Raman microprobe analysis of elastic strain and fracture in electrophoretically deposited CdSe nanocrystal films

The mechanical stability of nanocrystal films is critical for applications, yet largely unexplored. Raman microprobe analysis used here to probe the nanocrystal cores of thick, fractured electrophoretically deposited films of 3.2 nm diameter CdSe nanocrystals measures similar to 2.5% in-plane tensile strain in cores of unfractured films. The crack dimensions determine the overall in-plane film strain, similar to 11.7%, and the film biaxial modulus, similar to 13.8 GPa, from which the biaxial modulus of the trioctylphosphine oxide ligand matrix is inferred, similar to 5.1 GPa.