Tunable near-infrared localized surface plasmon resonances of heterostructured Cu_1.94S-ZnS nanocrystals

摘要

Strong near-infrared (NIR) localized surface plasmon resonances (LSPRs) have been observed in spherical Cu1.94S nanocrystals and matchstick-like Cu1.94S-ZnS heterostructured nanocrystals, which have been synthesized using a simple one-pot approach without any injection and pre-synthesis of metal precursors. The LSPRs peak of the Cu1.94S nanocrystals could be tuned from 1680 nm to 1375 nm by heterogrowth of ZnS onto the Cu1.94S nanocrystals due to the increase of free carriers (holes). The LSPRs absorbance can be optimized to 1322 nm by prolonging the growth time of the heterostructured nanocrystals, which may be used as a light absorbing agent for photothermal therapy.