Temperature- and pH-tunable plasmonic properties and SERS efficiency of the silver nanoparticles within the dual stimuli-responsive microgels
writer：劉曉云，王秀琴，查劉生等
keywords：microgels， dual stimuli-responsive ，silver nanoparticles ，SERS
source：期刊
specific source：J. Mater. Chem. C, 2014, 2, 7326–7335
Issue time：2014年
The silver nanoparticle (AgNP)-loading microgels with an interpenetrating polymer network structure
composed of separately cross-linked poly(acrylic acid) and poly(N-isopropylacrylamide) were prepared
through an in situ reduction reaction of silver ions coordinated into their networks. The temperature- or pHdependent
hydrodynamic diameters measured using dynamic laser light scattering show that the hybrid
microgels produced has dual pH and temperature stimuli-responsive properties with little mutual
interference between the temperature- and pH-responsive components. The localized surface plasmon
resonance wavelength of the AgNPs inside the microgels can be reversibly tuned with temperature changing
from 20 C to 45 C or pH values changing from 3.0 to 7.0. When the hybrid microgels were used as the
surface-enhanced Raman scattering (SERS) substrates for probing minute amounts of 4-mercapto benzoic
acid in an aqueous solution, its SERS intensity is remarkably increased with pH value lowering from 7.0 to 3.0
or temperature rising from 20 C to 45 C. If the two stimuli are simultaneously exerted, the SERS intensity is
greatly elevated. The temperature and pH value measuring results show that the hybrid microgels are able to
be utilized as SERS microsensors for measuring both pH value and the temperature of their surroundings