An electrochemical process for preparing a compound comprising a metal or metalloid and a peroxide, ionic or radical species

An electrochemical process for recovering reaction products of a metal element or a metalloid element or a mixture of two or more thereof from at least one water soluble precursor compound comprising the metal element or the metalloid element or two or more thereof, in the form of nano particles, in particular nano crystals of at least one reaction product, wherein the process comprises:

• supplying a solution of the water soluble precursor compound to a water-based catholyte of a cathode compartment of an electrochemical cell, equipped with a cathode comprising a gas diffusion electrode, wherein the gas diffusion electrode comprises a porous electrochemically active material having a BET surface area of at least 50 m2/g,
• adjusting the pH of the catholyte to a pH which is smaller than the pKa of the water soluble precursor compound,
• supplying at least one oxidant gas to the gas diffusion electrode,
• subjecting the cathode to an electrochemical potential to cause reduction of the at least one oxidant gas to one or more of the corresponding peroxide, ionic and/or radical reactive species capable of reacting with a cation comprising the metal element, or the metalloid element or the mixture of two or more thereof, to nano particles of the at least one reaction product with an average particle size, in particular nano crystals with an average crystallite size, equal to or smaller than 30.0 nm.