Free-standing hybrid films comprising of ultra-dispersed titania nanocrystals and hierarchical conductive network for excellent high rate performance of lithium storage

The construction of advanced electrode materials is key to the field of energy storage.Herein,a free-standing anatase titania(TiO_(2))nanocrystal/carbon nanotube(CNT)film is reported using a simple and scalable sol-gel method,followed by calcination.This unique free-standing film comprises ultra-small TiO_(2) nanocrystals(~5.9 nm)and super-aligned CNTs,with ultra-dispersed TiO_(2) nanocrystals on the surfaces of the CNTs.On the one hand,these TiO_(2) nanocrystals can significantly decrease the diffusion distance of the charges and on the other hand,the cross-linked CNTs can act as a three-dimensional(3D)conductive network,allowing the fast transport of electrons.In addition,the film is free-standing,without requiring electrode fabrication and additional conductive agents and binders.Owing to these above synergistic effects,the film is directly used as an anode in Li-ion batteries,and delivers a high discharge capacity of~105 mAh·g^(−1) at high rate of 60 C(1 C=170 mA·g^(−1))and excellent cycling performance over 2,500 cycles at 30 C.These results indicate that the free-standing anatase TiO_(2) nanocrystal/CNT film affords a superior performance among the various TiO_(2) materials and can be a promising anode material for fast-charging Li-ion batteries.Moreover,the TiO_(2)/CNT film exhibits an areal capacity of up to 2.4 mAh·cm^(−2),confirming the possibility of its practical use.

Construction of ternary heterojunction Agl/C-MoS_(2) nanosheets with enhanced visible-light photocatalytic property and self-cleaning performance

Carbon-molybdenum disulfide(C-MoS_(2))ultrathin nanosheets were prepared by a hydrothermal process,and then Agl/C-MoS_(2) were synthesized via an/n-situ deposition method.This ternary heterojunction composite exhibited better photo-catalytic activity compared with those of one-component(pristine MoS_(2))and bicomponent(Agl/MoS_(2) and C-MoS_(2))materials for the degradation of organic dyes under the visible-light irradiation.In particular,by comparing with Agl/MoS_(2),the significant role of conductive amorphous carbon in Agl/C-MoS_(2) in enhancing the charge transfer during the photocatalytic degradation of dyes was first confirmed by photocurrent response and electrochemical impedance spectroscopy(EIS).A possible photocatalytic mechanism was proposed based on the capture experiment results.Furthermore,a straightforward and interesting way had been applied to test the recycled/newly-prepared Agl/C-MoS_(2) composite for revealing its distinctive self-cleaning performance and recyclability characteristic besides its good photocatalytic activity.This work could provide a reference for the design of other new ternary heterojunction composite materials with special structures and properties.