Nano silver powder refers to metallic silver elemental powder with a particle size ranging from 1-100 nanometers (nm), also commonly known as nano silver or silver nanoparticles. Due to its unique physical and chemical properties, it plays a key role in multiple cutting-edge fields such as electronics, medicine, catalysis, and more. The particle size distribution range of nano silver powder is narrow, with commonly used particle sizes of 20nm, 50nm, 80nm, and 100nm. The purity of nano silver powder can reach 99.99%. We can also supply nano silver powder and aqueous dispersion.
The excellent performance of nano silver powder mainly comes from its nanoscale size, which is manifested in the following aspects:
1. High specific surface area and surface activity
Nanoscale particles imply a large specific surface area and a high proportion of surface atoms, making them highly chemically active. This characteristic is the basis for its excellent catalytic and antibacterial properties.
2. Excellent conductivity and thermal conductivity
Silver itself is one of the most conductive metals, and nano silver powder inherits this advantage. While maintaining good conductivity, its nanoscale effect also brings special electrical properties, such as quantum tunneling effect that may occur at low temperatures.
3. Unique optical properties
Due to the surface plasmon resonance effect, nano silver powder has strong absorption and scattering abilities for light. This makes its color not silver white, but yellow, brown, or even black depending on the particle size.
4. Quantum size effect
When the particle size decreases to the nanometer level, its energy level changes from a continuous band to a discrete energy level, exhibiting completely different characteristics from macroscopic matter in terms of magnetism, light, electricity, and so on.
Preparation method
In order to obtain nano silver powder with stable performance and uniform particle size, the following methods are usually used:
1. Liquid phase reduction method: A reducing agent is added to a silver salt solution (such as silver nitrate) to reduce silver ions to elemental silver by controlling temperature, pH, and other conditions. This method is widely used and can prevent particle agglomeration by adding dispersants.
2. High energy ball milling method: using mechanical force to crush silver powder or silver blocks from micrometer level to nanometer level.
3. Laser ablation method: Pulsed laser is used to irradiate a metal silver target, forming nanoparticles in the liquid. The particles prepared by this method are pure and highly stable.
4. Atomization method: The molten silver liquid is crushed by high-pressure airflow and then cooled to form nano-sized particles.
Application scope of silver powder:
1) Conductive paste: Preparation of electronic paste for wiring, packaging, and connection in the production of microelectronic components, enabling miniaturization of microelectronic devices and miniaturization of circuits.
2) Antibacterial and antivirus: Various additives such as paper, plastic, textiles, coatings, etc. are used for antibacterial and antivirus purposes. Nano layered silver based inorganic antibacterial powder with a concentration of about 0.01-0.1% has strong inhibitory and killing effects on dozens of pathogenic microorganisms such as Escherichia coli and Staphylococcus aureus. As a brand new anti infection product, it has various properties such as broad-spectrum, no drug resistance, not affected by pH value, long-lasting antibacterial, and non oxidizing blackening. It can be successfully used in architecture, cultural relic protection, and medical products. Compared with ordinary silver powder, nano silver has unique surface effects, volume effects, quantum size effects, and macroscopic quantum tunneling effects that are characteristic of nanomaterials. It has strong inhibitory and killing effects on dozens of pathogenic microorganisms such as Escherichia coli, Neisseria gonorrhoeae, and Chlamydia trachomatis, and does not develop drug resistance.
3) Low temperature conductive silver paste, conductive adhesive, conductive coating, conductive ink, and the main electrode material for electronic components.
SAT NANO is a best supplier of silver powder in China, we can supply micro particle and nanoparticle in China, if you have enquiry, please feel free to contact us at sales03@satnano.com
