Unveiling the Roles of Fluoroalkylated-Dopamine Functionalization in Dispersion Stability of MXene Organic Inks and...

Ti₃C₂T_x (MXene) has emerged as a promising material for printed energy electronics, owing to its high conductivity and intrinsic hydrophilicity. However, achieving both long-term stability and high electrochemical activity in MXene inks remains challenging. Here, we introduce a surface functionalization strategy using alkylated 3,4-dihydroxy-L-phenylalanine (ADOPA, AD) to prepare high-quality AD-MXene organic inks suitable for inkjet printing. First-principles and molecular dynamics simulations reveal that ADOPA molecules strongly anchor onto MXene surfaces through hydrogen bonding, while the incorporated fluoroalkyl chains expand interlayer spacing, enhance solvent compatibility, and passivate defect sites, thereby substantially promoting dispersion stability of inks. Micro-supercapacitors (MSCs) printed from AD-MXene inks exhibit outstanding performance, delivering an areal capacitance of 45.46 mF cm^{- 2}, a volumetric capacitance of 857.33 F cm^{- 3}, and an energy density of 11.10 mWh cm^{- 3} at a power density of 359.44 mW cm^{- 3}, along with 95.48% capacitance retention after 10 000 cycles and excellent mechanical flexibility. Kinetic analysis further indicates that AD-MXene electrodes exhibit higher capacitive contributions than pristine MXene counterparts, reflecting superior ion transport, adsorption, and surface charge storage. This work demonstrates the effectiveness of molecular functionalization in enabling stable MXene inks and scalable, high-performance energy storage devices.