Highly sensitive VOC gas sensor employing deep cooling of SERS film

Abstract

The potential of surface‐enhanced Raman spectroscopy (SERS) as a highly sensitive and selective gas sensor was investigated experimentally. Especially, the relation between the temperature of a SERS film and gas adsorption or signal intensity was observed systemically and quantitatively, from which the enhancement of gas adsorption and signal intensity by up to 40 times was observed with the SERS film temperature of approx. −80 °C, which corresponds to theoretical anticipation and leads to detection sensitivity defined by limit of detection in 3σ ~1 ppb in case of benzene gas within 2‐min acquisition time. For SERS, Ag nanorod array films functionalized by propanethiol and a spectrometer with a fiber Raman probe and 785‐nm pump laser were employed. The target volatile organic compound gas was benzene. The detection sensitivity of the SERS sensor was ~1 ppm at room temperature within 2‐min acquisition time.

Ag Nanorods-Based Surface-Enhanced Raman Scattering: Synthesis, Quantitative Analysis Strategies, and Applications

“…SERS can also expand its utilization from the aquatic environment to the vapor phase which should find applications in chemical sensing for volatile organic chemicals and explosives (Shah et al, 2013; Kreno et al, 2014; He et al, 2015; Ma et al, 2016b; Oh et al, 2018). Ma et al designed a real-time gas sensing platform for 2-naphthalenethiol (2-NaT) and 2-mercaptopyridine (2-MPy) employing AgNRs-HfO 2 substrates (Ma et al, 2016b).…”

“…Thus, various molecules modifications on plasmonic materials were explored by researchers, such as metal–organic frameworks and thiol compounds (Lee et al, 2019). For example, Oh et al fabricated AgNRs and functionalized it with propanethiol (Oh et al, 2018). Due to the physical adsorption of benzene molecules to propanethiol, SERS spectra of benzene in vapor phase were successfully observed on substrates and the detection ability of this sensor was found ~1 ppm at room temperature with 120 s acquisition time.…”

Recent advances in linear and nonlinear Raman spectroscopy. Part XIII

“…Oh and co‐workers explored the potential of SERS as a highly sensitive and selective gas sensor. Of special focus was the relation between the temperature of the SERS film and gas adsorption from which the enhancement of gas adsorption and signal intensity by up to 40 times was observed . Piergies et al were able to identify adsorption of the pattern of erlotinib onto silver NPs using SERS.…”

“…Of special focus was the relation between the temperature of the SERS film and gas adsorption from which the enhancement of gas adsorption and signal intensity by up to 40 times was observed. [45] Piergies et al were able to identify adsorption of the pattern of erlotinib onto silver NPs using SERS. They found that the phenyl ring interacts rather weakly with the AgNPs and is oriented perpendicularly onto the surface, whereas the quanizoline moiety only participates in this interaction with a tilted orientation.…”

Active site-dominated electromagnetic enhancement of surface-enhanced Raman spectroscopy (SERS) on a Cu triangle plate

“…The Raman scattering signals carrying the ngerprint information of molecules with high spectral resolution and sensitivity can be applied in the elds of catalysis, 1 sensing, [2][3][4][5][6] chemical analysis, [7][8][9] environment monitoring. 10 However, the weak Raman scattering intensity of pure substances limits its scope of comprehensive application. Surface-enhanced Raman spectroscopy (SERS) is a powerful and effective non-destructive strategy to further strengthen Raman scattering.…”