Design of a thermally stable and highly active SERS optical sensor for the ultrasensitive detection of dye molecules at high-temperature

Surface enhanced Raman spectroscopy (SERS) with both enhanced activity and pronounced thermal stability is very suitable for ultra-sensitive monitoring of thermally assisted chemical bonding/fragmentation reactions in important industrial catalysis. Herein, we report an appealing thermally stable SERS active sensor based on the construction of multiple-branched Au/Ag nanodendrites (NDs). The obtained Au/Ag NDs with tremendous elongated branches and enormous antennas exhibit a much higher SERS activity for dye detection under 785 nm near infrared (NIR) laser irradiation, as compared to as-prepared other reference samples. Meanwhile, the corresponding unique intermetallic synergy can effectively suppress the oxidation of chemically active Ag in a hot environment. It is important that more than 90% SERS activity at room temperature (∼25 ℃) can be well maintained at high temperature (∼170 ℃) within 30 min continuous tests. Thus, it holds great potential for the in-situ SERS monitoring of high-temperature catalytic reactions in the future.