Noble Metal‐Free Heterojunction of Ultrathin Ti 3 C 2 MXene/WO 3 for Boosted Visible‐Light‐Driven Photoreactivity

Developing highly efficient, robust, and noble metal‐free photocatalytic systems is essential for the large‐scale implementation of solar‐to‐chemical energy conversion. Herein, a novel sandwich‐like hierarchical heterostructure of Ti 3 C 2 MXene/WO 3 is created by in situ growth of ultrathin WO 3 nanosheets onto the surface of few‐layer Ti 3 C 2 nanosheets via a one‐pot solvothermal synthesis strategy. The resultant Ti 3 C 2 /WO 3 heterostructure holds a large interface contact area, an intimate electronic interaction, and a short carrier migration distance, which is beneficial for bulk‐to‐surface and interfacial charge transfer. Meanwhile, the excellent electrical conductivity of Ti 3 C 2 and the Schottky junction at the interface of WO 3 and Ti 3 C 2 expedites the spatial charge separation and transportation. As expected, the as‐prepared Ti 3 C 2 /WO 3 nanohybrids exhibit a superior visible‐light‐driven photoactivity and stability toward tetracycline hydrochloride (TC) decomposition. Across a range of Ti 3 C 2 concentrations, 3 wt% Ti 3 C 2 /WO 3 achieves the greatest photodegradation rate of 16.08 × 10 −3 min −1 that is approximately ninefold larger than that of pristine WO 3 . In addition to the underlying photocatalytic mechanism, three TC degradation pathways are identified, highlighting the important roles of ·O 2 − and h + . This study shows the potential of earth‐abundant MXene family materials in the fabrication of high‐performance and low‐cost photocatalysts applicable for environment purification.