Few-layer Ti^sub 3^C^sub 2^T^sub x^ MXene: A promising surface plasmon resonance biosensing material to enhance the sensitivity

In this contribution, a novel surface plasmon resonance (SPR) biosensor with few-layer Ti3C2Tx MXene to enhance the sensitivity is proposed. Few-layer Ti3C2Tx MXene is coated on the surface of metals thin film to act as a protective layer and further to improve the sensitivity. The results show that the sensitivity enhancements at λ = 633 nm are 16.8%, 28.4%, 46.3% and 33.6% for the proposed SPR biosensors based on Au with 4 layers Ti3C2Tx, Ag with 7 layers Ti3C2Tx, Al with 12 layers Ti3C2Tx and Cu with 9 layers Ti3C2Tx, respectively. Moreover, we have discussed the sensitivity of the proposed Au-based SPR biosensor with monolayer Ti3C2Tx MXene works at λ = 532 nm, the result shows that the sensitivity can reach 224.5°/RIU. Our contributions reveal potential applications of few-layer Ti3C2Tx MXene as a new type of biosensing material, and it is therefore anticipated that Ti3C2Tx MXene and other 2D MXene nanomaterials could find promising applications in SPR biosensors.