Tailoring Electronic Structure and Size of Ultrastable Metalated Metal–Organic Frameworks with Enhanced Electroconductivity for High‐Performance Supercapacitors

Abstract

Abstract Utilization of metal–organic frameworks (MOFs) as electrodes for energy storage/conversion is challenging because of the low chemical stability and poor electrical conductivity of MOFs in electrolytes. A nanoscale MOF, Co 0.24 Ni 0.76 ‐bpa‐200 , possessing ultrahigh stability with uncommon semiconductor behavior ( σ =4.2×10 −3 S m −1 ) was fabricated. The MOF comprises a robust hydrophobic paddlewheel and an optimized Co/Ni ratio, with consequent control over MOF size and the degree of conjugation of the coligand. A DFT study revealed that appropriate Ni 2+ doping reduces the activation energy of the system, thus providing a higher carrier concentration, and the strongly delocalized N‐donor ligand notably increases the metal–ligand orbital overlap to achieve efficient charge migration, leading to continuous through‐bond (‐CoNi‐N‐CoNi‐) ∞ conduction paths. These structural features endow the MOF with a good cycling stability of 86.5 % (10 000 cycles) and a high specific capacitance of 1927.14 F g −1 among pristine MOF‐based electrodes.