Improved Charge Transfer and Hot Spots by Doping and Modulating the Semiconductor Structure: A High Sensitivity and Renewability Surface-Enhanced Raman Spectroscopy Substrate

Abstract

Here, we develop a new method to improve the surface-enhanced Raman spectroscopy (SERS) activity of ZnO using Mg doping combined with noble metals. Highly aligned silver nanoparticles (AgNPs) decorated on an array of Mg-doped ZnO (MZO@Ag) were fabricated. Using rhodamine 6G as the probe molecule, SERS indicated that the MZO@Ag substrate possesses perfect sensitivity, homogeneity, and chemical stability. The enhancement mechanism of this substrate was analyzed in detail, and finite-difference time-domain (FDTD) simulations were used to examine “hot spot” distribution which generated gaps between the balls, the rods, and the stems. FDTD simulation calculated (E/E 0)4 to be 2.5 × 106. Furthermore, the prepared substrates could degrade the target molecules in situ irradiated by visible light irradiation over the course of 40 min and then efficiently recover detectability through a recycling process. Our substrates were easy to fabricate, self-cleaning, and reusable. They are expected to provide new opportunities for the use of SERS in biological sensors, biomedical diagnostics, and food safety.

Monitoring the charge-transfer process in a Nd-doped semiconductor based on photoluminescence and SERS technology

“…In general, the enhanced magnitude of SERS is associated with two mechanisms. One is the electromagnetic mechanism, which is related to the localized surface plasmon resonance of the metal nanoparticles (NPs) 4 . The other is the chemical mechanism, which mainly originates from the charge transfer (CT) between adsorbed molecules and SERS-active substrates 5 .…”

Toward low-cost and sustainable SERS substrate: novel ultrasensitive AMS5 nanoflowers

“…The peaks at 1576 cm −1 and 1311, 1364, 1511, 1648 cm −1 corresponded to CvC stretching and C-C stretching, respectively. 3 The peak intensity changes regularly with the doped Ag concentration. Fig.…”

“…Surface-enhanced Raman scattering (SERS) has received increasing attention in recent years due to its ultrahigh sensitivity and unique spectral fingerprint, showing wide applications in the fields of analytical chemistry and environmental science. [1][2][3][4] In the past ten years, many methods have been tried to improve the activity of SERS substate materials. [5][6][7][8][9][10][11] Despite the fact that these SERS signal have been greatly enhanced, their high cost, poor uniformity, and storage problems limit their commercial application.…”

Recyclable Surface-Enhanced Raman Scattering Substrate-Based Sensors for Various Applications

“…Additionally, many metal/semiconductors can be excited by visible light. − For example, highly aligned silver nanoparticles decorated on an array of Mg-doped ZnO were fabricated by Yao et al The prepared substrate could degrade the target molecules in situ irradiated by visible light irradiation for 40 min and then recover some detectability through a recycling process. Qiu et al developed a flexible SERS substrate by integrating graphitic‑carbon-nitride nanosheets and Ag nanospheres and this SERS substrate demonstrates good reusability via visible-light photodegradation .…”