The Effects of Compositional Tuning on the Bifunctional Oxygen Electrocatalytic Behavior of Nickel Sulfoselenides
Bryan R. Wygant, Brian Washington, Ciara Wright, Gabriel A. Goenaga, Thomas A. Zawodzinski, Timothy N. Lambert
Abstract
Nickel sulfoselenides (NiSSe) are a family of electrocatalysts with promise for application to the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and therefore bifunctional oxygen electrocatalysis (BOE). Tuning the S/Se composition of a series 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. Using chemical and physical characterization, we show that Se addition results in a greater oxidative stability and electrocatalytic performance. Finally, we demonstrate NiSSe electrocatalysts as BOEs in Zn–air batteries and find that they are more stable than commercial Pt/C electrocatalysts.