Carbon dot (CD) and palladium nanoparticles (Pd NPs) composites are semiconducting materials having tremendous applications in catalysis with suitable bandgap. However, their combination with suitable polymer matrix in sono-photo-catalysis has not been explored. Herein, we have synthesized and characterized a new nano-hybrid catalyst from polyamide cross-linked CD-polymer and subsequent deposition of Pd NPs. Sonocatalytic activity of 99% rhodamine B dye-degradation was achieved in mere 5 minutes (min) under dark. Model catalyst replacing CD with benzene and other control studies revealed that synergistic effects of CD and Pd NPs enhances the sonocatalytic activity of nano-hybrid catalyst. Interestingly, visible light did not influence the activity significantly. While mechanistic investigations suggest that generation of reactive oxygen species on the surface of CD-polymer initiated by ultrasound which further facilitated by Pd NPs is the key for remarkable catalytic activity (rate constant 0.99 min<sup>-1</sup>). Recyclable heterogeneous catalyst under ambient conditions are promising for the utility of exploring sono-assisted dark-catalysis for several avenues.
Efficient and reusable Cu (II)-metalated silica-based inorganic-organic hybrid catalyst for dye degradation