MXene-Based Nanocomposites for Enhanced Photocatalytic Hydrogen Production via Water Splitting

Abstract

The growing energy demand across the world and threatening climate changes have brought pressure to the need to adopt clean and renewable sources of energy, and hydrogen has become an alternative source of energy. Splitting of water by photocatalysis is one of the most promising green and sustainable methods of production of hydrogen, and its viability is hampered by high charge recombination rates and the poor absorption of visible light by traditional photocatalysts. Recently, a new type of transition metal carbides and nitrides that are two-dimensional called MXenes has been discovery known due to its high electrical conductivity, surface chemistry that can be altered with potential to transfer charge. The objective of this work was to review and analyze the MXene-based nanocomposites combined with semiconductors to enhance photocatalytic hydrogen evolution using visible light. Ti₃C 2 T X Mxene was synthesized by using HF etching of Ti 3 AlC 2 and was mixed with g-C 3 N 4 and CdS by using hydrothermal processes. XRD, SEM, TEM, UV-Vis DRS, PL spectroscopy and XPS were applied in characterizing the composites. Gas chromatograph was utilized in the determination of hydrogen production in the presence of visible light. The findings indicated that the rate of hydrogen evolution of MXene/g-C 3 N 4 and MXene/CdS nanocomposites is much more remarkable compared to the rates of their counterparts, i.e., 3120 and 2850 0-mol/g-h-1 critically (more than 3-times elevated). The improvement was ascribed to more effective absorption of light, separation of the charges, and stability after repeated cycles. In conclusion, the MXene-based nanocomposites offer the possibility of enhancement of photocatalytic production of solar fuels, leading to the next phase of solar fuel development.

Keywords: MXene, Photocatalysis, Hydrogen Evolution, Water Splitting, g-C₃N₄, CdS, Nanocomposites, Visible Light