Understanding nanoscale molecular order within organic electronic materials is a crucial factor in building better organic electronic devices. At present, techniques capable of imaging molecular order within a polymer are limited in resolution, accuracy, and accessibility. In this work, presented are secondary electron (SE) spectroscopy and secondary electron hyperspectral imaging, which make an exciting alternative approach to probing molecular ordering in poly(3‐hexylthiophene) (P3HT) with scanning electron microscope‐enabled resolution. It is demonstrated that the crystalline content of a P3HT film is reflected by its SE energy spectrum, both empirically and through correlation with nano‐Fourier‐transform infrared spectroscopy, an innovative technique for exploring nanoscale chemistry. The origin of SE spectral features is investigated using both experimental and modeling approaches, and it is found that the different electronic properties of amorphous and crystalline P3HT result in SE emission with different energy distributions. This effect is exploited by acquiring hyperspectral SE images of different P3HT films to explore localized molecular orientation. Machine learning techniques are used to accurately identify and map the crystalline content of the film, demonstrating the power of an exciting characterization technique.

Nano-FTIR and PeakForce quantitative nanomechanical mapping (PF QNM) are new AFM-based techniques that can be applied to plant tissues to get high-resolution spatial distribution of features that are unavailable from bulk characterization. This can be useful for finding changes to plant cell walls by processing technologies, mutations, or the environment. Three poplar hardwoods of varying recalcitrance and composition (high lignin, low lignin, and mutant) were investigated by nano-FTIR and PF QNM. Bulk characterization was carried out by conventional FTIR and NMR of isolated cellulose, hemicelluloses, and lignin. We found that in nano-FTIR spectra of secondary cell walls (SCW) and compound middle lamella (CML), 1162 and 1269 cm −1 could distinctly identify polysaccharides and lignin, respectively. Spatial variability in the content of polysaccharides and lignin was significantly larger in CML than SCW for all three poplars. Cellulose has a disordered structure in CML in comparison to SCW. PF QNM showed that SCW had a higher modulus of elasticity than CML due to the presence of crystalline cellulose in SCW. Differences in the physicochemical properties between the SCW and CML of plants can be probed at nanoscale by these techniques.

Oriented attachment and activated distortion-induced dipoles determine the anisotropic self-assembly and polarized blue fluorescence of organic nanoribbons.