Photoinduced Charge Transfer Empowers Ta₄C₃ and Nb₄C₃ MXenes with High SERS Performance

This study introduces two-dimensional (2D) Ta₄C₃ and Nb₄C₃ MXenes as outstanding materials for surface-enhanced Raman scattering (SERS) sensing, marking a significant departure from traditional noble-metal substrates. These MXenes exhibit exceptional SERS capabilities, achieving enhancement factors around 10⁵ and detection limits as low as 10^-7 M for various analytes, including environmental pollutants and drugs. The core of their SERS functionality is attributed to the robust interfacial photoinduced charge-transfer interactions between the MXenes and the adsorbed molecules. This deep insight not only advances our understanding of MXene materials in SERS applications but also opens new avenues for developing highly sensitive and selective SERS sensors. The potential of Ta₄C₃ and Nb₄C₃ MXenes to revolutionize SERS technology underscores their importance in environmental monitoring, food safety, and beyond.