Transition Metal Dichalcogenides [MX2] in Photocatalytic Water Splitting

Abstract

The quest for a clean, renewable and sustainable energy future has been highly sought for by the scientific community over the last four decades. Photocatalytic water splitting is a very promising technology to proffer a solution to present day environmental pollution and energy crises by generating hydrogen fuel through a “green route” without environmental pollution. Transition metal dichalcogenides (TMDCs) have outstanding properties which make them show great potential as effective co-catalysts with photocatalytic materials such as TiO2, ZnO and CdS for photocatalytic water splitting. Integration of TMDCs with a photocatalyst such as TiO2 provides novel nanohybrid composite materials with outstanding characteristics. In this review, we present the current state of research in the application of TMDCs in photocatalytic water splitting. Three main aspects which consider their properties, advances in the synthesis routes of layered TMDCs and their composites as well as their photocatalytic performances in the water splitting reaction are discussed. Finally, we raise some challenges and perspectives in their future application as materials for water-splitting photocatalysts.

Research progress of transition-metal dichalcogenides for the hydrogen evolution reaction

“…The reaction time, injection rate, temperature, metal element precursor, chalcogen element precursor and the types of the used ligands are crucial to determining the shape and size of the formed nanomaterials. 56 The aforementioned work illustrates the effect of reaction precursors. The influence of ligands on the reaction process is reported, 57 and the proof process is as follows.…”

Colloidal Synthesis of Zirconium Disulphide Nanostructures and their Stability Against Oxidation

“…Colloidal synthesis provides favourable merits, such as easy to direct and proper grip of the crystallinity, monodispersity and control over the edges of the synthesized nanocrystals of materials such as TMDCS, metal oxide etc. Many ligands that are commonly used in colloidal synthesis of TMDCs include oleylamine (OLA), 1‐hexadecylamine (HAD), oleic acid (OA), oleylalcohol (OYA), trioctylphosphineoxide (TOPO), dodecylamine (DDA), squalene, 1‐dodecanethiol (1‐DDT), stearic acid, octadecanamine (ODA) and 1‐octadecene (ODE) [12] . However, ligand obtained from organic source are also deployed in synthesis of stable nanocrystals of materials.…”

“…This method provides the advantage of ease of manipulation of reaction parameters to produce nanomaterials with various morphologies, sizes, and phases. [10,11,12] Douri et al offer pulsed laser ablation process, a new method of synthesis which is employed in aqueous solution. [10,11] It is quite different from the chemical method of synthesis where an organic liquid is used as the reaction medium.…”

“…Many ligands that are commonly used in colloidal synthesis of TMDCs include oleylamine (OLA), 1-hexadecylamine (HAD), oleic acid (OA), oleylalcohol (OYA), trioctylphosphineoxide (TOPO), dodecylamine (DDA), squalene, 1-dodecanethiol (1-DDT), stearic acid, octadecanamine (ODA) and 1octadecene (ODE). [12] However, ligand obtained from organic source are also deployed in synthesis of stable nanocrystals of materials. Anathi et al made use of an organic ligand, tannic acid extracted from leaves of green tea to stabilize metal oxide during the synthesis of iron oxide.…”

“…Colloidal method of synthesis could help in the synthesis of nanocrystals. This method provides the advantage of ease of manipulation of reaction parameters to produce nanomaterials with various morphologies, sizes, and phases [10,11,12] . Douri et al offer pulsed laser ablation process, a new method of synthesis which is employed in aqueous solution [10,11] .…”