US 12,251,756 B2
Method for preparation of a supported noble metal-metal alloy composite, and the obtained supported noble metal-metal alloy composite
Matija Gatalo, Ljubljana (SI); Nejc Hodnik, Ljubljana (SI); Marjan Bele, Ljubljana (SI); and Miran Gaberšcek, Domžale (SI)
Assigned to KEMIJSKI INSTITUT, Ljubljana (SI)
Appl. No. 17/438,511
Filed by KEMIJSKI INŠTITUT, Ljubljana (SI)
PCT Filed Mar. 17, 2020, PCT No. PCT/EP2020/057334
§ 371(c)(1), (2) Date Sep. 13, 2021,
PCT Pub. No. WO2020/187933, PCT Pub. Date Sep. 24, 2020.
Claims priority of application No. 101157 (LU), filed on Mar. 18, 2019.
Prior Publication US 2022/0143691 A1, May 12, 2022
Int. Cl. B22F 9/24 (2006.01); B22F 1/054 (2022.01); B22F 1/18 (2022.01); B82Y 40/00 (2011.01); B82Y 30/00 (2011.01)
CPC B22F 1/054 (2022.01) [B22F 1/18 (2022.01); B22F 9/24 (2013.01); B82Y 40/00 (2013.01); B22F 2301/10 (2013.01); B22F 2301/25 (2013.01); B22F 2302/40 (2013.01); B22F 2304/054 (2013.01); B82Y 30/00 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method for forming supported noble metal nanoparticles and/or noble metal-M alloy nanoparticles composite, M being a less noble metal galvanically displaced to deposit the noble metal, the method comprising the following steps:
(a) providing a M/S precursor material of metal particles, M, on electrical conductive support particles, S, where M is one or more metal having lower standard electrode potential than the noble metal, wherein the support particles have an electrical conductivity larger than any formed passivating M-oxide layer of the metal M deposited thereon;
(b) suspending the M/S precursor material in a liquid medium, the liquid medium having a pH at which an in-situ passivating oxide is thermodynamically formed at least on the surface of the metal M particles being exposed to the liquid medium, forming a passivated MOy/S suspension, y being >0 up to a stoichiometric M-oxide value;
(c) providing an adsorptive gas to the MOy/S suspension in the same liquid medium as step (b), the adsorptive gas being selectively adsorbable on the noble metal to be deposited;
(d) adding a noble metal precursor to the MOy/S suspension in the same liquid medium as step (c), thereby depositing as a reaction product crystalline noble metal nanoparticles and/or crystalline noble metal-M alloy nanoparticles on the support particles by a galvanic displacement reaction; and
(e) separating and washing the as-synthesized reaction product.