Abstract:
Here, a novel synthesis of Mxene/α-Fe2O3/CdS step-scheme (S-scheme) hybrid heterojunction
with cascade 2D coupling interfaces was purposefully fabricated using hydrothermal techniques.
Through in-situ irradiation XPS, or UV- Visible Spectroscopy investigations, the building of Sscheme
was discovered, which may significantly increase the photocatalytic H2 evolution reaction
(HER) rate and stability. In comparison to pure CdS nanosheets (NSs), the H2 evolution rates of
Mxene/α-Fe2O3/CdS were, respectively higher. The maximum HER activity measured in the
optimized ternary composite is 51.04 mmol g-1 h-1 at 450 nm. The ternary photocatalyst, however,
continued to show substantially higher stability. Without a doubt, the strong S-scheme interfacial
electric fields could efficiently promote spatial charge separation between CdS nanosheets and α-
Fe2O3 nanosheets, while 2D Mxene nanosheets, as H2-evolution co-catalyst, could offer more
electron transfer pathways and a significant number of active sites for photocatalytic HER. This
work is anticipated to provide some fresh ideas or inspirations for the rational design of extremely
effective S-scheme heterojunction photocatalysts for more practical applications
