Two-dimensional amorphous NiO as a plasmonic photocatalyst for solar H₂ evolution.

Area of Science:

• Materials Science
• Photocatalysis
• Nanotechnology

Background:

• Amorphous materials are often considered photocatalytically inactive due to self-trapping of tail states.
• Crystalline NiO is unsuitable as a sole photocatalyst for H2 evolution because of intrinsic hole doping.
• Despite limitations, NiO shows promise in electrochemistry and as a cocatalyst.

Purpose of the Study:

• To investigate the photocatalytic activity of two-dimensional amorphous NiO nanostructures for solar hydrogen evolution.
• To explore the enhancement of photocatalytic performance using surface plasmon resonance (SPR).
• To demonstrate the potential of amorphous NiO as a standalone photocatalyst.

Main Methods:

• Synthesis of two-dimensional amorphous NiO nanostructures.
• Evaluation of photocatalytic H2 evolution rates under solar irradiation.
• Incorporation of SPR antenna effect through electron doping.
• Analysis of charge carrier dynamics and SPR-mediated charge release.

Main Results:

• Amorphous NiO nanostructures function as efficient and robust photocatalysts for H2 evolution without cocatalysts.
• Electron doping and SPR introduction led to an enhanced antenna-reactor structure.
• Solar H2 evolution rate increased by a factor of 19.4 due to SPR-mediated charge release.
• Demonstrated the viability of amorphous NiO as an advanced photocatalyst.

Conclusions:

• Two-dimensional amorphous NiO is a promising material for solar hydrogen evolution.
• SPR significantly boosts the photocatalytic efficiency of amorphous NiO.
• This work opens new avenues for utilizing amorphous materials in photocatalysis.