Lewis acid molten salts prepared Ti3C2Cl2 MXenes assembling with g-C3N4 nanosheets for enhanced photocatalytic H2 evolution

Photocatalytic hydrogen (H 2 ) evolution is expected to be a promising approach to generating a clean energy source (H 2 ) with low carbon emissions, which is vital to solving environmental degradation and energy shortages. The critical challenge to designing highly efficient photocatalysts is the fast recombination of photo-generated carriers; thus, we select Ti 3 C 2 Cl 2 MXene with excellent metal characteristics to serve as a co-catalyst and combine with g-C 3 N 4 . The Ti 3 C 2 Cl 2 /g-C 3 N 4 composites exhibit an enhanced photocatalytic hydrogen evolution activity (maximum 155.9 μmol h −1 ) while they hardly perform photocatalytic activities. The photoluminescence (PL) spectra shows that Ti 3 C 2 Cl 2 MXenes help boost the separation of photo-generated carriers of g-C 3 N 4 and finally strengthen the photocatalytic hydrogen evolution performance. The ultraviolet–visible (UV–vis) spectra illustrate that composites perform a strengthened light absorption, which fits well with the results in the hydrogen evolution experiment. Thus, we fabricated a highly efficient photocatalyst through a safer molten salt approach without hydrofluoric acid (HF). We believe this work will offer a safer approach to manufacturing catalysts decorated with MXenes for highly efficient photocatalytic H 2 evolution.