A Composite Catalyst Based on Perovskites for Overall Water Splitting in Alkaline Conditions

Abstract

Electrochemical water splitting is considered a sustainable way to produce H 2 . However, it is still a challenge to develop efficient and stable electrocatalysts. Here, a bifunctional composite catalyst for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) was constructed by using a facile in situ growth route, which combines the carbonization on exsolved alloy nanoparticles and sulfurization in one continues step. This composite catalyst contains Ruddlesden-Popper-type S-adsorbed (Nd 0.6 Sr 0.4 ) 3 ((Co,Fe) 0.85 Nb 0.15 ) 2 O 7 , metal sulfides, and hollow S-doped carbon fibers. Compared to the untreated catalyst, Nd 0.6 Sr 0.4 Co 0.6 Fe 0.3 Nb 0.1 O 3-δ , the composite catalyst leads to significantly enhanced OER and HER activities as well as excellent stability (more than 400 h without inactivation) during overall water splitting. Our research offers a new route to fabricate hetero-architecture materials with S-doped hollow carbon fibers on alloy nanoparticles of perovskite oxides.