A Ni/Zn bi-metallic coordination supramolecular network applied for high performance energy storage material

Abstract

Coordination supramolecular networks (CSNs) with high surface areas, tunable pore sizes, open metal sites and flexible network structures can be applied for energy storage material. In this work, a Ni based CSN was synthetized through a facile hydrothermal synthesis by using 2-Quinolinecarboxylic acid, and firstly applied for energy storage material. The capacity of this Ni based CSN was achieved 149.2Cg−1 at 0.5Ag−1. Based on the flexible features of CSNs, doping extra metal ions into CSNs would enlarge the space distance of the neighboring coordination units, this change will contribute to ions diffusion. Therefore, a new Ni/Zn bi-metallic CSN was synthesized via one-step hydrothermal synthesis, the capacity of the bi-metallic CSN increased up to 210Cg−1 at 0.5Ag−1 with a potential window of 0.4V, the retention still maintained over 90% after 2000 cycles. For practical application, a solid-state symmetric device was assembled, which had the ability to power a fan with 2.5W. This promising electrochemical property may be due to the flexible network structure of CSN and the Ni/Zn bi-metallic cooperative effect.