The capacitor performance of newly synthesized crystalline POMOFs was higher than those of the majority of reported POMOF-, state-of-the-art MOF- and POM-based materials.

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state-of-the-art electrocatalysts for HER, but their potential utilization is significantly impeded because of the scarcity and high-price. [5,6] Thus, a promising avenue is to create non-noble electrocatalysts with high-efficiency, low-cost, and long-durability for boosting the HER. In recent years, the non-noble electrocatalysts, such as carbides, [7-10] nitrides, [11-15] oxides, [16-19] phosphides, [20-28] sulfides, [29-37] selenides, [38,39] and carbonbased materials [3,40] have been explored for HER to substitute Pt-group metals, and prominent achievements have achieved. Among these newly developed electrocatalysts, molybdenum disulfide (MoS 2) has attracted tremendous attention as one of promising nonprecious metal candidates for HER due to its unique grapheneshaped 2D structure, proper ΔG H* , low cost, and simple synthesis method. [29-34] However, MoS 2 has two main bottlenecks, including few

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[CuI(bipy)­(C6H5PO3)2Mo5O15]·H2O (2), H2[CuI 2(bipy)2.5(C6H5PO3)2Mo5O15]·2H2O (3), Na2[CuI 4CuII(bipy)4(C6H5PO3)2(Mo5O15)2]·15H2O (4), [CuII 2(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.