Nanocellulose-Based Proton Exchange Membranes with Excellent Dimensional Stability, Superior Mechanical Properties, and High Proton Conductivity via Composite MOF@CNT

H groups; the incorporation of CNFs/CNCs (CCs) further enhanced the stability of the S-UIO-66 dispersion, and more unobstructed proton conduction pathways were established in the membrane. As a consequence, the resulting PEM (CC/S-UIO-66@CNT-5) composite developed superior mechanical properties (93 MPa) and high proton conductivities (0.105 S/cm at 80 °C and 100% RH and 27 mS/cm at 80 °C and 33% RH). In addition, battery performance tests showed promising potential for its application in fuel cells.