A polythreaded MnII-MOF and its super-performances for dye adsorption and supercapacitors†
A new polythreaded MnII-MOF based on a tridentate N-containing ligand was synthesized via a hydrothermal method, namely, [Mn2(Tipa)2(1,4-bdc)2(H2O)2]·3H2O (MnTB), where Tipa and 1,4-bdc are short for tri(4-imidazolylphenyl)amine and 1,4-benzenedicarboxylate. MnTB possesses a fascinating 2D → 2D polyrotaxane layer with a (42·6)(42·63·8) topology, and these layers are extended into a 3D polythreaded framework with a polythreaded character. The crystal was pulverized and directly used as both a dye adsorbent and supercapacitor. In the adsorption test, MnTB showed great adsorption ability for methyl orange (MO), where the maximum adsorption capacity was about 1500 mg g−1. When tested as a supercapacitor, MnTB exhibited a high capacitance of 1357.8 F g−1 at 1 A g−1 in 6 M KOH solution and achieved no attenuation after 2000 cycles. The asymmetric supercapacitor device (MnTB//AC) achieved 114.6 F g−1 at 1 A g−1 and a maximum energy density of 35.8 W h−1 kg−1 at a power density of 750 W kg−1 with a voltage window of 1.5 V.