Anchoring 0D Cd0.5Zn0.5S nanoparticles on a 3D porous N-doped Ti3C2Tx MXene matrix for efficient photocatalytic hydrogen evolution

The accessibility of photogenerated charge transfer channels and the activity of catalytic reaction sites are critical for efficient hydrogen evolution reaction (HER). Herein, a 3D porous N-doped Ti3C2Tx MXene matrix confining Cd0.5Zn0.5S nanoparticles (N-TCT@CZS) was fabricated via electrostatic absorption, thermal nitridation, and in situ growth processes, forming a stable heterojunction with excellent photocatalytic HER activity. Comprehensive experimental and theoretical analyses indicated that N dopants could induce more unsaturated structures and increase the abundance of active sites, while the 3D N-TCT MXene matrix with a stable scaffold configuration and interconnected porous channels could promote charge transfer kinetics, which synergistically realizes electronic structure modulation and spatial configuration design of photocatalysts. Besides, the Cd-N bonds between the N-TCT MXene and CZS enhance the interfacial interaction and expedite the directional interfacial charge transfer, thus substantially boosting photocatalytic hydrogen evolution. Consequently, the optimal N-TCT@CZS-3 nanohybrid photocatalyst possesses a superior photocatalytic HER rate of 10.90 mmol g(-1) h(-1), which is 4.8 times higher than that of the pristine CZS nanoparticles. This work proposes an applicable avenue for designing and fabricating novel functional 3D MXene-supported semiconductor materials for solar energy conversion.

Automated summary

The efficient hydrogen evolution reaction (HER) relies on the accessibility of photogenerated charge transfer channels and the activity of catalytic reaction sites. In this study, a 3D porous N-doped Ti3C2Tx MXene matrix was used to confine Cd0.5Zn0.5S nanoparticles (N-TCT@CZS), forming a stable heterojunction with excellent photocatalytic HER activity. The N dopants induced unsaturated structures and increased active sites, while the 3D N-TCT MXene matrix promoted charge transfer kinetics. The Cd-N bonds between N-TCT MXene and CZS enhanced interfacial interaction and expedited interfacial charge transfer, significantly boosting photocatalytic hydrogen evolution.