A vertical-oriented WS2 nanosheet sensitized by graphene: an advanced electrocatalyst for hydrogen evolution reaction

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Electrocatalytic hydrogen production is crucial for sustainable energy.
• Layered transition metal dichalcogenides (LTMDs), like WS2, show promise for hydrogen evolution reaction (HER).
• Existing horizontally laid nanosheets have limited active edge sites.

Purpose of the Study:

• To synthesize vertical-oriented WS2 nanosheets.
• To decorate WS2 nanosheets with reduced graphene oxide (rGO) for improved HER.
• To investigate the synergistic effects of rGO and WS2 for electrocatalysis.

Main Methods:

• Hydrothermal synthesis of WS2 nanosheets.
• Facile sulfurization process to create vertical orientation.
• Decoration of WS2 nanosheets with ultrathin rGO nanoplates.

Main Results:

• Successfully synthesized vertical-oriented WS2 nanosheets.
• Achieved novel decoration of rGO on vertical WS2 nanosheets, enhancing electron transport.
• The rGO/WS2 nanosheets demonstrated improved HER activity, requiring only 229 mV overpotential for 10 mA cm(-2) current density.

Conclusions:

• Vertical-oriented WS2 nanosheets decorated with rGO exhibit superior HER performance.
• The hybrid rGO/WS2 structure shows significant synergistic effects.
• This approach presents a viable strategy for efficient electrocatalytic hydrogen production.