sers and rrs spectral detection of ultratrace sulfite based on ptpd nanoalloy catalytic amplification

At temperature of 75 °c, the ethanol-haucl4 reaction to generate gold nanoparticles is relatively slow (aunps), and the noble metal nanoparticles can catalyze this nanoreaction. sulfite can reduce pdcl2-h2ptcl6 to generate ptpd nanoalloy (ptpd) and strong catalysis to generate red aunps, which has a strong rrs peak at 370 nm. when victoria blue 4r (vb4r) is added, it produced a strong sers peak at 1617 cm−1. we use sers, rrs, absorption spectroscopy, electron microscopy, and other techniques to study the catalytic reaction of ptpd nanoalloy and propose a new mechanism for the nanoalloy catalytic reactions. when the so32−concentration in the system gradually increases, the aunps produced by the catalytic reaction gradually increase and the rrs/sers peak intensity increases linearly. based on the nanoalloy catalytic amplification strategy, a new and sensitive rrs/sers coupled dual-mode detection method for so32− was constructed, with linear range of 0.13–12.1 μg·l−1 and a dl of 0.02 μg·l−1.