Ag(2)S Quantum Dots Based on Flower-like SnS(2) as Matrix and Enhanced Photocatalytic Degradation

Ag(2)S quantum dots were dispersed on the surface of SnS(2) nanoflowers forming a heterojunction via in-situ ion exchange to improve photocatalytic degradation of RhB. All samples exhibit the hexagonal wurtzite structure. The size of Ag(2)S@SnS(2) composites are ~ 1.5 μm flower-like with good crystallinity. Meanwhile, the E(g) of 3% Ag(2)S@SnS(2) is close to that of pure SnS(2). Consequently, the 3% Ag(2)S@SnS(2) composite displays the excellent photocatalytic performance under simulated sunlight irradiation with good cycling stability, compared to the pure SnS(2) and other composites. Due to the blue and yellow luminescence quenching, the photogenerated electrons and holes is effectively separated in the 3% Ag(2)S@SnS(2) sample. Especially, the hydroxyl radicals and photogenerated holes are main active species.