Functional MXene Inks for Printed Electronics: Chemistry, Rheology, and Devices

MXene-based functional inks have emerged as a promising platform for printed electronics by combining high electrical conductivity, tunable surface chemistry, and solution processability. This review establishes a unified framework linking MXene synthesis, surface engineering, ink rheology, printing behavior, and device performance across diverse additive manufacturing technologies. Particular emphasis is placed on how chemical functionalization, composite design, and interfacial engineering influence colloidal stability, printability, and functionality. By elucidating structure-ink-process-property relationships, the review reveals how MXene chemistry and rheology govern printed microstructure and performance in sensors, energy-storage devices, and electromagnetic interference shielding systems. Despite rapid progress, widespread implementation remains constrained by three interconnected challenges: ensuring long-term chemical and colloidal stability, achieving printability without sacrificing electrical transport, and establishing scalable, reproducible manufacturing routes. Future advances will depend on oxidation-resistant formulations, manufacturing-aware rheological design, sustainable processing strategies, and standardized evaluation protocols. These developments provide a roadmap for translating MXene inks from laboratory-scale demonstrations to reliable, high-performance flexible and multifunctional electronic systems.