ZnO@Ti3C2 MXene interfacial Schottky junction for boosting spatial charge separation in photocatalytic degradation

•The ZnO@Ti3C2 MXene composite is obtained via a simple hydrothermal method for promoting the photocatalytic degradation.•The ZnO@Ti3C2 MXene composite presents the excellent photocatalytic degradation performance (94.84%).•The addition of Ti3C2 MXene forms a Schottky junction between ZnO and Ti3C2 MXene.•The Schottky junction prevents the photogenerated electrons returning to ZnO, and promotes the separation of carriers. Herein, we report a ZnO@Ti3C2 MXene composite obtained using a simple hydrothermal method for increasing the photocatalytic degradation ability of methylene blue (MB). When the addition amount of Ti3C2 MXene is 50%, the ZnO@Ti3C2 MXene composite exhibited the best photocatalytic degradation performance (94.84%), and the reaction rate constant is 0.01223 min−1, which is 47 and 30 times of pure ZnO (5.59%, 0.026 ×10–2 min−1) and pure Ti3C2 MXene (7.56%, 0.04050 ×10–2 min−1), respectively. Moreover, the ZnO@Ti3C2 MXene composite exhibited good stability. The photocatalytic mechanism of ZnO@Ti3C2 MXene composite is proposed. The addition of Ti3C2 MXene forms a Schottky junction between ZnO and Ti3C2 MXene. The Schottky junction prevents the photogenerated electrons from returning to ZnO and promotes the separation of photogenerated electrons and holes, thus effectively improving the photocatalytic performance of ZnO@Ti3C2 MXene composite.