Although MXenes is highly attractive as anode materials of lithium ion batteries,it sets a bottleneck for higher capacity of the V2CTxMXene due to the limited interlayer space and the derived surface terminations.Here...Although MXenes is highly attractive as anode materials of lithium ion batteries,it sets a bottleneck for higher capacity of the V2CTxMXene due to the limited interlayer space and the derived surface terminations.Herein,the cation intercalation and ion-exchange were well employed to achieve a K+and Ca2+intercalated V2CTxMXene.A larger interlayer distance and low F surface terminations were thereof obtained,which accelerates the ion transport and promotes the delicate surface of V2CTx MXene.As a result,a package of enhanced capacity,rate performance and cyclability can be achieved.Furthermore,the ion exchange approach can be extended to other 2 D layered materials,and both the interlayer control and the surface modification will be achieved.展开更多
Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical ...Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.展开更多
MXene is a rising star of two-dimensional(2D)materials for energy relative applications,however,the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk o...MXene is a rising star of two-dimensional(2D)materials for energy relative applications,however,the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk of splashing or pouring liquid solutions.In this work,we developed a water-free ionothermal synthesis of 2D Ti3C2 MXene via etching pristine Ti3AlC2 MAX in low-cost choline chloride and oxalic acid based deep eutectic solvents(DES)with the presence of NH4F,thus it was highly safe and convenient to operate solid precursor and product materials at room temperature.Benefited from the low vapor pressure and solvating properties of DES,the prepared Ti3C2(denoted as DES-Ti3C2)possessed a high purity up to 98% compared with 95% for HF etched Ti3C2(denoted as HF-Ti3C2).Notably,an expanded interlayer spacing of 1.35 nm could be achieved due to the intercalation of choline cations in DES-Ti3C2,larger than that of HF-Ti3C2(0.98 nm).As a result,the DES-Ti3C2 anodes exhibited enhanced lithium storage performance,such as high reversible capacity of 208 m Ah g-1at 0.5 A g-1,and long cycle life over 400 times,outperforming most reported pure MXene anodes.The ionothermal synthesis of MXene developed here may pave a new way to safely prepare other MXene for various energy relating applications.展开更多
基金financial support provided by the National Natural Science Foundation of China(No.51932005)Liao Ning Revitalization Talents Program(XLYC1807175)+4 种基金the Joint Research Fund Liaoning Shenyang National Laboratory for Materials Science(SYNL)(20180510047)the Research Fund of SYNL(L2019F38)the Youth Innovation Promotion Association CAS(2015152)the Program for the Development of Science and Technology of Jilin Province(No.20190201309JC)the Project of Development and Reform Commission of Jilin Province(No.2019C042-1)。
文摘Although MXenes is highly attractive as anode materials of lithium ion batteries,it sets a bottleneck for higher capacity of the V2CTxMXene due to the limited interlayer space and the derived surface terminations.Herein,the cation intercalation and ion-exchange were well employed to achieve a K+and Ca2+intercalated V2CTxMXene.A larger interlayer distance and low F surface terminations were thereof obtained,which accelerates the ion transport and promotes the delicate surface of V2CTx MXene.As a result,a package of enhanced capacity,rate performance and cyclability can be achieved.Furthermore,the ion exchange approach can be extended to other 2 D layered materials,and both the interlayer control and the surface modification will be achieved.
基金sponsored by the National Key Research and Development Program of China(2016YFA0201700,2016YFA0201702)the Fundamental Research Funds for the Central Universities(2232019A3-06,2232019D3-02)+2 种基金the National Key Research and Development Program of China(2018YFC1105800)the National Natural Science Foundation of China(21674018,51903045)the Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-Dimension Materials(18520750400).
文摘Fluorescent silk is fundamentally important for the development of future tissue engineering scaffolds.Despite great progress in the preparation of a variety of colored silks,fluorescent silk with enhanced mechanical properties has yet to be explored.In this study,we report on the fabrication of intrinsically super-strong fluorescent silk by feeding Bombyx mori silkworm carbon nanodots(CNDs).The CNDs were incorporated into silk fibroin,hindering the conformation transformation,confining crystallization,and inducing orientation of mesophase.The resultant silk exhibited super-strong mechanical properties with breaking strength of 521.9±82.7 MPa and breaking elongation of 19.2±4.3%,improvements of 55.1%and 53.6%,respectively,in comparison with regular silk.The CNDs-reinforced silk displayed intrinsic blue fluorescence when exposed to 405 nm laser and exhibited no cytotoxic effect on cells,suggesting that multi-functional silks would be potentially useful in bioimaging and other applications.
基金financially supported by the National Natural Science Foundation of China (Nos.21601029, 21601030)the Open Project Program of the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry (Nos.2017-33, 2017-26)the Fundamental Research Funds for the Central Universities of China (No.N180503012)。
文摘MXene is a rising star of two-dimensional(2D)materials for energy relative applications,however,the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk of splashing or pouring liquid solutions.In this work,we developed a water-free ionothermal synthesis of 2D Ti3C2 MXene via etching pristine Ti3AlC2 MAX in low-cost choline chloride and oxalic acid based deep eutectic solvents(DES)with the presence of NH4F,thus it was highly safe and convenient to operate solid precursor and product materials at room temperature.Benefited from the low vapor pressure and solvating properties of DES,the prepared Ti3C2(denoted as DES-Ti3C2)possessed a high purity up to 98% compared with 95% for HF etched Ti3C2(denoted as HF-Ti3C2).Notably,an expanded interlayer spacing of 1.35 nm could be achieved due to the intercalation of choline cations in DES-Ti3C2,larger than that of HF-Ti3C2(0.98 nm).As a result,the DES-Ti3C2 anodes exhibited enhanced lithium storage performance,such as high reversible capacity of 208 m Ah g-1at 0.5 A g-1,and long cycle life over 400 times,outperforming most reported pure MXene anodes.The ionothermal synthesis of MXene developed here may pave a new way to safely prepare other MXene for various energy relating applications.
