Enhanced catalytic activity of edge-exposed 1T phase WS2 grown directly on a WO3 nanohelical array for water splitting

Abstract

A hierarchical electrode consisting of edge-exposed 1T phase WS₂, grown on an array of surface-modified WO₃ nanohelixes (NHs), and its enhanced catalytic performance in the hydrogen evolution reaction (HER) are presented. The oxygen-deficient WO₃ NH surface modified by controlled annealing facilitates the formation of a rich edge-exposed WS₂ during sulfurization. In addition, metallic 1T phase WS₂ is preferentially grown on the WO₃ NHs owing to the strain induced between WS₂ and curved WO₃ NHs. Such desirable structural properties, metallic 1T phase and a rich edge-exposed morphology of the catalytic electrode directly resulted in an enhanced HER performance in water splitting.