Evaluating the delamination process in the synthesis of MXenes (
Two-Dimensional Transition Metal carbides and nitrides) is critical for their development and application. However, preparing large, defect-free MXene flakes with high yields is challenging. Here, a power-centered delamination (PFD) strategy is demonstrated that can improve the delamination efficiency and yield of large Ti3C2Tx MXene nanosheets through repeated precipitation and vortex oscillation processes. According to the protocol, Ti3C2Tx MXene has a colloidal concentration of 20.4 mg ml-1, which can be achieved after five PFD cycles, and a 61.2% Ti3C2Tx nanosheet free of base surface defects is obtained, 6.4 times higher than that obtained using ultrasonic stripping. Both nanothin devices and self-supporting films exhibit excellent electrical conductivity (approximately 25,000 and 8260 S cm-1 for 1.8 nm thick monolayers and 11 µm thick films, respectively). Hydrodynamic simulations show that the PFD method can effectively concentrate shear stress on the surface of the unstripped material, resulting in the stripping of the nanosheets. Large MXene nanosheets synthesized by PFD exhibit excellent electrical conductivity and electromagnetic shielding (shielding efficiency per unit volume: 35 419 dB cm 2 g-1). Therefore, PFD strategy provides an effective way to prepare high-performance single-layer MXene nanosheets with large area and high yield
