Two-dimensional materials and composites as potential water splitting photocatalysts: A review

Hydrogen production via water dissociation under exposure to sunlight has emanated as an environmentally friendly, highly productive and expedient process to overcome the energy production and consumption gap, while evading the challenges of fossil fuel depletion and ecological contamination. Various classes of materials are being explored as viable photocatalysts to achieve this purpose, among which, the two-dimensional materials have emerged as prominent candidates, having the intrinsic advantages of visible light sensitivity; structural and chemical tuneability; extensively exposed surface area; and flexibility to form composites and heterostructures. In an abridged manner, the common types of 2D photocatalysts, their position as potential contenders in photocatalytic processes, their derivatives and their modifications are described herein, as it all applies to achieving the coveted chemical and physical properties by fine-tuning the synthesis techniques, precursor ingredients and nano-structural alterations.