Fig. 1
From: Black phosphorus ink formulation for inkjet printing of optoelectronics and photonics
BP exfoliation and characterisation. a Photographs of the BP dispersions in NMP, CHP and IPA, centrifuged at 1–4 krpm. b Optical extinction (log–log scale) of the BP dispersions (centrifuged at 4 krpm), the dispersions are diluted to 10 vol% to avoid detector saturation. c Optical scattering with associated fitting (log–log scale) of the dispersions. The scattering is normalised to the 465 nm extinction peak. d Raman spectrum for exfoliated and bulk BP, with intensity normalised to that of the \({A_{\rm{g}}^2}\) peak, I \(\left( {A_{\rm{g}}^2} \right)\). e Raman map of the intensity ratio, I \(\left( {A_{\rm{g}}^1} \right)\)/I \(\left( {A_{\rm{g}}^2} \right)\), with 1 μm spatial step. The grey squares correspond to regions where the Raman intensity is too low for accurate interpretation. f Corresponding histogram of the map in e
