Metal and Alloy Nanoparticle Production through Cathodic Corrosion
Leiden University has developed a radically different method for large scale production of diverse metal nanoparticles and their alloys. The size of nanoparticles range from 2 – 100 nm in liquids.
A Proof of Principle has been demonstrated and a larger production unit became operational recently. The new unit will make it possible to provide research institutes and industry samples for further evaluation.
Cathodic corrosion for producing nanoparticles was (re)discovered when trying to control the electrochemical etching of a scanning tunneling microscopy (STM) tip. We have shown that the metal nanoparticles (NPs) and their alloys can be easily produced by using cathodic corrosion and their sizes and compositions can be controlled. The produced NPs were shown to have high catalytic activity and superior to the commercial ones. Since cathodic corrosion is radically different from all other existing methods of NP synthesis, its ability for tuning properties of NPs is still relatively unexplored, and hence improved characteristics are still expected. Given the enormous simplicity and versatility of the method, we believe that cathodic corrosion has unique potential.
This method includes also the inhibition of agglomeration, the scaling up of NP production and the in-situ impregnation of functional nanocomposites.
More information is to be found in the following scientific publications:
Figure 1. Photographs of the colloidal nanoparticles (NPs) generated by the cathodic corrosion method. (a) monometallic Au, Pt, Ag, Pd, Ir, Cu, and binary PtAu and PdAu alloy nanoparticles (NPs); (b) AgxAu100-x (atomic ratio) nanoalloys with x = 10, 30, 50, 70, and 90.
Figure 2. Schematic illustration of the ‘comb-electrode’ setup for the cathodic corrosion method . The block diagram of the global design of the setup (a), the complete cell system (b), the electrode feeding component (c) and an enlarged ‘comb’ consisting of 5 electrode pairs (d). A micrometer screw mounted on the comb electrodes was used to precisely adjust their submersion depth (measured from the moment the electrode touches the liquid surface) in the liquid.
This new electrochemical method is advantageous to other nanoparticle production methods:
- Simple and easily scalable
- Cost effective
- Versatile: all metals, metal alloys, oxides can be produced
- Precisely engineered sizes, compositions, shapes, and dispersity
- High purity
- Compatible with industrial lines
- Unique (combine central features from both ‘dry’ aerosol and wet-chemistry methods)
Producing an extensive variety of nanoparticles and their alloys makes this method unique for almost all applications among:
- Conductive inks
- Antibacterial applications (low-cost sub-10-nm silver nanoparticles)
Development has also started for some initial ideas for implementing CCM in industrial production processes, such as producing catalysts.
Luris reference numberINV-015.008
Patent rights are being acquired in EU, USA, Japan and China.