| 초록 |
Near infrared (NIR) electrochromic materials are attracting much interest in academic and industry including solar heat regulation system, optical telecommunication, military camouflage, and photodynamic therapy. Copper sulfide nanocrystals (Cu2-xS NCs) exhibit absorbance in NIR based on localized surface plasmon resonance (LSPR) of plentiful holes in the material. The density of holes is determined from stoichiometric mismatch (x) between copper and sulfur atoms, and, therefore, absorbance of materials can be controlled by varying x. Here we introduce electrochemical methods of controlling x using lithium and sodium ions and the resulting NIR absorbance from LSPR. Specifically, by using a film of Cu1.1S NCs on ITO was used as a working electrode, Pt wire as a counter electrode, and Ag wire as a reference electrode and electrolyte containing lithium perchlorate or , sodium perchlorate, we confirmed metal ion insertion leads change in NIR absorbance reversibly. |
