•A novel SERS active substrate was prepared by combining a two-step EFAD with annealing.•The Raman signals of R6G were significantly enhanced in our substrates.•The detection limit of 10−9 M for R6G was achieved.•The two-step EFAD method provides a novel pathway for the development of future SERS sensor chips.A highly stable substrate used for surface-enhanced Raman scattering (SERS) was fabricated by combining two-step electric field-assisted diffusion (EFAD) with subsequent annealing. The samples were characterized by UV/Vis spectroscopy, X-ray diffraction analysis (XRD), X-ray photoelectron spectra (XPS), atomic force microscopy (AFM) and transmission electron microscopy (TEM). The SERS activity of these substrates was evaluated by using Rhodamine 6G (R6G) as the probe molecule. The results showed that the Raman signals were significantly enhanced in our substrates. The reverse EFAD process was applied to induce larger silver NPs or aggregates formed in the glass, leading to a stronger SERS signal. The enhancement factor about 106 and the detection limit of 10−9 M for R6G were achieved. This method is also very simple and cost-effective and provides a novel pathway for the development of future SERS sensor chips.

•TiN NRs were prepared using a hydrothermal process followed by nitridation.•The Raman signal of R6G was significant enhanced in TiN NRs substrates.•The detection limit with the concentration of 10−6 M for R6G was achieved in our substrates.TiN nanorod arrays (NRs) were prepared using a hydrothermal process followed by nitridation in ammonia atmosphere. The fabricated TiN NRs were characterized by UV–vis spectroscopy, X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The Surface-enhanced Raman scattering (SERS) activity of these substrates was evaluated by using Rhodamine (R6G) and crystal violet (CV) as the probe molecules. Results showed that TiN NRs prepared at 900 °C exhibited the strongest Raman enhancement performance. The average sizes of the TiN NRs were 57 nm. The TiN NRs had an absorption peak around 524 nm, which related to surface Plasmon resonance. Compared to the CV molecules, the R6G molecules can obtain a higher enhancement in our substrate. The enhancement factor ((8.9 ± 0.2) × 103) and the R6G detection limit (10−6 M) were achieved. The results showed that the TiN NRs are a kind of promising materials as SERS sensor.

Soda-lime glasses were treated by electric field-assisted diffusion (EFAD) process. The mechanical properties and structural evolution on both glass anode and cathode surfaces were investigated, respectively. It was found that the EFAD resulted in the formation of a Na depletion layer on anode surface, which caused the relaxation of the glass anode surface network and the formation of a number of defects. Correspondingly, the hardness and flexural strength declined in anode surface compared to that of the original glass. On the other hand, the EFAD also created a compressive layer on cathode surface, causing the improvement of the hardness and flexural strength on cathode surface. The defected structure could be reconstructed by additional annealing process.

Ag nanocrystals embedded silicate glass was successfully prepared by solid-state field-assisted diffusion, combined with post-annealing process. The changes of glass structure, the chemical states of Ag and O species, the microstructures of Ag nanocrystals, as well as the properties of optical absorption were studied for the as-diffused and post-annealed samples. The result showed that after the field-assisted diffusion process, some Ag+ ions replaced the alkaline ions in the glass matrix. Meanwhile, other Ag+ ions were reduced to Ag0 atoms occupying the interspaces of the network and Ag0 atoms clusters with small size were formed. This caused the relaxation of the glass network and the deceasing of force constant for Si–O linkage. After post-annealing process, bigger size of Ag nanoparticles were formed, which caused the peak corresponding to the surface plasmon resonance (SPR) observed.