We explore an alternative synthesis of colloidal metal nanoparticles (cMnP) by electrocrystallization. The principle is to make grow long metallic ramified branches by galvanostatic electrolysis of a stagnant metal salt aqueous solution inside a Hele-Shaw (thin gap) cell. In the absence of supporting electrolyte, the constraint of electroneutrality forces the deposit to grow as ramified branches. These branches grow by successive nucleation / growth events that leads to a fine branches structure made up of metal crystals whose size can be lower than 100 nm. The objectives of this work are to study the formation mechanism of such metal nanocrystals assemblies and elaborate a device able to dissociate and release them to propose an alternative synthesis of cMnP
