Plasmon-induced hot electrons trigger polymerization reactions on the surface of plasmonic nanocrystals at low temperatures

Abstract

Metal nanocrystals exhibit excellent plasmonic responses in the visible wavelength range and generate energetic hot electrons on their surfaces. This energy can be transferred and can trigger various chemical reactions. Theoretically, energetic hot electrons on the surface of plasmonic nanocrystals can replace thermal energy or high-energy substances to provide energy for polymerization. Here, three different nanocrystals with plasmonic responses in the visible range are used to study hot electron-induced polymerization at nanocrystal surfaces. The results showed that this polymerization reaction is less sensitive to temperature changes than general chemical reactions, such as oxidation of the nanocrystal surface. The number and energy of hot electrons on the nanocrystal surface can be adjusted by changing the wavelengths of the excitation light, thereby changing the rate of polymerization reactions occurring on them. The results also showed that the effect of the morphology (surface area/volume ratio) and composition (synergistic effect) of heterogeneous nanocrystals on enhanced catalytic and photocatalytic performance can be eliminated by lowering the reaction temperature to −12 °C. This study provides an environmentally friendly polymer formation method to overcome the serious pollution problems caused by traditional polymer formation methods.