Writing Self-Erasing Images using Metastable Nanoparticle “Inks”


  • This work was supported by the Alfred P. Sloan Fellowship and the Dreyfus Teacher–Scholar Award (both to B.A.G.). R.K. was supported by the NSF Northwestern MRSEC. K.J.M.B. was supported by the NSF Graduate Fellowship.


original image

Mission Impossible: Metal nanoparticles (NPs) coated with photoresponsive ligands are used as “inks” for self-erasing “paper” whereby light-induced self-assembly of the NPs is transduced into local color changes (see picture). Depending on the degree of self-assembly, multicolor images can be written using only one type of NP ink. Duration of image erasure is regulated by the surface concentration of photoactive groups and can range from seconds to days.