Hydrothermal Synthesis and Symmetrical Supercapacitor Study of 1D Ln-H2PDA (Ln=La and Sm) Metal-Organic Frameworks

Rare earth based metal-organic frameworks (RE-MOFs) are gaining importance in energy storage applications. Herein, we report the synthesis of two new RE-MOFs (Ln-H(2)PDA, Ln=La and Sm) under hydrothermal conditions using pyridine-2,6-dicarboxylic acid (H(2)PDA) linker. The single-crystal analysis revealed that La-H(2)PDA MOF crystallizes into monoclinic system with P 21/c space group. Sm-H(2)PDA MOF also has the same crystal system, which is confirmed by powder X-ray diffraction pattern. These MOFs are evaluated for their charge storage behaviour using conventional 3-electrode system. Both La-H(2)PDA and Sm-H(2)PDA delivered high specific capacity of 220 C g(-1) (488 F g(-1)) and 711 C g(-1) (1580 F g(-1)) at a current density of 1 A g(-1), respectively. Furthermore, a symmetric Swagelok device (Sm-H(2)PDA parallel to Sm-H(2)PDA) has been fabricated using Sm-H(2)PDA MOF as working electrodes. The maximum energy density and power density delivered by this device are 18 Wh kg(-1) and 3744 W kg(-1).

Automated summary

Rare earth based metal-organic frameworks (RE-MOFs) are important in energy storage applications. In this study, two new RE-MOFs (Ln-H(2)PDA, Ln=La and Sm) were synthesized using pyridine-2,6-dicarboxylic acid linker. These MOFs showed high specific capacity and the symmetric Swagelok device using Sm-H(2)PDA MOF as working electrodes delivered high energy density and power density.