Fast electron transfer and enhanced visible light photocatalytic activity using multi-dimensional components of carbon quantum dots@3D daisy-like In₂S₃/single-wall carbon nanotubes

One of current ideal thought to reduce the recombination of photogenerated electrons and holes from semiconductors is constructing Multi-dimensional semiconductor-carbon (S-C) heterostructures. As well as acting to photo-degrade the organic contaminant and decrease the toxicity, β-In₂S₃ is chosen as a potential semiconductors for photocatalysts. Relative good photocatalytic properties delivered on β-In₂S₃, however, the fast recombination of photogenerated charge carriers are often appeared, causing reduced further application. Carbon quantum dots (CQDs) involve the introduction of plasma effect into the zero-dimensional nanomaterials in order to arouse an effect: either promoting the charge carriers transfer or plasma energy conversion of the photo-excited CQDs. However, state of the two components also encompass the poor quantum yield existed in the CQDs by its serious agglomeration. Thereby, the delivery of extraordinary ballistic electrical and thermal conductivity on single-walled carbon nanotubes (SWNTs), have shown potential for use in a variety of semiconductors decorating application. Herein, we show that a novel CQDs@In₂S₃/SWNTs composite in the Multi-dimensional (3D) hierarchical superstructures with an enhanced photocatalytic efficiency. The ESR analysis and free radicals trapping experiments indicated that the O₂•⁻ and h⁺ were the main active species for the photocatalytic degradation. The potential photocatalytic mechanism of the three components is discussed and the direction in the plasma effect exhibited in CQDs is also considered, with a particular focus on photocatalytic area.