A research team at the Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS), has developed an external electric-field strategy that dramatically enhances the sensitivity of MXene-based SERS sensors. The findings were published in Matter.

The research was led by Prof. Yong YANG and Assoc. Prof. Yusi PENG of the Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS). Weida ZHANG is the first author of the paper.

Surface-enhanced Raman scattering (SERS) is a powerful technique for detecting trace amounts of molecules, with applications in chemical sensing, environmental monitoring, and biomedical diagnostics. However, many non-metallic SERS substrates still suffer from limited enhancement capability, making it difficult to achieve reliable, order-of-magnitude improvements in sensitivity.

To overcome this challenge, the team applied a stable external electric field to bimetallic Ti₂TaC₂ MXenes after the fabrication of SERS substrates. This active modulation strategy electrically tailors the near-Fermi electronic structure, carrier distribution, and surface plasmon response of the material, cooperatively amplifying both photoelectric charge transfer and electromagnetic enhancement—two key mechanisms that boost SERS signals.

Under the combined effect of 532-nm laser excitation and a 300 V external field, the Ti₂TaC₂ MXene substrates achieved an ultra-low detection limit of 10⁻¹³ M for rhodamine 6G, a common dye molecule. This represents a three-order-of-magnitude improvement over laser excitation alone, demonstrating the power of the electric-field modulation strategy.

This work establishes an electrically programmable design paradigm for SERS substrates, enabling the charge-transfer and electromagnetic enhancement pathways to be precisely modulated. More broadly, the developed strategy could be extended to other quasi-metallic or semiconductor materials, providing a practical route to tunable, high-sensitivity, non-metal SERS sensors and advancing their use in chemical sensing, environmental monitoring, and biomedical detection.

Figure 1. Schematic illustration of electric-field modulation in a bimetallic MXene SERS substrate and the cooperative enhancement of charge-transfer and plasmonic pathways.

Article Link:https://doi.org/10.1016/j.matt.2026.102921

Contacts: Yusi Peng and Yong Yang

Shanghai Institute of Ceramics, Chinese Academy of Sciences

E-mail: pengyusi@mail.sic.ac.cn; yangyong@mail.sic.ac.cn

Published online: October 7, 2026.