[en] Highlights: • Carbon-coated pyrophosphate materials AMoP2O7 (A = Li and Na) were prepared via freeze- drying method. • BVEL analysis revealed the remarkable difference in the alkali diffusion behaviors of two AMoP₂O₇ polymorphs. • LiMoP₂O₇ shows the superior electrochemical activity towards de/intercalation of Li⁺ and Na⁺ ions compared with NaMoP₂O₇ - Abstract: The carbon-coated single-phase samples of the pyrophosphates AMoP₂O₇ (A = Li and Na) were synthesized using freeze-drying followed by annealing in a sealed silica tube with the Fe/FeO getter. The Rietveld refinement of the X-Ray powder diffraction data proved both structures are built up as a network of corner-linked MoO₆ octahedra and P₂O₇ groups with A-cations located in the open tunnels running along the [100] (LiMoP₂O₇) and [101] (NaMoP₂O₇) directions. The bond valence energy landscapes (BVEL) analysis revealed three-dimensional pathways of alkali-ion migration with significantly different activation energies (0.8 eV for LiMoP₂O₇ and 4.5 eV for NaMoP₂O₇) anticipating LiMoP₂O₇ to exhibit faster Li⁺ diffusion and better electrochemical characteristics. Both materials displayed electrochemical activity in Li- and Na-cells with reversible capacities of ∼20 mA h g⁻¹ for NaMoP₂O₇ and more than 70 mA h g⁻¹ for LiMoP₂O₇, being in a good agreement with the BVEL results.