Strategically Hierarchical Improvement of Superprotonic Conductivity in Stable Metal-Organic Framework System
Seeking the proton-exchange membranes (PEMs) with high proton conductivity and long-term durability is highly important to the development of fuel cells. Herein, an efficient and feasible strategy that features different proton sources and hopping sites modifications on stable UiO-66-NH2 framework for hierarchically improving proton conductivity is demonstrated. As a result, IM-UiO-66-AS shows the highest superprotonic conductivity of 1.54 × 10-1 S cm-1 (80 °C, 98% RH) and outstanding long-term durability of at least 100 h, which have surpassed all the reported proton-conducting MOFs materials without guest loading. Furthermore, the manufactured membrane still can maintain high proton conductivity with 1.19 × 10-2 S cm-1 associated with continuous work of at least 40 h under the same conditions, suggesting the great potential for further device application.