On the Synthesis of Morphology‐Controlled Transition Metal Dichalcogenides via Chemical Vapor Deposition for Electrochemical Hydrogen Generation

• Published in: Physica status solidi. PSS-RRL. Rapid research letters 2019-12, Vol.13 (12), p.n/a
• Main Authors: Sharma, Rahul, Sahoo, Krishna Rani, Rastogi, Pankaj Kumar, Biroju, Ravi K., Theis, Wolfgang, Narayanan, Tharangattu N.
• Format: Article
• Language: English
• Subjects: atomically thin alloys; Catalytic activity; Chalcogenides; Chemical synthesis; Chemical vapor deposition; Dendritic structure; dendritic structures; hydrogen evolution; Hydrogen evolution reactions; Hydrogen production; Molybdenum disulfide; Morphology; Organic chemistry; Photoelectrons; Photoluminescence; Ternary alloys; Transition metal compounds; transition metal dichalcogenides
• ISSN: 1862-6254; 1862-6270
• DOI: 10.1002/pssr.201900257

Shape‐engineered atomically thin transition metal dichalcogenide (TMD) crystals are highly intriguing systems with regard to both fundamental and applied science. Herein, a chemical vapor deposition‐assisted generalized synthesis strategy for the triangular‐ and dendritic‐shaped TMDs and their ternary alloys is proposed, and the TMD structures' potential for electrocatalytic hydrogen evolution reaction (HER) applications is demonstrated. The alloy formation is confirmed via micro‐Raman and photoluminescence studies and further verified using transmission electron microscopy and X‐ray photoelectron spectroscopy. The HER activities of MoS2 and MoSe2 triangles are compared with those of their dendritic structures, and an enormous improvement in terms of overpotential and current density is observed for the dendritic structures. A further enhancement of the HER activity is observed in MoS2(1−x)Se2x triangular and dendritic structures, with dendritic MoS2(1−x)Se2x providing the best activity. The demonstrated nonequilibrium growth technique opens new avenues for the synthesis of morphology‐controlled, large area, complex, and atomically thin TMD structures, which can have unprecedented properties, such as the enormous catalytic activity, tunable luminescence, etc., as presented in this article. A generalized chemical vapor deposition (CVD)‐based synthesis strategy for morphology‐controlled transition metal dichalcogenides (TMDs) and their alloys, and the enhanced hydrogen evolution activities of dendritic TMD alloys: Optical images of dendritic 2H‐MoS2(1−x)Se2x structures are shown in the figure with their photoluminescence properties indicated by the red color. Augmented electrocatalytic hydrogen generation is also shown in the schematic.