Ti3C2 MXene modified porous NiTiO3 nanorod Schottky heterojunction towards enhanced photocatalytic dye degradation

Abstract

The charge-transfer efficiency and effective surface area are crucial factors that influence the performance of photocatalysts for environmental remediation. This work focuses on forming a Schottky heterostructure by combining a two-dimensional Ti3C2 MXene layer with one-dimensional porous NiTiO3 nanorods for photocatalytic applications. The Schottky heterojunction, derived from introducing MXene in porous NiTiO3 nanorod, could simultaneously increase the effective surface area, enhance photoinduced electron transport, and impede photoexcited electron-hole recombination. Upon exposure to sunlight, the Ti3C2-MXene-modified NiTiO3 nanorod exhibited enhanced photocatalytic performance in industrial dye degradation compared to the pristine NiTiO3 nanorod. The degradation efficiency of the most common water contaminant dye, malachite green, can reach up to 98.2% in 120 min, revealing good stability and a quantum efficiency of 1.6 × 10−4. The improved activity of the heterostructure was attributed to the Schottky junction induced by the built-in internal electric field between NiTiO3 and Ti3C2-MXene, which facilitates photogenerated charge carriers to separate into electrons and holes. This study demonstrates an efficient way to fabricate Schottky heterojunction utilizing Ti3C2 MXene cocatalyst for photocatalytic pollutant degradation.