Diamond with Unexpected Multi-Scale Pores

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Diamond products encompass various forms like nano-polycrystalline diamond (NPD) and micron-polycrystalline diamond (MPD).
• Porous diamond stands out due to its high surface area-to-volume ratio (SA/V) and surface functionality.
• Existing synthesis methods like etching or microwave plasma chemical vapor deposition (MPCVD) have limitations.

Purpose of the Study:

• To develop an efficient, inexpensive method for synthesizing millimeter-level porous diamond.
• To explore an alternative to etching or MPCVD techniques for porous diamond production.
• To characterize the multiscale pore structure of the synthesized porous diamond.

Main Methods:

• Proposal of a high-temperature and high-pressure method based on a soluble skeleton (HPHT-ss).
• Synthesis of millimeter-level porous diamonds using the developed HPHT-ss technique.
• Analysis of temperature-pressure conditions and the formation mechanism of porous diamonds.

Main Results:

• Successful synthesis of millimeter-level porous diamonds via the HPHT-ss method.
• The synthesized porous diamond exhibits multiscale pores: macropores (average 75 µm) and mesopores (average 19 nm).
• This multiscale pore distribution is a unique feature compared to porous diamond produced by other methods.

Conclusions:

• The HPHT-ss method provides an efficient and cost-effective route for porous diamond synthesis.
• Porous diamond synthesized via HPHT-ss possesses a unique multiscale pore structure.
• This material holds potential for applications in catalysis, adsorption, and electrochemistry due to its properties.