Layered CuI-MOFs containing [Mo8O26]4− clusters as supercapacitor electrode materials

Crystal structure of poly[bis(μ2-1,4-di(1H-imidazol-1-yl)benzene-κ2 N:N′)-(μ2-tetraoxidomolybdato(VI)-κ2 O:O′)cobalt(II)], C24H20N8O4MoCo

“…The lengths of the Co-O (2.0147(12) Å) and Co-N (2.1755 (14) and 2.1884(14) Å) bonds are comparable to those observed in the related literature [16][17][18]. The bib ligand acts as a bidentate ligand, each Co(II) ion is surrounded by four bib ligands, which extend into a 2D layer.…”

“…, and so on [9]. Currently, polyoxomolybdate-based metal-organic complexes (MOCs) have attracted attention, not only due to their diverse structures caused by different amounts of molybdenum centers [10], but also for their wide range of applications in the fields of fluorescent sensing [11], catalysis [12], magnetism [13], electrode materials [14] and nanotechnology [15]. Here, we report on an experiment to introduce the 1,4-di (1H-imidazol-1-yl)benzene (bib) ligand into the reaction system containing [MoO4] 2anions to synthesize a POM-based cobalt(II) complex.…”

Supercapacitor electrodes based on metal‐organic compounds from the first transition metal series

“…So far, reported copper‐organic compounds and their composites with SC properties can be divided into copper carboxylate MOFs ( 140 ‐ 157 ), copper polyoxometalate organic frameworks (Cu‐POMOFs, 158 ‐ 176 ), copper polyamine or polyphenol MOFs ( 177 ‐ 183 ), copper porphyrin compounds ( 184 ‐ 188 ), etc. Copper can exhibit electrochemical activity through the redox reaction between Cu(0), Cu(I), and Cu(II), and its organic compounds have been widely studied in SCs 73,77,78,80,116,159‐183 . Relevant conversion process can be expressed by the following equations 164,167,174 : …”

“…Another important type of copper‐organic compounds is the POMOFs that has attracted recent research interests in the field of SC ( 158 ‐ 176 ) 28,38,77,169‐174 . POMOFs have many exceptional advantages for SC applications, such as long cycling life due to their poor solubility in water and in common inorganic and/or organic solvents, and crystalline forms which are suitable for investigating their effect on SC properties.…”

“…Similar phenomenon was also found in Chai's other work ( 167 and 168 ), 172 and these results indicate that the fully oxidized Keggin POMs can provide a higher oxidation capacity. Wang and coworkers constructed two layered Cu(I)‐based POMOFs ( 171 and 172 ) with β‐[Mo 8 O 26 ] 4− polyoxoanions and flexible bnie (Figure 4A) linker 174 . Both SC electrodes fabricated with 171 and 172 showed a poor cycling stability with nearly half of the capacitance loss after 5000 cycles.…”