Solid electrolytes have attracted much attention due to their great prospects
in a number of energy- and environment-related applications including fuel
cells. Fast ion transport and superior mechanical properties of solid electrolytes
are both of critical significance for these devices to operate with high
efficiency and long-term stability. To address a common tradeoff relationship
between ionic conductivity and mechanical properties, electrolyte membranes
with proton-conducting 2D channels and nacre-inspired architecture
are reported. An unprecedented combination of high proton conductivity
(326 mS cm−1 at 80 °C) and superior mechanical properties (tensile strength
of 250 MPa) are achieved due to the integration of exceptionally continuous
2D channels and nacre-inspired brick-and-mortar architecture into one materials
system. Moreover, the membrane exhibits higher power density than
Nafion 212 membrane, but with a comparative weight of only ≈0.1, indicating
potential savings in system weight and cost. Considering the extraordinary
properties and independent tunability of ion conduction and mechanical
properties, this bioinspired approach may pave the way for the design of nextgeneration
high-performance solid electrolytes with nacre-like architecture.