PROCESS FOR PURIFYING METAL NANOWIRES

摘要

Isolating metal nanowires from a reaction mixture also containing ancillary inorganic particles distinct from the nanowires, includes: providing a mixture of metal nanowires with large particles having at least two dimensions 250 nm or more, and small particles of which the largest dimension is less than 200 nm, in the form of a dispersion in a solvent medium having a viscosity at 25° C. 10 mPa·s or more; leaving the mixture to settle out under conditions conducive to the formation of a supernatent phase including the small particles and of a precipitate comprising the metal nanowires and the large particles; isolating the precipitate, and dispersing the isolated precipitate in a solvent medium having a viscosity at 25° C. less than 10 mPa·s; leaving the suspension to settle out under conditions conducive to the precipitation of said large particles; and recovering the nanowires in the form of a dispersion in the supernatent phase.

主权项

1. A process useful for isolating metal nanowires from a reaction mixture for the synthesis thereof, the reaction mixture also containing ancillary inorganic particles distinct from the nanowires, the method comprising:
(i) providing a mixture of metal nanowires with large particles having at least two dimensions greater than or equal to 250 nm, and small particles of which the largest dimension is strictly less than 200 nm, in the form of a dispersion in a solvent medium S1 having a viscosity at 25° C. greater than or equal to 10 mPa·s; (ii) leaving said mixture to settle out under conditions conducive to the formation of a supernatent phase comprising said small particles and of a precipitate comprising the metal nanowires and said large particles; (iii) isolating the precipitate obtained at the end of the settling out (ii), and dispersing the isolated precipitate in a solvent medium S2 having a viscosity at 25° C. strictly less than 10 mPa·s; (iv) leaving the suspension formed in step (iii) to settle out under conditions conducive to the precipitation of said large particles; and (v) recovering the nanowires in the form of a dispersion in the supernatent phase obtained at the end of the settling out (iv).