Patent ID: 8434704

Claim:
A method of producing inorganic semiconducting nanoparticles having a stable surface, the method comprising: providing an inorganic bulk semiconductor material; and milling the bulk semiconductor material at a temperature of between 100° C. and 200° C. in the presence of a selected reducing agent, the reducing agent acting to chemically reduce oxides of one or more component elements of the semiconductor material formed during the milling, or prevent the formation of such oxides by being preferentially oxidised, thereby to produce semiconducting nanoparticles of the inorganic bulk semiconductor material, said nanoparticles having a stable surface which allows electrical contact between the nanoparticles, wherein the milling media and/or one or more components of the mill comprise the selected reducing agent, said selected reducing agent being a metal selected from the group consisting of iron, chromium, cobalt, nickel, tin, titanium, tungsten, vanadium, aluminium, and an alloy containing one or more of said metals.