CuCo2S4 hollow nanoneedle arrays supported on Ni foam as efficient trifunctional electrocatalysts for overall water splitting and Al–Air batteries.

Design and synthesis of multi-functional electrocatalysts with high efficiency and low cost to replace noble metals are significantly important to realize new energy technologies. Herein, we report CuCo 2 S 4 hollow nanoneedle arrays as efficient trifunctional electrocatalysts for overall water splitting and aluminium-air batteries. CuCo 2 S 4 hollow nanoneedle arrays are grown on Ni foam (NF) via a facile hydrothermal method. Benefiting from the porous and hollow structure to expose more active sites, the CuCo 2 S 4 /NF hollow nanoneedle arrays exhibit superior electrocatalytic performance for hydrogen evolution (HER), oxygen evolution (OER), oxygen reduction reactions (ORR) in alkaline electrolytes. The corresponding experimental HER and OER overpotentials of CuCo 2 S 4 /NF catalyst are 61 mV and 189 mV at 10 mA cm−2 in 1.0 M KOH. In an assembled primary Al-air battery, the CuCo 2 S 4 /NF catalysts demonstrate an outstanding peak power density of 160 mW cm−2. This work provides a new strategy for developing non-noble metal multiple-functional catalysts for energy conversion and energy storage devices. Image 1 • Hollow nanoarrays copper-cobalt intermetallic sulfide on Ni foam are synthesized. • CuCo 2 S 4 exhibit synergistic electrocatalytic activity for HER, OER and ORR. • Al-air batteries self power the two-electrode configuration during water splitting. [ABSTRACT FROM AUTHOR]