• • Nanoconfined water between GO and MXene nanoplatelets eliminates capillary contraction, achieving highly aligned lamellar structure with real in-plane isotropy.
• • The resulting πBMG sheets exhibit tensile strength of 1870 ± 20 MPa and Young's modulus of 98.7 ± 1.1 GPa, outperforming conventional graphene-based sheets and carbon fiber composites.
• • The process involves continuous vacuum filtration to trap atomically thin water layers, followed by reduction and π-bridging cross-linking, ensuring interlayer spaces remain solvent-filled.
• • This strategy provides a scalable route to fabricate high-performance layered nanocomposites with isotropic properties, addressing the long-standing bottleneck of capillary-induced defects.