1 research outputs found
Biomimetic Ag/ZnO@PDMS Hybrid Nanorod Array-Mediated Photo-induced Enhanced Raman Spectroscopy Sensor for Quantitative and Visualized Analysis of Microplastics
Microplastics are persistent pollutants that accumulate
in the
environment and can cause serious toxicity to mammals. At present,
few technologies are able to quantitatively detect chemicals and provide
morphological information simultaneously. Herein, we developed a dragonfly-wing-mimicking
ZnO nanorod array decorated with AgNPs on polydimethylsiloxane (PDMS)
as a surface-enhanced Raman spectroscopy (SERS) and photo-induced
enhanced Raman spectroscopy (PIERS) substrate for trace analysis of
microplastics. The Ag/ZnO@PDMS hybrid nanorod array endows the sensor
with high sensitivity and signal repeatability (RSD ∼ 5.89%),
ensuring the reliable quantitative analysis of microplastics. Importantly,
when the noble metal–semiconductor substrate was pre-radiated
with ultraviolet light, a surprising PIERS was attained, achieving
an additional enhancement of 11.3-fold higher than the normal SERS
signal. By combining the PIERS technology with the “coffee
ring effect”, the sensor successfully discerned microplastics
of polyethylene (PE) and polystyrene (PS) at a trace level of 25 μg/mL
even with a portable Raman device. It was capable of identifying PS
microspheres in contaminated tap water, lake water, river water, and
seawater with detection limits of 25, 28, 35, and 60 μg/mL,
respectively. The recovery rates of PS microspheres in four water
environments ranged from 94.8 to 102.4%, with the RSD ranging from
2.40 to 6.81%. Moreover, quantitative and visualized detection of
microplastics was readily realized by our sensor. This portable PIERS
sensor represents a significant step toward the generalizability and
practicality of quantitative and visual sensing technology