Cluster-Based Multifunctional Copper(II) Organic Framework as a Photocatalyst in the Degradation of Organic Dye and as an Electrocatalyst for Overall Water Splitting

Abstract

On the basis of the unprecedented one-dimensional {Cu2(tetrazole)(SO4)(OH)}n cluster, a novel two-dimensional layered copper(II) organic framework, {[Cu2(TTB)(SO4)(OH)]·H2O·MeCN}n (1), is constructed from 1-(tetrazo-5-yl)-4-(triazo-1-yl) benzene (HTTB) and CuSO4 under hydrothermal conditions. Photocatalytic experiments revealed that 1 is an outstanding semiconducting material (Eg = 2.21 eV) for the degradation of methyl blue under UV light irradiation. Besides, electrocatalytic research showed that the 1@NF electrode shows better oxygen evolution reaction (OER) performance than RuO2@NF, reaching a current density of 10 mA·cm–2 when the overpotential of OER is 377 mV in 1.0 M KOH electrolyte and the Tafel slope of 1@NF is 15.6 mV·dec–1. Meanwhile, the overpotential of the hydrogen evolution reaction (HER) is 242 mV at a current density of 10 mA·cm–2, with the Tafel slope being 23.1 mV·dec–1, also suggesting the HER performance of 1@NF is better than that of Pt/C@NF. The durability test showed the electrocatalytic activity of 1@NF was maintained at 90% after 12 h. Photocatalytic and electrocatalytic properties show that 1 is an excellent candidate as a multifunctional material to solve environmental pollution and energy shortages.