The Effects of Compositional Tuning on the Bifunctional Oxygen Electrocatalytic Behavior of Nickel Sulfoselenides

Nickel sulfoselenides (NiSSe) are a family of electrocatalystswith promise for application to the oxygen evolution reaction (OER),oxygen reduction reaction (ORR), and therefore bifunctional oxygenelectrocatalysis (BOE). Tuning the S/Se composition of a series ofNi(3)S(2-x )Se( x ) NiSSe influences electrocatalytic performance, witha near unity S/Se ratio optimal for OER and Se-rich compositions optimalfor ORR and BOE applications. Using chemical and physical characterization,we show that Se addition results in a greater oxidative stabilityand electrocatalytic performance. Finally, we demonstrate NiSSe electrocatalystsas BOEs in Zn-air batteries and find that they are more stablethan commercial Pt/C electrocatalysts.

Automated summary

Nickel sulfoselenides (NiSSe) are promising electrocatalysts for oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and bifunctional oxygen electrocatalysis (BOE). Tuning the S/Se composition of Ni(3)S(2-x )Se( x ) NiSSe influences electrocatalytic performance, with a near unity S/Se ratio optimal for OER and Se-rich compositions optimal for ORR and BOE applications. By adding Se, the oxidative stability and electrocatalytic performance of NiSSe are improved. NiSSe electrocatalysts are more stable than commercial Pt/C electrocatalysts in Zn-air batteries.