Metal−organic framework (MOF)-derived nanostructures are portraying a major confront to the quest for highperforming electrocatalysts for energy conversion and storage devices largely because of their tunable synthesis, high surface area, and presence of various heteroatoms depending upon the choice of ligands used as precursors. In this regard, multifunctional electrode material development with high performance is a contemporary trend. We report an innovative integrated nanostructure of Co-NC3 (Co-MOF annealed at 700 °C for 3 h under Ar) bestowed with admirable potential, derived from a newly designed Co(II)-based MOF comprising benzene-1,3,5-tricarboxylic acid and 1,10-phenanthroline. The Co-NC3 nanostructure derived from Co-MOF was found to be a highly efficient catalyst for the oxygen reduction reaction with onset potential (0.90 V vs RHE) and halfwave potential (0.81 V vs RHE) comparable to those for the commercial 20 wt % Pt/C catalyst (0.91 and 0.83 V vs RHE). Next, the same catalyst was explored as a commendable energy-storage material for supercapacitors with a specific capacitance value of 310 F/ g at a 0.5 A/g current density. We fabricated a solid-state asymmetric supercapacitor device from Co-NC3 and lit light-emitting diodes of 1.8 V each using three such supercapacitors in series. For the first time, a Co-MOF-derived supercapacitor was deployed successfully in a solar photovoltaic-based sensor node system.

As the postsynthesis-processed metal−organic materialbased catalysts for energy applications add additional cost to the whole process, the importance of developing synthesized usable pristine catalysts is quite evident. The present work reports a new Cu-based coordination polymer (Cu-CP) catalyst to be used in its pristine form for oxygen reduction reaction (ORR) application. The catalyst was characterized using single-crystal X-ray diffraction, field emission scanning electron microscopy, and X-ray photoemission spectroscopy. The Cu-CP exhibits admirable electrocatalytic ORR activity with an onset potential of 0.84 V versus RHE and a half wave potential of 0.69 V versus RHE. As revealed by the density functional theory-based computational mechanistic investigation of the electrocatalytic ORR process, the electrochemically reduced Cu(I) center binds to the molecular O 2 through an exergonic process (ΔG = −6.8 kcal/mol) and generates the Cu(II)−O 2•− superoxo intermediate. Such superoxo intermediates are frequently encountered in the catalytic cycle of the Cu-containing metalloenzymes in their O 2 reduction reaction. This intermediate undergoes coupled proton and electron transfer processes to give OH − in an alkaline medium involving H 2 O 2 as the intermediate. The electrocatalytic performance of Cu-CP remained stable even up to 3000 cycles. Overall, the newly developed Cu-CP-based electrocatalyst holds promising potential for efficient biomimetic ORR reactivity, which opens new possibilities toward the development of robust coordination polymer-based electrocatalysts.

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