Nanoporous gold prism microassembly through a self-organizing route.

Area of Science:

• Materials Science
• Nanotechnology
• Surface Chemistry

Background:

• Nanoporous gold (NPG) is a versatile material with applications in catalysis and sensing.
• Controlling the morphology and surface properties of NPG is crucial for optimizing its performance.
• Existing methods for NPG modification can be complex or alter desired structural features.

Purpose of the Study:

• To report a simple and spontaneous synthesis method for nanoporous gold prism microassemblies.
• To investigate the effect of concentrated hydrochloric acid treatment on NPG morphology and structure.
• To compare the resulting NPG structures with those obtained through annealing.

Main Methods:

• Immersion of nanoporous gold into concentrated hydrochloric acid.
• Characterization of the resulting microassembly's ligament size and crystal face orientation.
• Comparative analysis with NPG samples subjected to thermal annealing.

Main Results:

• Achieved synthesis of NPG prism microassemblies with highly dense skins.
• Observed coarsening of ligament size to several hundred nanometers.
• Preserved crystal face orientation despite coarsening.
• Observed significantly different morphology compared to annealed NPG.

Conclusions:

• Concentrated hydrochloric acid provides a facile route to modify NPG morphology.
• This method yields NPG microassemblies with distinct structural characteristics compared to annealing.
• The preserved crystal orientation suggests potential for tailored NPG applications.