Prof. Weimin Xuan and co-workers have synthesized a series of porous polyoxometalate–organic frameworks assembled from trigonal tecton tris(4-(4H-1,2,4-triazol-4-yl)phenyl)amine cations and Keggin-type polyoxometalate anions with three different valence states—i.e., [PW₁₂O₄₀]^3-, [SiW₁₂O₄₀]^4-, [BW₁₂O₄₀]^5-—via electrostatic interactions and [C–H···anion] hydrogen bonds. These frameworks after post-synthetic modification via sequentially incorporating imidazolium and sulfonates exhibit high protonic conductivity of up to 7.04 × 10^-2 S cm^-1 at 85 °C and 98% relative humidity, providing a promising platform for high-performance fuel-cell membranes.