Cluster-based coordination polymers (CCPs) have shown promise as capacitors. To investigate the relativity between capacitor performance and crystal structure, herein, five new CCPs based on organophosphorus Strandberg-type clusters were synthesized via in situ hydrothermal reactions at different pH's, namely, (H₂bipy)₂[(C₆H₅PO₃)₂Mo₅O₁₅]·2H₂O (1), (H₂bipy)_1.5[Cu^I(bipy)(C₆H₅PO₃)₂Mo₅O₁₅]·H₂O (2), H₂[Cu^I₂(bipy)_2.5(C₆H₅PO₃)₂Mo₅O₁₅]·2H₂O (3), Na₂[Cu^I₄Cu^II(bipy)₄(C₆H₅PO₃)₂(Mo₅O₁₅)₂]·15H₂O (4), [Cu^II₂(bipy)(H₂O)₄(C₆H₅PO₃)₂Mo₅O₁₅] (5) (bipy = 4,4'-bipyridine). Compound 1 is a zero-dimensional monomer, in which the protonated bipy ligands as countercations combine Strandberg-type clusters by hydrogen bonding and π-π interaction forming a supramolecular layer. Compound 2 represents a unique one-dimensional (1D) channel chain structure linked by intermolecular hydrogen bonding and π-π interaction. Compounds 3 and 4 exhibit the first example of an interdigitated architecture based on organophosphorus Strandberg-type clusters [1D + 1D → two-dimensional (2D) for 3 and 2D + 2D → three-dimensional (3D) for 4]. Compound 5 displays a novel (3,4)-connected 3D microporous framework with (8¹·6²) (8³·6³) topology. Notably, the more complicated structures of compounds 1-5 were obtained with an increase in pH. The isolation of five compounds is beneficial for our systematic understanding of the effect of pH on the assembly of CCPs. Organophosphorus Strandberg-type polyoxometalate clusters were explored as supercapacitor electrode materials for the first time. Compared with other CCPs in this work, compound 5 shows the highest specific capacitance, 160.9 F g^-1, at a current density of 2 A g^-1, and for favorable cycling stability, after 1000 cycles, the retention rate of the capacitance is 95.6% at 10 A g^-1.

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