CuNi–PTC metal–organic framework: unveiling pseudocapacitive energy storage and water splitting capabilities

Abstract

Metal–organic frameworks (MOFs), owing to their distinctive structural properties and customizable functionalities, have been garnering significant attention in the pursuit of advanced energy storage and conversion technologies. In this work, a bimetallic MOF, CuNi–PTC, has been synthesized through a straightforward method. Investigations reveal its potential as a high-performance electrode material for supercapacitors and as an electrocatalyst for water splitting. The CuNi–PTC MOF features a large specific surface area, hierarchical porosity, and strong structural stability, as evidenced by spectroscopic and electron microscopy analyses. As a supercapacitor electrode material, CuNi–PTC delivers an impressive specific capacitance of 1066.24 F g⁻¹ at a current density of 1 A g⁻¹, along with excellent cycling stability, retaining 94% of its capacity after 5000 charge–discharge cycles. Additionally, the electrocatalytic performance of CuNi–PTC for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) was assessed, showing overpotentials of 212 mV for the HER and 380 mV for the OER at a current density of 10 mA cm⁻², along with exceptional long-term durability.