Facile preparation of semimetallic WP2 as a novel photocatalyst with high photoactivity

摘要

Searching for inexpensive and earth-abundant photocatalysts with high activities has attracted considerable research in recent years. In this work, semimetallic tungsten diphosphide (WP _(2) ) micro-particles are explored as a novel photocatalyst for the first time. The WP _(2) particles were synthesized through a solid-state reaction route via vacuum encapsulation technique following by water washing. The first principle calculations and electric transport measurements show a semimetallic characteristic of WP _(2) , however a strong absorption in the UV range is observed. The prepared WP _(2) particles exhibit an admirable photocatalytic activity towards oxidation of methyl orange and reduction of water for H _(2) evolution with the assistance of co-catalyst element Pt under UV light irradiation. Hydroxyl radicals detected by fluorescence spectroscopy in the solution in the presence of WP _(2) under UV light irradiation confirms the photoactivity. Furthermore, the photocatalyst shows a good photostability and reusability even after three successive experiment runs. Based on the experimental measurements and theoretical calculations, a possible photocatalytic mechanism is proposed for semimetallic WP _(2) . The present study may provide a chance for practical applications of the semimetallic material WP _(2) in the field of photocatalysis.