The growing global demands of safe, low-cost and high working voltage energy storage devices trigger strong interests in novel battery concepts beyond state-of-art lithium-ion battery. Herein, a dualion battery based ...The growing global demands of safe, low-cost and high working voltage energy storage devices trigger strong interests in novel battery concepts beyond state-of-art lithium-ion battery. Herein, a dualion battery based on nanostructured Ni_3S_2/Ni foam@RGO(NSNR) composite anode is developed, utilizing graphite as cathode material and LiPF6-VC-based solvent as electrolyte. The battery operates at high working voltage of 4.2–4.5 V, with superior discharge capacity of ～90 m A h g^(-1) at 100 mA g^(-1), outstanding rate performance, and long-term cycling stability over 500 cycles with discharge capacity retention of ～85.6%. Moreover, the composite simultaneously acts as the anode material and the current collector, and the corrosion phenomenon can be greatly reduced compared to metallic Al anode. Thus, this work represents a significant step forward for practical safe, low-cost and high working voltage dual-ion batteries,showing attractive potential for future energy storage application.展开更多
NiS2 has become a research hotspot of anode materials for Na-ion batteries due to its high theoretical specific capacity.However,the volume effect,the dissolution of polysulfide intermediates and the low conductivity ...NiS2 has become a research hotspot of anode materials for Na-ion batteries due to its high theoretical specific capacity.However,the volume effect,the dissolution of polysulfide intermediates and the low conductivity during the charge/discharge process lead to the low specific capacity and poor cycling stability.NiS2/rGO nanocomposite was prepared by a facile two-step process:GO was prepared by modified Hummers method,and then NiS2/rGO nanocomposite was synthesized by L-cys assisted hydrothermal method.NiS2/rGO nanocomposite shows excellent cycle performance and rate performance,which could be attributed to the mesoporous structure on the graphene skeleton with high conductivity.Besides,the chemical constraint of a unique S—O bond on NiS2 could inhibit the dissolution of intermediates and the loss of irreversible capacity.展开更多
Two-dimensional(2 D)heterostructural Ni2 P/rGO is successfully fabricated by in-situ phosphating selfassembled NiO/rGO composites and shows the enhanced electrochemical performances.In this design,the rGO sheets effec...Two-dimensional(2 D)heterostructural Ni2 P/rGO is successfully fabricated by in-situ phosphating selfassembled NiO/rGO composites and shows the enhanced electrochemical performances.In this design,the rGO sheets effectively reduce the lattice strain created during the phase transformation from NiO to Ni2 P,thereby maintaining ultrathin nanostructures of Ni2 P.The resulting Ni2 P/rGO layered heterostructure gives the composite plenty of pores or channels,good electrical conductivity and well-exposed active sites.Density functional theory(DFT)calculation further demonstrates that the Fermi energy level and electron localize of near Ni atoms in Ni2 P is higher than that of NiO,which endow Ni2 P with faster and more reversible redox reactivity in dynamic.Benefiting from their structural and compositional merits,the as-synthesized Ni2 P/rGO exhibits high specific discharge capacity and excellent rate performance.Furthermore,a hybrid supercapacitor built with Ni2 P/rGO and activated carbon shows a high specific energy of 38.6 Wh/kg at specific power of 375 W/kg.展开更多
Specific topographic Ni anchoring on reduced graphene oxide(rGO) composites show an astronomical potential as effective wave absorbers due to the synergistic electromagnetic loss effects.Herein,Ni/rGO composites with ...Specific topographic Ni anchoring on reduced graphene oxide(rGO) composites show an astronomical potential as effective wave absorbers due to the synergistic electromagnetic loss effects.Herein,Ni/rGO composites with different topography were successfully prepared via hydrothermal in-situ reduction method.The structure and morphology characteristics revealed that particle-like,chain-like,coin-like and flower-like Ni were closely anchored onto rGO,respectively.The electromagnetic wave absorption(EMA) performance revealed that chain-like Ni/rGO exhibited the optimal reflection loss of-43.7 dB with a thickness of 1.8 mm as well as the EAB of 6.1 GHz at 2.0 mm among all samples due to the good impedance match and the synergistic dielectric and magnetic losses.Besides,one conclusion can be drawn that excellent magnetic coupling effect and impedance matching were the main reasons for significantly improving the EMA performance.Considering the systematic dependence of morphology on EMA,this work provides a perspective for designing high-performance absorbing materials.展开更多
基金supported by the National Natural Science Foundation of China (No. 51725401)the Fundamental Research Funds for the Central Universities (FRF-TP-15-002C1 and FRF-TP17-002C2)
文摘The growing global demands of safe, low-cost and high working voltage energy storage devices trigger strong interests in novel battery concepts beyond state-of-art lithium-ion battery. Herein, a dualion battery based on nanostructured Ni_3S_2/Ni foam@RGO(NSNR) composite anode is developed, utilizing graphite as cathode material and LiPF6-VC-based solvent as electrolyte. The battery operates at high working voltage of 4.2–4.5 V, with superior discharge capacity of ～90 m A h g^(-1) at 100 mA g^(-1), outstanding rate performance, and long-term cycling stability over 500 cycles with discharge capacity retention of ～85.6%. Moreover, the composite simultaneously acts as the anode material and the current collector, and the corrosion phenomenon can be greatly reduced compared to metallic Al anode. Thus, this work represents a significant step forward for practical safe, low-cost and high working voltage dual-ion batteries,showing attractive potential for future energy storage application.
基金support from the National Natural Science Foundation of China(NSFC,No.51171033)The Fundamental Research Funds for the Central Universities(No.DUT19LAB29)。
文摘NiS2 has become a research hotspot of anode materials for Na-ion batteries due to its high theoretical specific capacity.However,the volume effect,the dissolution of polysulfide intermediates and the low conductivity during the charge/discharge process lead to the low specific capacity and poor cycling stability.NiS2/rGO nanocomposite was prepared by a facile two-step process:GO was prepared by modified Hummers method,and then NiS2/rGO nanocomposite was synthesized by L-cys assisted hydrothermal method.NiS2/rGO nanocomposite shows excellent cycle performance and rate performance,which could be attributed to the mesoporous structure on the graphene skeleton with high conductivity.Besides,the chemical constraint of a unique S—O bond on NiS2 could inhibit the dissolution of intermediates and the loss of irreversible capacity.
基金supported by the DNL Cooperation Fund,CAS(No.DNL201915)National Science Foundation for Excellent Young Scholars of China(No.21922815)+1 种基金National Natural Science Foundation of China(No.21975275)Key Research and Development(R&D)Projects of Shanxi Province(No.201903D121007)。
文摘Two-dimensional(2 D)heterostructural Ni2 P/rGO is successfully fabricated by in-situ phosphating selfassembled NiO/rGO composites and shows the enhanced electrochemical performances.In this design,the rGO sheets effectively reduce the lattice strain created during the phase transformation from NiO to Ni2 P,thereby maintaining ultrathin nanostructures of Ni2 P.The resulting Ni2 P/rGO layered heterostructure gives the composite plenty of pores or channels,good electrical conductivity and well-exposed active sites.Density functional theory(DFT)calculation further demonstrates that the Fermi energy level and electron localize of near Ni atoms in Ni2 P is higher than that of NiO,which endow Ni2 P with faster and more reversible redox reactivity in dynamic.Benefiting from their structural and compositional merits,the as-synthesized Ni2 P/rGO exhibits high specific discharge capacity and excellent rate performance.Furthermore,a hybrid supercapacitor built with Ni2 P/rGO and activated carbon shows a high specific energy of 38.6 Wh/kg at specific power of 375 W/kg.
基金the financial support for this work by the National Natural Science Foundation of China (Nos.51903223 and U1704162)China Postdoctoral Science Foundation (No.2018M642781)。
文摘Specific topographic Ni anchoring on reduced graphene oxide(rGO) composites show an astronomical potential as effective wave absorbers due to the synergistic electromagnetic loss effects.Herein,Ni/rGO composites with different topography were successfully prepared via hydrothermal in-situ reduction method.The structure and morphology characteristics revealed that particle-like,chain-like,coin-like and flower-like Ni were closely anchored onto rGO,respectively.The electromagnetic wave absorption(EMA) performance revealed that chain-like Ni/rGO exhibited the optimal reflection loss of-43.7 dB with a thickness of 1.8 mm as well as the EAB of 6.1 GHz at 2.0 mm among all samples due to the good impedance match and the synergistic dielectric and magnetic losses.Besides,one conclusion can be drawn that excellent magnetic coupling effect and impedance matching were the main reasons for significantly improving the EMA performance.Considering the systematic dependence of morphology on EMA,this work provides a perspective for designing high-performance absorbing materials.
