고분자-귀금속 나노결정 하이브리드 소재의 합성과 응용

Abstract

Metal nanocrystals have excellent physical, chemical and optical properties. Hydrogel composites using metal nanocrystals are used in a wide variety of applications including sensors, catalysts, and tissue engineering in various related fields such as chemistry, physics, and biotechnology due to their nanoscale optical, electrical, and catalytic properties. In this study, we demonstrate a significant improvement in the chemical stability of silver nanoprisms by developing a novel surface immobilization method based on a single-step water-based process. Specifically, Ag nanoprism has a triangular two-dimensional plate-like structure and has a strong and adjustable in-plane dipole resonance mode in the near-infrared and visible regions. Tetramethylethylenediamine was used as an organic capping ligand, and Tetramethylethylenediamine-treated silver nanoprisms maintained their original shape even when exposed to diverse powerful etchants including H2O2, Cl-, and Br-. The sharp edges of the nanoprisms were spontaneously etched in the presence of I-, and this etching resulted in rapid changes in the LSPR properties. We also develop a facile system to fabricate novel continuous flow reactors for the catalytic conversion of organic matter in water by mixing concepts from nanocomposite hydrogels and flow chemistry. Compared to batch reaction techniques in catalysis, continuous flow reaction provides appealing and significant characteristics, offering a novel paradigm for heterogeneous catalysis. We adopt a seed-mediated growth approach in island growth mode to synthesize plasmonic nanohybrids in which dozens of AuAg alloy nanoislands are formed on a single Pd nanoplate. A one-dimensional hydrogel embedded with these nanoislands was synthesized and a continuous flow reactor was fabricated in a transparent tube by forming channels inside the hydrogel. The experimental results show that the catalytic performance of the flow reactor can be efficiently regulated by changing the mechanical properties of the hydrogel, such as the crosslinking density, flow rate, and characteristics of the inner channels. Under the optimized conditions, excellent catalytic activity with a conversion rate exceeding 95% was obtained.