Fig. 3
From: Chemically modified graphene films with tunable negative Poisson’s ratios
Microstructural origins of the negative Poisson’s ratio (NPR) effect. a X-ray diffraction patterns of the e-GO35, f-GO35, e-GO0, and f-GO0 films. b Poisson’s ratios and the full-width at half-maximum (FWHM) measured for the e-GO0 films under different amplitudes of pre-stretch. c Relationship between the value of IG(//)/IG(⊥) and the angle of sheet (α) in the films (inset: the polarized Raman setup). d The G band intensity, IG(β), plotted as a function of β. Black dots and lines are the experimental data of e-GO0 films without pre-stretch and the fitting curve using Eq. (2), while the red (blue) ones are the data and fitting curve for e-GO0 films under 30 (60) mN pre-stretch. The error bars in panel (b) indicate the standard errors (three samples for the Poisson’s ratios and four samples for FWHM). Source data are provided as a Source Data file
