A new coordination polymer, (Hbpe)(Hbpe){[Cu(pzta)(HO)][PWO]}·5HO (1) (pztaH = 5-(2-pyrazinyl) tetrazolate, bpe = bis(4-pyridyl)ethylene), was synthesized by the hydrothermal method. The structure was determined by single crystal X-ray diffraction analyses and further characterized by the SEM, EDS, BVS, FTIR, and PXRD techniques. In 1, the [PWO] (PW) clusters as bidentate connectors link [Cu(pzta)(HO)] dinuclear copper(ii) complexes to form inorganic-organic chains. These chains and the [Hbpe] counter-cations are fused together via hydrogen bonding to form a 3D supramolecular architecture. While 1 was employed as the electrode in a supercapacitor, the cycling stability (90.7% capacitance retention after 1000 circles) and specific capacitance (168 F g at a current density of 5 A g) of the 1-based electrode are better than those of the parent α-KPWO-based electrode, demonstrating more outstanding electrochemical performances of 1. Besides, the 1-based electrode showed excellent electrocatalytic activities towards the reduction of HO and KIO.

Electrodes with rationally designed hybrid nanostructures can offer many opportunities for the enhanced performance in electrochemical energy storage. In this work, hierarchical ZnCo 2 O 4 /Polypyrrole (PPy) nanostructures on Ni foam were rationally designed and successfully fabricated through a facile two-step method and were directly used as an integrated electrode for supercapacitors. The novel nanoscale morphology has been proven to be responsible for their excellent capacitive performances. When used as electrodes in supercapacitors, the hybrid nanostructures demonstrated prominent electrochemical performances with a high specific capacitance (1559 F/g at a current density of 2 mA/cm 2 ), a good rate capability (89% when the current density increases from 2 to 20 mA/cm 2 ), and a good cycling ability (90% of the initial specific capacitance remained after 5000 cycles at a high current density of 10 mA/cm 2 ). Moreover, the high specific energy density is 30.9 Wh/kg at a current density of 2 mA/cm 2 in a two-electrode system. The excellent electrochemical performance of hierarchical ZnCo 2 O 4 /PPy nanostructures can be mainly ascribed to the enhanced adherent force between electrode materials and Ni foam to hold the electrode fragments together by means of ZnCo 2 O 4 nanowires, the good electrical conductivity of PPy, the short ion diffusion pathway in ordered porous PPy nanofilms and ZnCo 2 O 4 nanowires.*Corresponding author E-mails: fyzf318@163.com † Electronic supplementary information (ESI) available: (Fig. S1) SEM and TEM images, and (Fig. S2) mapping images of hybrid nanostructures; The CV curves and GCD curves of PPy and ZnCo 2 O 4 (Fig. S3); GCD curves of the PPy, ZnCo 2 O 4 , and ZnCo 2 O 4 /PPy (Fig. S4); The data of Specific capacitance (Table S1); The CV curves and GCD curves of PPy and ZnCo 2 O 4 in a two electrode system (Fig. S5).