Sensitive detection using heterostructure of black phosphorus, transition metal di-chalcogenides and MXene in SPR sensor

This work presents van der Waals heterostructure (vdWh) of Black phosphorus (BP)/Transition metal di-chalcogenides (TMDs)/MXene (Ti 3 C 2 T x ) based highly sensitive novel SPR sensor for biochemical sensing. 2D layered nature of BP, TMDs, and MXene allow them to form van der Waals heterostructure by vertically stacking them together to get exotic electronic and optical properties useful for surface plasmon resonance (SPR) sensing. Unique properties of MXene like its layered architecture, larger surface area, highly accessible hydrophilic surface terminations, chemical stability, smaller work function, and strong light-matter interaction are utilized to enhance the sensitivity of the proposed sensor. The proposed work theoretically analyzes its sensitivity (S) and compares it with other structures. The anisotropic nature of 2D layered BP is used to tune the sensitivity of the proposed sensor. The highest sensitivity of 388 ο /RIU is achieved at 633 nm wavelength for WS 2 tri-layer in the proposed biochemical sensor. The SPs field variation along normal to interface validates the highest sensitivity obtained for the proposed heterostructure SPR sensor through field plots. These results will open an innovative route to design and develop such an SPR biochemical sensor practically, with fabrication possibilities of MXene with TMDs and BP.