Electrolytic synthesis of metallic aluminum nanoparticles in aqueous solution

The present paper describes the preparation of metallic aluminum (Al) nanoparticles in an aqueous solution. An aqueous colloidal solution containing metallic Al nanoparticles was prepared by electrolyzing an Al salt aqueous solution using two metallic Al plate electrodes. Simultaneous electrolysis and sonication was necessary for the successful synthesis of metallic Al particles with a cubic crystal structure. Metallic Al particles were mainly produced on the cathode. Electrolysis under sonication was performed under various conditions. The morphology of the particles strongly depended on the temperature, electrolysis time, and sonication frequency, which could be mainly explained by changes in particle collision frequency and dissolution, particle collision frequency, and attenuation in the medium and/or cavitation stability, respectively. Metallic Al particles could be prepared using a stainless-steel plate as the cathode. Under the appropriate conditions, metallic Al particles with particle sizes of ca. 75–130 nm could be synthesized. Graphical Abstract