High Sensitivity Surface Plasmon Resonance Sensor Based on Two-Dimensional MXene and Transition Metal Dichalcogenide: A Theoretical Study

• Main Authors: Yi Xu, Yee Sin Ang, Lin Wu, Lay Kee Ang
• Format: Article
• Language: English
• Published: MDPI AG 2019-01-01
• Series: Nanomaterials
• Subjects: MXene; Ti₃C₂T<i>_x</i>; transition metal dichalcogenides; surface plasmon resonance; sensitivity
• Online Access: https://www.mdpi.com/2079-4991/9/2/165
• ISSN: 2079-4991

MXene, a new class of two-dimensional nanomaterials, have drawn increasing attention as emerging materials for sensing applications. However, MXene-based surface plasmon resonance sensors remain largely unexplored. In this work, we theoretically show that the sensitivity of the surface plasmon resonance sensor can be significantly enhanced by combining two-dimensional <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>Ti</mi> <mn>3</mn> </msub> <msub> <mi mathvariant="normal">C</mi> <mn>2</mn> </msub> <msub> <mi mathvariant="normal">T</mi> <mi>x</mi> </msub> </mrow> </semantics> </math> </inline-formula> MXene and transition metal dichalcogenides. A high sensitivity of <inline-formula> <math display="inline"> <semantics> <msup> <mn>198</mn> <mo>∘</mo> </msup> </semantics> </math> </inline-formula>/RIU (refractive index unit) with a sensitivity enhancement of 41.43% was achieved in aqueous solutions (refractive index &#8764;1.33) with the employment of monolayer <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>Ti</mi> <mn>3</mn> </msub> <msub> <mi mathvariant="normal">C</mi> <mn>2</mn> </msub> <msub> <mi mathvariant="normal">T</mi> <mi>x</mi> </msub> </mrow> </semantics> </math> </inline-formula> MXene and five layers of <inline-formula> <math display="inline"> <semantics> <msub> <mi>WS</mi> <mn>2</mn> </msub> </semantics> </math> </inline-formula> at a 633 nm excitation wavelength. The integration of <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>Ti</mi> <mn>3</mn> </msub> <msub> <mi mathvariant="normal">C</mi> <mn>2</mn> </msub> <msub> <mi mathvariant="normal">T</mi> <mi>x</mi> </msub> </mrow> </semantics> </math> </inline-formula> MXene with a conventional surface plasmon resonance sensor provides a promising approach for bio- and chemical sensing, thus opening up new opportunities for highly sensitive surface plasmon resonance sensors using two-dimensional nanomaterials.