Boosting the photocatalytic activity of CdLa2S4 for hydrogen production using Ti3C2 MXene as a co-catalyst

Abstract Exploring efficient, stable and low-cost photocatalysts for photocatalytic hydrogen production remains a challenge in the field of energy conversion. Here, two-dimensional Ti3C2 nanosheets were fabricated via etching Ti3AlC2 with HF, followed by ultrasonic exfoliation. Then CdLa2S4/Ti3C2 nanocomposites were fabricated by growing CdLa2S4 nanoparticles in situ on the surface of these Ti3C2 nanosheets. The resultant CdLa2S4/Ti3C2 nanocomposites exhibited an excellent photocatalytic activity for H2 production from water splitting under visible light illumination. When the content of Ti3C2 was 1.0 wt%, the CdLa2S4/Ti3C2 nanocomposites presented maximum hydrogen production rate of 11182.4 μmol·g−1·h−1, which was 13.4 times as high as that of pristine CdLa2S4 and even outperformed Pt-loaded CdLa2S4. The apparent quantum efficiency reached 15.6% at 420 nm. In addition, the CdLa2S4/Ti3C2 photocatalyst still maintained high photocatalytic activity after six cycles. The exceptional performance of CdLa2S4/Ti3C2 originated from the superior electrical conductivity of Ti3C2 MXene, which facilitated the separation of photo-generated electron-hole pairs. This work presents the potential of earth-abundant MXene materials in the construction of high efficiency and low-cost photocatalysts toward solar energy conversion.