We report on a facile interfacial self-assembly approach to fabricate large-scale metal nanoparticle superlattice sheets from nonspherical core-shell nanoparticles, which exhibited reversible plasmonic responses to repeated mechanical stretching. Monodisperse Au@Ag nanocubes (NCs) and Au@Ag nanocuboids (NBs) could be induced to self-assembly at the hexane/water interface, forming uniform superlattices up to at least 13 cm2 and giving rise to mirror-like reflection. Such large-area mirror-like superlattice sheets exhibited reversible plasmonic responses to external mechanical strains. Under stretching, the dominant plasmonic resonance peak for both NB and NC superlattice sheets shifted to blue, following a power-law function of the applied strain. Interestingly, the power-law exponent (or the decay rate) showed a strong shape dependence, where a faster rate was observed for NB superlattice sheets than that for NC superlattice sheets.
Guo, P., Sikdar, D., Huang, X., Si, K. J., Su, B., Chen, Y., Xiong, W., Yap, L. W., Premaratne, M., & Cheng, W. (2014). Large-scale self-assembly and stretch-induced plasmonic properties of core-shell metal nanoparticle superlattice sheets. Journal of Physical Chemistry C, 118(46), 26816 - 26824. https://doi.org/10.1021/jp508108a