Pillared nickel-based metal-organic frameworks as electrode material with high electrochemical performance

Abstract

A pillared nickel-based MOFs, Ni 2 (bdc) 2 P (bdc is the 1,4-benzenedicarboxylic acid and P is dabco(1,4-diazabicyclo[2.2.2]-octane)), and Zn-doped pillared (Zn/Ni) 2 (bdc) 2 P are synthesized and their electrochemical properties as an electrode material are firstly evaluated. The Ni 2 (bdc) 2 P electrode material has a specific capacity of 177.6C g −1 and 48C g −1 at 0.5 A g −1 and 10 A g −1 , respectively. Much higher specific capacities of 298.5C g −1 at 0.5 A g −1 and 104 C g −1 at 10 A g −1 are obtained for the (Zn/Ni) 2 (bdc) 2 P, indicating good rate capability. In addition, the pillared (Zn/Ni) 2 (bdc) 2 P also possesses more stable cycling performance than the pillared Ni 2 (bdc) 2 P. The excellent electrochemical performance of both Ni 2 (bdc) 2 P and (Zn/Ni) 2 (bdc) 2 P can be attributed to their 3D framework structure with open channels and large surface area, hierarchical porous structure and high electrical conductivity. An asymmetric supercapacitor (ASC) (Zn/Ni) 2 (bdc) 2 P//AC is assembled to evaluate the practical application of (Zn/Ni) 2 (bdc) 2 P electrode. The assembled ASC possesses a high energy density of 12.2 W h kg −1 at a power density of 371.5 W kg −1 and excellent cycling performance. Furthermore, two assembled ASCs in series are used to light up a red and a yellow light-emitting diode (LED). Nickel-based pillared metal-organic frameworks as electrode materials with excellent electrochemical performance and have promising potential applications in energy storage. • Pillared Ni 2 (bdc) 2 P and (Zn/Ni) 2 (bdc) 2 P were synthesized. • The specific capacities of Ni 2 (bdc) 2 P and (Zn/Ni) 2 (bdc) 2 P are 177.6 and 298.5 C g −1 at 0.5 A g −1 , respectively. • (Zn/Ni) 2 (bdc) 2 P//AC has an energy density of 12.2 W h kg −1 and a high power density of 6141.6 W kg −1 .