C Fibers@WSe 2 Nanoplates Core-Shell Composite: Highly Efficient Solar-Driven Photocatalyst.

Recently, WSe2 as a typical transition metal dichalcogenide compound has attracted extensive attention due to its potential applications in electronic and optoelectronic devices. However, WSe2 alone cannot be directly used as a photocatalyst due to its inferior performance possibly caused by the strong recombination of photogenerated electron-hole pairs. Here a novel C fibers@WSe2 nanoplates core-shell composite (NPCSC) was successfully synthesized via facile, one-step thermal evaporation, in which numerous WSe2 thin nanoplates were in situ, densely and even vertically grown on the surface of the C fibers. Such composite presents highly solar-driven photocatalytic activity and stability for the degradation of various organic aqueous dyes including methylene blue and rhodamine B, and highly harmful gases like toluene, showing the great potential for environmental remediation by degrading toxic industrial chemicals using sunlight. Under simulated sunlight irradiation, comparing with commercially available WSe2 powder, the as-synthesized C fibers@WSe2 NPCSC presents significantly enhanced reaction rate constants by a factor of approximately 15, 9, and 3 for the degradation of aqueous methylene blue, aqueous rhodamine B, and gaseous toluene, respectively, due to the effective separation of photogenerated electron-hole pairs promoted by the rapid transfer of photogenerated electrons through C fibers. Moreover, this one-step thermal evaporation is an easy-handling, environmentally friendly, and low-cost synthesis method, which is suitable for large-scale production.