Hydroxyl Group-Abundant TiO2 Semiconductor SERS Sensor toward Polymerization Inhibitor Sensing

One of the most significant challenges faced by semiconductor-based surface-enhanced Raman scattering (SERS) is achieving high-efficiency SERS detection in complex real-world application scenarios. Currently, the analytical applications of semiconductor-based SERS in a practical system inevitably encounter significant difficulties because of the lack of highly efficient charge-transfer (CT) in common semiconductor systems. Here, we present the sensitive detection of trace polymerization inhibitors in olefins using colloidal TiO2 nanocrystals as SERS substrates within minutes, which has important implications for olefin quality monitoring. The detection relies on the formation of a resonance-related CT complex between polymerization inhibitors and colloidal TiO2, resulting in highly efficient CT. As such, this method offers detection limits as low as 0.9 ppm, which is sensitive enough to enable assessment of polymerization inhibitors in commercial olefin products. We envision that this approach will be of great utility for producing and storing high-quality olefins and other important chemicals.