Noble Metal‐Free Heterojunction of Ultrathin Ti<sub>3</sub>C<sub>2</sub> MXene/WO<sub>3</sub> for Boosted Visible‐Light‐Driven Photoreactivity
Xin Pang, Shixiang Xue, Tong Zhou, Mingtao Qiao, Huaxing Li, Xue Liu, Quanlong Xu, Gang Liu, Wanying Lei
Abstract
Abstract 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.