One-pot synthesis of Ru/Nb2O5@Nb2C ternary photocatalysts for water splitting by harnessing hydrothermal redox reactions

MXenes, 2D transition metal carbides/nitrides, have been demonstrated as promising platform for fabricating novel composites with interesting photo-/electrochemical properties. It is desirable to gain insights into the reactivity of MXenes, enabling the controllable transformation of MXenes. Here, a one-pot hydrothermal synthesis method of MXene-based photocatalyst is validated by harnessing the reducibility of Nb2CTx MXene. The origin of reducibility of Nb2CTx during the hydrothermal oxidation process was demonstrated as the active hydrogen produced from the water splitting in the presence of Nb2CTx, which reduced Ru3+ in situ to Ru nanoparticles on Nb2O5 nanowires derived from Nb2CTx. Compared with the traditional photo-deposition method, the chemical valance of the noble metal Ru/Pt obtained by the one-pot synthesis method was closer to the metal state, which reduced the charge transfer resistance by 82.5%. It led to the photocatalytic hydrogen production of 10.11 mmol·h−1·g−1 with 41.25% apparent quantum yield at 313 nm.