Fig. 1: Characterizations of z-PNBs.
From: Unzipping of black phosphorus to form zigzag-phosphorene nanobelts
a TEM image of a single z-PNB with the zigzag directions, corresponding to the [100] direction. b Corresponding HRTEM image of a. c Corresponding SAED pattern of b, the zigzag and armchair directions are shown by white arrows. Inset: intensity of (200) and (101) fast Fourier transform (FFT) patterns. d TEM image of an individual twisted z-PNBs. e Size distribution diagram of the TEM images statistics on 73 z-PNBs. Left, diagrams of length as a function of width for 73 z-PNBs; right, frequency distribution of z-PNBs. length (top), width (middle), and aspect ratio (bottom). f Thickness distribution diagram from the AFM images of 56 z-PNBs. Inset: AFM image of two typical belts onto a 300 nm SiO2/Si substrate with the thickness of ~2.4 nm (left) and ~0.8 nm (right), corresponding to four-layer and monolayer phosphorene, respectively. g XRD patterns of as-prepared z-PNBs. Inset: ten times amplification of XRD patterns in dashed rectangle areas of z-PNBs. h High-resolution XPS spectra of the P 2p signal for electrochemically exfoliated z-PNBs with ∑X2 of 17.86. Inset: 15 times amplification of XPS signals in dashed rectangles. i Raman spectra (λ = 532 nm) of z-PNBs and bulk black phosphorus on SiO2/Si substrates with 300 nm in thickness, respectively. j Normalized \(A_g^2\) Raman band of z-PNBs from polarization-resolved Raman spectra of a z-PNB (Supplementary Fig. 5c) as a function of rotation angle. Red dots and lines are the experimental data of z-PNBs and the fitting curve by a sin2θ function. Top right: optical image of a z-PNB on SiO2/Si substrates with 300 nm in thickness. The arrows indicate the identified armchair and zigzag directions, respectively.
