Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique properties.However,its ultrafast photonics applications are still rare.Here,the few-layer Ti_(3)CN MXene was successfully prepared b...Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique properties.However,its ultrafast photonics applications are still rare.Here,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination technique.The nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan technique.The asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of4.05×10^(-2)cm/GW,which was one order of magnitude larger than that of black phosphorus(BP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully realized.Furthermore,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 MHz.The optical modulation device based on few-layer Ti_(3)CN MXene shows good performance.Our work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.展开更多
Renewable energy powered electrocatalytic water splitting is a promising strategy for hydrogen generation,and the design and development of high-efficiency and earth-abundant electrocatalysts for hydrogen evolution re...Renewable energy powered electrocatalytic water splitting is a promising strategy for hydrogen generation,and the design and development of high-efficiency and earth-abundant electrocatalysts for hydrogen evolution reaction(HER)are highly desirable.Herein,MoS2 nanoflowers decorated two-dimensional carbonitride-based MXene Ti3CN(OH)x hybrids have been constructed by etching and post-hydrothermal methods.The electrochemical performance of the as-obtained Ti_(3)CN(OH)_(x)@MoS_(2)hybrids having a quasi core-shell structure is fascinating:An overpotential of 120 mV and a Tafel slope of 64 mV∙dec^(−1)can be delivered at a current density of 10 mA∙cm^(−2).And after 3,000 cyclic voltammetry cycles,it can be seen that there is no apparent attenuation.Both the experimental results and density functional theory(DFT)calculations indicate that the synergetic effects between Ti_(3)CN(OH)x and MoS_(2)are responsible for the robust electrochemical HER performance.The electrons of-OH group in Ti_(3)CN(OH)x are transferred to MoS_(2),making the adsorption energy of the composite for H almost vanish.The metallic Ti_(3)CN(OH)x is also beneficial to the fast charge transfer kinetics.The construction of MXene-based hybrids with optimal electronic structure and unique morphology tailored to the applications can be further used in other promising energy storage and conversion devices.展开更多
基金financial supports from the National Natural Science Foundation of China(Nos.52004157,U1860203,52022054,51974181)the Shanghai Sailing Program,China(No.21YF1412900)+5 种基金the Shanghai Rising-Star Program,China(No.19QA1403600)the Shanghai Engineering Research Center of Green Remanufacture of Metal Parts,China(No.19DZ2252900)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,China(No.TP2019041)the“Shuguang Program”supported by the Shanghai Education Development Foundation and the Shanghai Municipal Education Commission,China(No.21SG42)the Independent Research and Development Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University,China(No.SKLASS 2020-Z10)the Science and Technology Commission of Shanghai Municipality,China(No.19DZ2270200).
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.12004208 and 62005177)the Natural Science Foundation of Shandong Province of China(Grant No.ZR2021QF128)+2 种基金the Qilu University of Technology(Shandong Academy of Sciences)Education and Industry Integration and Innovation Pilot(Grant Nos.2022PY022 and 2022JBZ01-04)The author also thanks to support and funding of King Khalid University through Research Center for Advanced Materials Science(RCAMS)(Grant No:RCAMS/KKU/008/21).
文摘Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique properties.However,its ultrafast photonics applications are still rare.Here,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination technique.The nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan technique.The asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of4.05×10^(-2)cm/GW,which was one order of magnitude larger than that of black phosphorus(BP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully realized.Furthermore,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 MHz.The optical modulation device based on few-layer Ti_(3)CN MXene shows good performance.Our work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.
基金supported by the National Natural Science Foundation of China(Nos.62004143 and 21902108)the Key Research and Development(R&D)Program of Hubei Province(No.2022BAA084)+1 种基金the Central Government Guided Local Science and Technology Development Special Fund Project(No.2020ZYYD033),the Natural Science Foundation of Hubei Province(No.2021CFB133)the Knowledge Innovation Program of Wuhan-Shuguang Project(No.2022010801020355).
文摘Renewable energy powered electrocatalytic water splitting is a promising strategy for hydrogen generation,and the design and development of high-efficiency and earth-abundant electrocatalysts for hydrogen evolution reaction(HER)are highly desirable.Herein,MoS2 nanoflowers decorated two-dimensional carbonitride-based MXene Ti3CN(OH)x hybrids have been constructed by etching and post-hydrothermal methods.The electrochemical performance of the as-obtained Ti_(3)CN(OH)_(x)@MoS_(2)hybrids having a quasi core-shell structure is fascinating:An overpotential of 120 mV and a Tafel slope of 64 mV∙dec^(−1)can be delivered at a current density of 10 mA∙cm^(−2).And after 3,000 cyclic voltammetry cycles,it can be seen that there is no apparent attenuation.Both the experimental results and density functional theory(DFT)calculations indicate that the synergetic effects between Ti_(3)CN(OH)x and MoS_(2)are responsible for the robust electrochemical HER performance.The electrons of-OH group in Ti_(3)CN(OH)x are transferred to MoS_(2),making the adsorption energy of the composite for H almost vanish.The metallic Ti_(3)CN(OH)x is also beneficial to the fast charge transfer kinetics.The construction of MXene-based hybrids with optimal electronic structure and unique morphology tailored to the applications can be further used in other promising energy storage and conversion devices.