Active Sites-Enriched Hierarchical Weyl Semimetal WTe Nanowire Arrays for Highly Efficient Hydrogen Evolution Reaction.

Weyl semimetal tungsten ditelluride (WTe), characterized by its high conductivity and robust topological surface state, possesses promising catalytic properties for electrochemical reactions. However, the synthesis of well-defined WTe nanostructures has faced challenges, hindering their practical applications. This study introduces a new method for synthesizing Weyl semimetal WTe nanowire arrays grown vertically on conductive carbon cloth. Through a selective synthesis process, WTe and core-shell semiconductor-semimetal WO -WTe nanowires are successfully fabricated via tellurization of WO nanowires. To gain a comprehensive understanding of the structural, chemical, and catalytic properties of these nanowires, WO nanowires are gradually converted to WO -WTe and WTe nanowires. The hierarchical structure of the WTe nanowires greatly increases the number of active sites and promotes efficient charge transfer, resulting in exceptional electrochemical catalytic performance. In the hydrogen evolution reaction, WTe nanowire arrays exhibit an exceptionally low Tafel slope of 49 mV dec, as well as remarkable stability under both high and low current densities. These exceptional properties highlight the potential of WTe nanowire arrays as highly effective electrochemical catalysts. It is expected that this facile synthesis approach will pave the way for the fabrication of well-structured Weyl semimetal nanowires, enabling further exploration of their intriguing properties and promising applications.