摘要
The production of two-dimensional nanosheets(2D NSs)with all sizes(1-100 nm)and few(<10)layers is highly desired but far from satisfactory.Herein,we report an all-physical top-down method to produce indium chalcogenide(In2X3(X=S,Se,Te))NSs with wide-range(150-3.0 nm)controlled sizes.The method combines silica-assisted ball-milling and sonication-assisted solvent exfoliation to fabricate multiscale NSs with varying distributions,which are then precisely separated by cascade centrifugation.Multiple characterization techniques reveal that the as-produced In2X3 NSs are intrinsic and defect-free and remainβ-phase during the whole process.The redispersions of In2X3 NSs exhibit prominent excitation wavelength-,solvent-,concentration-,and size-dependent photoluminescence.The NSs-poly(methyl methacrylate)(PMMA)hybrid thin films demonstrate strong size effects in nonlinear saturation absorption.The absolute modulation depths of 35.4%,43.3%,47.2%and saturation intensities of 1.63,1.05,0.83 MW·cm^(−2)(i.e.,163,105,and 83 nJ·cm^(−2))are derived for the In_(2)S_(3),In_(2)Se_(3),and In2Te3 quantum sheets,respectively.Our method paves the way for mass production and full exploration of full-scale 2D NSs.
基金
supported by the National Natural Science Foundation of China(Nos.52073070,21673054,11874130,and 22073022)
Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000)
National Key R&D Program of China(No.2018YFA0703700)
DNL Cooperation Fund,CAS(DNL202016).
