Ti3C2 MXene nanoparticles modified metal oxide composites for enhanced photoelectrochemical water splitting

Abstract MXene, an emerging family of two-dimensional (2-D) material, has shown outstanding electronic properties and promise for the applications on energy storage and conversion. In this paper, Ti3C2 MXene nanoparticles were synthesized by a facile solvent exfoliation method and used to construct metal oxide/Ti3C2 heterostructures. When these heterostructures were used as photoanodes for photoelectrochemical water splitting, significantly improved photoactivity and stability were achieved. Compared to pristine TiO2, 6-fold enhanced applied bias photon-to-current efficiency (ABPE) was achieved for TiO2/Ti3C2 heterostructures. According to the electron spin resonance, electrical impedance spectroscopic and Mott-Schottky measurements, the enhanced photoelectrochemical performance was ascribed to the presence of Ti3C2 as oxygen evolution cocatalysts and the strong interfacial interactions between metal oxide and Ti3C2. Therefore, our research provides a new way to design MXene-based heterostructures for solar energy conversion applications.