Application of Titanium-Carbide MXene-Based Transparent Conducting Electrodes in Flexible Smart Windows

Among various available materials used in transparent and flexible devices, MXenes are attracting attention as a brand-new candidate in this category. Ti(3)C(2)Tx MXene as a 2D material has exceptional properties, making it a potential material having numerous applications in different areas. Because of its high conductivity, it can be used in transparent conducting electrodes (TCEs). In this study, the MXenes etched by highly concentrated acid at 50 degrees C,were spin-coated on polyethylene terephthalate (PET) film and annealed at moderate temperatures up to 170 degrees C. The adhesion of MXene to PET was found to be remarkably improved by annealing. These TCEs exhibited a sheet resistance of similar to 424 Omega/sq. and transmittance of similar to 87%. The aging stability of MXene-coated PET films against oxidation under ambient conditions was studied up to 28 days and resistance change was found similar to 30% during this period. The flexibility test showed low bending resistance change (similar to 1.5%) at 1000th cycle and cumulative resistance change of similar to 20% at a bending radius of similar to 3.9 mm after 1000 cycles. These transparent, flexible, and conducting electrodes were used to fabricate polymer dispersed liquid crystal (PDLC)based flexible smart windows. The smart windows fabricated by curing PDLC mixture sandwiched between the MXene electrodes were also found flexible in ON/OFF states. The MXene-based flexible smart windows resulted in good opacity in the OFF state and high transparency in the ON state, exhibiting low threshold voltage <10 V and high transmittance similar to 80% at 60 V. The flexible smart windows operated normally even at similar to 4 mm bending radius.