Transition metal oxides(TMOs)have been thought of potential anodic materials for lithium-ion batteries(LIBs)owing to their intriguing properties.However,the limited conductivity and drastic volume change still hinder ...Transition metal oxides(TMOs)have been thought of potential anodic materials for lithium-ion batteries(LIBs)owing to their intriguing properties.However,the limited conductivity and drastic volume change still hinder their practical applications.Herein,a metal oxyacid salts-confined pyrolysis strategy is proposed to construct hierarchical porous metal oxide@carbon(MO@C,MO=MoO_(2),V_(2)O_(5),WO_(3))composites for solving the aforementioned problems.A water-evaporation-induced self-assembly mechanism has been put forward for fabricating the MO@polyvinyl pyrrolidone(PVP)@SiO_(2)precursors.After the following pyrolysis and etching process,small MO nanoparticles can be successfully encapsulated in the hierarchical porous carbon framework.Profiting from the synergistic effect of MO nanoparticles and highly conductive carbon framework,MO@C composites show excellent electrochemical properties.For example,the as-obtained MoO_(2)@C composite exhibits a large discharge capacity(1513.7 mAh·g^(−1)at 0.1 A·g^(−1)),good rate ability(443.5 mAh·g^(−1)at 5.0 A·g^(−1)),supernal long-lived stability(669.1 mAh·g^(−1)after 1000 cycles at 1.0 A·g^(−1)).This work will inspire the design of novel anode materials for high-performance LIBs.展开更多
We experimentally demonstrate self-trapping of light, as a result of plasmonic resonant optical nonlinearity,in both aqueous and organic(toluene) suspensions of gold nanorods. The threshold power for soliton formation...We experimentally demonstrate self-trapping of light, as a result of plasmonic resonant optical nonlinearity,in both aqueous and organic(toluene) suspensions of gold nanorods. The threshold power for soliton formation is greatly reduced in toluene as opposed to aqueous suspensions. It is well known that the optical gradient forces are optimized at off-resonance wavelengths at which suspended particles typically exhibit a strong positive(or negative) polarizability. However, surprisingly, as we tune the wavelength of the optical beam from a continuous-wave(CW) laser, we find that the threshold power is reduced by more than threefold at the plasmonic resonance frequency. By analyzing the optical forces and torque acting on the nanorods, we show theoretically that it is possible to align the nanorods inside a soliton waveguide channel into orthogonal orientations by using merely two different laser wavelengths. We perform a series of experiments to examine the transmission of the soliton-forming beam itself, as well as the polarization transmission spectrum of a low-power probe beam guided along the soliton channel. It is found that the expected synthetic anisotropic properties are too subtle to be clearly observed, in large part due to Brownian motion of the solvent molecules and a limited ordering region where the optical field from the self-trapped beam is strong enough to overcome thermodynamic fluctuations. The ability to achieve tunable nonlinearity and nanorod orientations in colloidal nanosuspensions with low-power CW laser beams may lead to interesting applications in all-optical switching and transparent display technologies.展开更多
Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si structure has been fabricated with a preferentially （111）-orientated Bi 2 Ti 2 O 7 seeding layer as a ferroelectric gate of metal-ferroelectric-insulator field effect ...Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si structure has been fabricated with a preferentially （111）-orientated Bi 2 Ti 2 O 7 seeding layer as a ferroelectric gate of metal-ferroelectric-insulator field effect transistor.Bi 3.54 Nd 0.46 Ti 3 O 12 and Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 films are both well-crystallized when annealed at 680℃ for 40 min,and have smooth,dense and crack-free surfaces.The width of memory window of the ferroelectric gate increases with increasing electric field applied to the Bi 3.54 Nd 0.46 Ti 3 O 12 thin films.The width of memory window of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si with seeding layer is relatively wider than that of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Si at the same bias voltage,and the counterclockwise hysteresis curve of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si is referred to as polarization type switching at different voltages.Bi 2 Ti 2 O 7 seeding layer plays an important role in alleviating the element interdiffusion between Bi 3.54 Nd 0.46 Ti 3 O 12 and Si.展开更多
基金the Taishan Scholar Project of Shandong Province(No.tsqn201909115)And this work was partly supported by Qingdao University of Science and Technology Hua Xue 201919(No.QUSTHX201919).
文摘Transition metal oxides(TMOs)have been thought of potential anodic materials for lithium-ion batteries(LIBs)owing to their intriguing properties.However,the limited conductivity and drastic volume change still hinder their practical applications.Herein,a metal oxyacid salts-confined pyrolysis strategy is proposed to construct hierarchical porous metal oxide@carbon(MO@C,MO=MoO_(2),V_(2)O_(5),WO_(3))composites for solving the aforementioned problems.A water-evaporation-induced self-assembly mechanism has been put forward for fabricating the MO@polyvinyl pyrrolidone(PVP)@SiO_(2)precursors.After the following pyrolysis and etching process,small MO nanoparticles can be successfully encapsulated in the hierarchical porous carbon framework.Profiting from the synergistic effect of MO nanoparticles and highly conductive carbon framework,MO@C composites show excellent electrochemical properties.For example,the as-obtained MoO_(2)@C composite exhibits a large discharge capacity(1513.7 mAh·g^(−1)at 0.1 A·g^(−1)),good rate ability(443.5 mAh·g^(−1)at 5.0 A·g^(−1)),supernal long-lived stability(669.1 mAh·g^(−1)after 1000 cycles at 1.0 A·g^(−1)).This work will inspire the design of novel anode materials for high-performance LIBs.
基金Army Research Office(ARO)(W911NF-15-1-0413)National Science Foundation(NSF)(PHY-1404510)+1 种基金National Key R&D Program of China(2017YFA0303800)National Natural Science Foundation of China(NSFC)(11504184)
文摘We experimentally demonstrate self-trapping of light, as a result of plasmonic resonant optical nonlinearity,in both aqueous and organic(toluene) suspensions of gold nanorods. The threshold power for soliton formation is greatly reduced in toluene as opposed to aqueous suspensions. It is well known that the optical gradient forces are optimized at off-resonance wavelengths at which suspended particles typically exhibit a strong positive(or negative) polarizability. However, surprisingly, as we tune the wavelength of the optical beam from a continuous-wave(CW) laser, we find that the threshold power is reduced by more than threefold at the plasmonic resonance frequency. By analyzing the optical forces and torque acting on the nanorods, we show theoretically that it is possible to align the nanorods inside a soliton waveguide channel into orthogonal orientations by using merely two different laser wavelengths. We perform a series of experiments to examine the transmission of the soliton-forming beam itself, as well as the polarization transmission spectrum of a low-power probe beam guided along the soliton channel. It is found that the expected synthetic anisotropic properties are too subtle to be clearly observed, in large part due to Brownian motion of the solvent molecules and a limited ordering region where the optical field from the self-trapped beam is strong enough to overcome thermodynamic fluctuations. The ability to achieve tunable nonlinearity and nanorod orientations in colloidal nanosuspensions with low-power CW laser beams may lead to interesting applications in all-optical switching and transparent display technologies.
文摘Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si structure has been fabricated with a preferentially （111）-orientated Bi 2 Ti 2 O 7 seeding layer as a ferroelectric gate of metal-ferroelectric-insulator field effect transistor.Bi 3.54 Nd 0.46 Ti 3 O 12 and Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 films are both well-crystallized when annealed at 680℃ for 40 min,and have smooth,dense and crack-free surfaces.The width of memory window of the ferroelectric gate increases with increasing electric field applied to the Bi 3.54 Nd 0.46 Ti 3 O 12 thin films.The width of memory window of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si with seeding layer is relatively wider than that of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Si at the same bias voltage,and the counterclockwise hysteresis curve of Au/Bi 3.54 Nd 0.46 Ti 3 O 12 /Bi 2 Ti 2 O 7 /Si is referred to as polarization type switching at different voltages.Bi 2 Ti 2 O 7 seeding layer plays an important role in alleviating the element interdiffusion between Bi 3.54 Nd 0.46 Ti 3 O 12 and Si.
