What are the Common Methods of Nanocrystalline Synthesis?
There are several techniques used for the synthesis of nanocrystalline materials, each with its own advantages and limitations:
1. Sol-Gel Process: This involves the transition of a solution into a solid gel phase. It is widely used for producing metal oxides and is known for its simplicity and low-temperature processing.
2. Chemical Vapor Deposition (CVD): This method involves the chemical reaction of gaseous precursors on a heated substrate, forming a solid material. It is commonly used for making thin films and coatings.
3. Physical Vapor Deposition (PVD): In this technique, materials are vaporized in a vacuum and then condensed onto a substrate to form thin films. It is often used for producing hard coatings and decorative finishes.
4. Ball Milling: This mechanical process involves grinding bulk materials into nanoscale particles using high-energy ball mills. It is a cost-effective method for producing large quantities of nanocrystalline powders.
5. Hydrothermal Synthesis: This method uses high-temperature and high-pressure aqueous solutions to grow crystals. It is particularly useful for synthesizing nanocrystalline ceramics and complex oxides.
