Plasmonic behavior of copper iron sulfide nanoparticles

Copper vacancies in copper chalcogenides result in sufficiently high levels of charge carriers to generate plasmon resonances. Growth of the number of copper vacancies with air exposure is exacerbated in nanoparticles.1 We present here investigations into the stabilization of plasmonic copper sulfide-based semiconductors. Incorporation of iron slows increase in the copper vacancy concentration.2 Here we will discuss the affect of iron incorporation into copper sulfide nanoparticles on the plasmonic behavior. Various phases were produced, ranging from different polymorphs of Cu2S to CuFeS2, including solid solutions. The solid-state structure, band gaps and edges, and plasmon band absorption of these copper iron sulfide nanoparticles were responsive to the extent of iron incorporation, as investigated by powder X-ray diffraction, cyclic voltammetry, and visible/near-IR light absorption spectroscopy. The surface chemistry influences the plasmonic behavior of these copper iron sulfide nanoparticles and will be examined.3

(1) Lotfipour, M.; Machani, T.; Rossi, D. P.; Plass, K. E. Chem. Mater. 2011, 23, 3032–3038.
(2) Machani, T.; Rossi, D. P.; Golden, B. J.; Jones, E. C.; Lotfipour, M.; Plass, K. E. Chem. Mater. 2011, 23, 5491–5495.
(3) Freymeyer, N. J.; Cunningham, P. D.; Jones, E. C.; Golden, B. J.; Wiltrout, A. M.; Plass, K. E. Cryst. Growth Des. 2013, 13, 4059–4065.