and large specific surface area exhibit superior electrochemical capacitance performance,as compared to the conventional zero-and one-dimensional counterparts.As ternary transition metal sulfides(TMSs)are well recognized for their high electrochemical activity and capacity,and the replacement of oxygen with sulfur may result in high stability and flexible properties of the nanomaterials,as compared to transition metal oxides,herein we report the synthesis of 2D porous nanosheet arrays of Zn_(x)Co_(1-x)S(x=0,0.25,0.5,0.75,and 1)via a facile hydrothermal process.Due to the synergistic effect of the metal components and a unique 2D porous structure,the Zn_(0.5)Co_(0.5)S electrode was found to stand out as the best among the series,with a high specific capacity of 614 C g^(-1)at 1 A g^(-1)and excellent cycle retention rate of 90%over 10,000 cycles at 10 A g^(-1).Notably,a supercapattery based on a Zn_(0.5)Co_(0.5)S positive electrode and an activated carbon(AC)negative electrode(Zn_(0.5)Co_(0.5)S//AC)was found to display a 1.6 V voltage window,a 61 mA h g^(-1)specific capacity at 1 A g^(-1),a 49 Wh kg^(-1)energy density at 957 W kg^(-1)power density,and excellent cycling performance(88%over 10,000 cycles),suggesting tremendous potential of Zn_(0.5)Co_(0.5)S in the development of high-performance supercapattery devices.展开更多
The assembly of metal ions Zn2＋, Co2＋ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12（E2Ge2O3） （1, E = -CH2CH2COO-）. T...The assembly of metal ions Zn2＋, Co2＋ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12（E2Ge2O3） （1, E = -CH2CH2COO-）. The structure was determined by single-crystal X-ray diffraction and further characterized by IR spectroscopy, elemental analysis, energy- dispersive X-ray analysis, inductively coupled plasma, powder X-ray diffraction, thermogra- vimetric analysis and fluorescence spectroscopy. Compound 1 crystallizes in the chiral space group P212121, with a = 4.9096（5）, b = 8.9031（11）, c = 24.046（3） A, V = 1051.0（2） A3, C6H8Ge2O7Zn0.88Co0.12, Mr = 401.88, Z = 4, Dc = 2.540 g.cm-1,μ = 7.875 mm-1, F（000） = 775, GOF= 1.016, the final R = 0.0324 and wR = 0.0642. The structure ofl is built up by Ge-O sheets with Ge6 rings and Zn/Co-carboxyl layers. It should be mentioned that although the whole E2Ge2O32- ligand exhibits only one kind of coordination mode, it plays two roles in forming the structure： SBU and linker. In this situation, the E group of H2E2Ge2O3 ligand becomes a determining factor for structural dimensionality. In addition, it displays blue-violet emission light and shows high thermostability.展开更多
Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt s...Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt substituted perfluorosulfonic acid/polytetrafluoroethylene copolymer and dicyandiamide as the pyrolysis precursor to synthesize nitrogen-doped carbon nanotube(N–CNT) encapsulating cobalt nanoparticles hybrid material. The carbon layers and specific surface area of N–CNT have a critical role to the ORR performance due to the exposed active sites, determined by the mass ratio of the two precursors. The optimum hybrid material exhibits high ORR activity and stability, as well as excellent performance and durability in zinc–air battery.展开更多
The process of cobalt removal from zinc sulphate solution using rude antimony trioxide as an additive was investigated. The rude antimony trioxide was produced in treatment of copper and lead anode mud and its main co...The process of cobalt removal from zinc sulphate solution using rude antimony trioxide as an additive was investigated. The rude antimony trioxide was produced in treatment of copper and lead anode mud and its main components are antimony trioxide, antimony arsenate and lead antimonate. Using the rude antimony trioxide as the additive of cobalt removal can not only decrease operation cost of purification but also find out a new way for utilization of the rude antimony trioxide. The effects of temperature, dosage of zinc dust, the rude antimony trioxide, copper ion and solution pH on removal of cobalt were studied. And experimental data using the rude Sb 2O 3 as additive were compared with those using Sb 2O 3. The results indicate that using rude Sb 2O 3 as additive, cobalt concentration in solution could be decreased from 24 mg/L to below 1 mg/L under about the same conditions as using Sb 2O 3.展开更多
For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that ...For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that development of effects of aspirin resembles that of acetylsalicylate zinc. Acetylsalicylate cobalt at extremely low doses zone showed the highest antidepressant activity, demonstrating toxicity at high doses. Generally, it is revealed that the use of aspirin and its salts at high doses range causes maximum psychotropic effects development, usually accompanied by side-effects. Therefore, aspirin, acetylsalicylate cobalt and zinc at extremely low doses are recommended for further study as psychotropic medications.展开更多
镍钴氢氧化物由于理论比容量高、经济效益良好、来源广泛等优点,被广泛应用于镍锌电池中作为电极材料。本工作采用共沉淀法,调控具有不同镍钴比例的硝酸盐溶液,在室温环境下一步合成镍钴双金属氢氧化物,并将其制备成镍锌电池正极材料。...镍钴氢氧化物由于理论比容量高、经济效益良好、来源广泛等优点,被广泛应用于镍锌电池中作为电极材料。本工作采用共沉淀法,调控具有不同镍钴比例的硝酸盐溶液,在室温环境下一步合成镍钴双金属氢氧化物,并将其制备成镍锌电池正极材料。采用X射线衍射仪(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)等对所合成的样品进行表征,观察其微观形貌结构,采用电化学工作站等研究其作为镍锌电池电极材料的电化学性能。研究发现,采用高浓度Na OH溶液作为电解液,比其他通过共沉淀法所制备的镍钴氢氧化物在镍锌电池中所表现出的容量更高。结果表明,当镍钴投料比为4∶1时,样品具有最为出色的容量表现,其中,Ni_(4)Co_(1)-LDH样品在电流密度为0.5 A/g时容量可以达到327.9 m Ah/g。将其作为正极材料、锌箔作为负极,与高浓度的Na OH溶液一起组装成镍锌电池进行电化学测试,在0.5 A/g电流密度下具有230.7 m Ah/g的容量,该研究兼具材料合成快速和性能表现良好等优点,研究结果有望为镍锌电池性能优化提供新思路。展开更多
基金financial support from the National Natural Science Foundation of China(Nos.21101176 and 21676036)the Fundamental Research Funds for the Central Universities of Chongqing University(Nos.2018CDQYCH0028,2018CDXYHG0028 and 2019CDXYHG0013)+1 种基金the Graduate Research and Innovation Foundation of Chongqing(No.CYS-20040)the Large-scale Equipment Sharing Fund of Chongqing University(Nos.201903150149 and 202003150020)。
文摘Unique two-dimensional(2D)porous nanosheets with overwhelmingly rich channels and large specific surface area exhibit superior electrochemical capacitance performance,as compared to the conventional zero-and one-dimensional counterparts.As ternary transition metal sulfides(TMSs)are well recognized for their high electrochemical activity and capacity,and the replacement of oxygen with sulfur may result in high stability and flexible properties of the nanomaterials,as compared to transition metal oxides,herein we report the synthesis of 2D porous nanosheet arrays of Zn_(x)Co_(1-x)S(x=0,0.25,0.5,0.75,and 1)via a facile hydrothermal process.Due to the synergistic effect of the metal components and a unique 2D porous structure,the Zn_(0.5)Co_(0.5)S electrode was found to stand out as the best among the series,with a high specific capacity of 614 C g^(-1)at 1 A g^(-1)and excellent cycle retention rate of 90%over 10,000 cycles at 10 A g^(-1).Notably,a supercapattery based on a Zn_(0.5)Co_(0.5)S positive electrode and an activated carbon(AC)negative electrode(Zn_(0.5)Co_(0.5)S//AC)was found to display a 1.6 V voltage window,a 61 mA h g^(-1)specific capacity at 1 A g^(-1),a 49 Wh kg^(-1)energy density at 957 W kg^(-1)power density,and excellent cycling performance(88%over 10,000 cycles),suggesting tremendous potential of Zn_(0.5)Co_(0.5)S in the development of high-performance supercapattery devices.
基金supported by the Natural Science Fund for Young Scholars of Fujian Province(No. 2011J05018)the Fund for Young Scholars from Fujian Agriculture and Forestry University (No. 2011xjj06)
文摘The assembly of metal ions Zn2＋, Co2＋ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12（E2Ge2O3） （1, E = -CH2CH2COO-）. The structure was determined by single-crystal X-ray diffraction and further characterized by IR spectroscopy, elemental analysis, energy- dispersive X-ray analysis, inductively coupled plasma, powder X-ray diffraction, thermogra- vimetric analysis and fluorescence spectroscopy. Compound 1 crystallizes in the chiral space group P212121, with a = 4.9096（5）, b = 8.9031（11）, c = 24.046（3） A, V = 1051.0（2） A3, C6H8Ge2O7Zn0.88Co0.12, Mr = 401.88, Z = 4, Dc = 2.540 g.cm-1,μ = 7.875 mm-1, F（000） = 775, GOF= 1.016, the final R = 0.0324 and wR = 0.0642. The structure ofl is built up by Ge-O sheets with Ge6 rings and Zn/Co-carboxyl layers. It should be mentioned that although the whole E2Ge2O32- ligand exhibits only one kind of coordination mode, it plays two roles in forming the structure： SBU and linker. In this situation, the E group of H2E2Ge2O3 ligand becomes a determining factor for structural dimensionality. In addition, it displays blue-violet emission light and shows high thermostability.
基金financial support from the Ministry of Science and Technology of China(Grants 2016YFB0600901 and 2013CB933100)the National Natural Science Foundation of China(Grants 21573222 and 91545202)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB17020200)financial support from CAS Youth Innovation Promotion(Grant No.2015145)
文摘Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt substituted perfluorosulfonic acid/polytetrafluoroethylene copolymer and dicyandiamide as the pyrolysis precursor to synthesize nitrogen-doped carbon nanotube(N–CNT) encapsulating cobalt nanoparticles hybrid material. The carbon layers and specific surface area of N–CNT have a critical role to the ORR performance due to the exposed active sites, determined by the mass ratio of the two precursors. The optimum hybrid material exhibits high ORR activity and stability, as well as excellent performance and durability in zinc–air battery.
文摘The process of cobalt removal from zinc sulphate solution using rude antimony trioxide as an additive was investigated. The rude antimony trioxide was produced in treatment of copper and lead anode mud and its main components are antimony trioxide, antimony arsenate and lead antimonate. Using the rude antimony trioxide as the additive of cobalt removal can not only decrease operation cost of purification but also find out a new way for utilization of the rude antimony trioxide. The effects of temperature, dosage of zinc dust, the rude antimony trioxide, copper ion and solution pH on removal of cobalt were studied. And experimental data using the rude Sb 2O 3 as additive were compared with those using Sb 2O 3. The results indicate that using rude Sb 2O 3 as additive, cobalt concentration in solution could be decreased from 24 mg/L to below 1 mg/L under about the same conditions as using Sb 2O 3.
文摘For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that development of effects of aspirin resembles that of acetylsalicylate zinc. Acetylsalicylate cobalt at extremely low doses zone showed the highest antidepressant activity, demonstrating toxicity at high doses. Generally, it is revealed that the use of aspirin and its salts at high doses range causes maximum psychotropic effects development, usually accompanied by side-effects. Therefore, aspirin, acetylsalicylate cobalt and zinc at extremely low doses are recommended for further study as psychotropic medications.
文摘镍钴氢氧化物由于理论比容量高、经济效益良好、来源广泛等优点,被广泛应用于镍锌电池中作为电极材料。本工作采用共沉淀法,调控具有不同镍钴比例的硝酸盐溶液,在室温环境下一步合成镍钴双金属氢氧化物,并将其制备成镍锌电池正极材料。采用X射线衍射仪(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)等对所合成的样品进行表征,观察其微观形貌结构,采用电化学工作站等研究其作为镍锌电池电极材料的电化学性能。研究发现,采用高浓度Na OH溶液作为电解液,比其他通过共沉淀法所制备的镍钴氢氧化物在镍锌电池中所表现出的容量更高。结果表明,当镍钴投料比为4∶1时,样品具有最为出色的容量表现,其中,Ni_(4)Co_(1)-LDH样品在电流密度为0.5 A/g时容量可以达到327.9 m Ah/g。将其作为正极材料、锌箔作为负极,与高浓度的Na OH溶液一起组装成镍锌电池进行电化学测试,在0.5 A/g电流密度下具有230.7 m Ah/g的容量,该研究兼具材料合成快速和性能表现良好等优点,研究结果有望为镍锌电池性能优化提供新思路。
