π-π-π stacking for capturing-releasing Au clusters in meso-structured system

Highlights: • A smart pH-responsive system based on mesoporous silica nanoparticles modified by molecular tweezers is developed. • The π-π-π stacking has been used to capture and stabilize the Au clusters in the pores of MSNs on the neutral or alkaline conditions, and responsively release the Au clusters by adjustment of the pH value. • The released Au clusters show a high catalytic activity. Smart delivery systems have received increasing attentions, due to the controllable capturing-releasing of the guests in many applications. Here, we propose a pH-responsive Au cluster capturing-releasing system using the mesoporous silica nanoparticles (MSNs) modified by organic molecular tweezers. The π-π-π stacking have been used to capture and stabilize the Au clusters in the pores of MSNs on the neutral or alkaline conditions, and responsively release and manipulate the Au clusters by adjustment of the pH value. The released Au clusters show high catalytic activity.