Room-temperature synthesis of (Ag,Cu)2S hollow spheres by cation exchange and their optical properties

Hollow (Ag,Cu)2S microspheres were prepared with spherical aggregates of CuS nanoparticles as templates at room temperature. The products were characterized using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The result showed that when the molar ratio of CuS to Ag+ was 2:1, the obtained product was hollow microspheres with diameter of 700 nm to 1 μm. The shell of the hollow spheres was composed of (Ag,Cu)2S nanoparticles. The absorption of hollow (Ag,Cu)2S spheres was strong in ultraviolet and infrared region but weak in visible region. It will be valuable optical materials for selective absorption or transmission.