Highly Sensitive Surface Plasmon Resonance Sensor Modified With 2D Ti₂C MXene for Solution Detection

Abstract

Two-dimensional (2D) Ti2C MXene has great prospects in many fields of biotechnology and biosensing owning to their highly active 2D surfaces, in this work, we demonstrate a high sensitivity surface plasmon resonance (SPR) sensor modified by the 2D Ti2C nanosheets overlayer. Our experimental results show that the performances of the SPR sensor are closely related to the thickness of 2D Ti2C nanosheets, and the proposed design gives the wavelength sensitivity of 3579.6 nm/RIU, which are 79% higher than the SPR sensor without Ti2C overlayer. In addition, the Ti2C covered SPR sensor is capable of detecting low concentrations of heavy metal ions, our results show that the maximum concentrate sensitivities are 3.788 nm/ $\mu \text{g}$ /L, 5.308 nm/ $\mu \text{g}$ /L and 3.233 nm/ $\mu \text{g}$ /L for Pb2+, Cr2+ and Hg2+ ions, and the corresponding detection limits are 79.2 ng/L, 56.5 ng/L and 92.8 ng/L, which are lower than the international medical standards. Our results pave the way to realize high sensitivity biosensor and environmental pollution detection.