Control of crystallographic phases and surface characterization of intermetallic platinum tin nanoparticles

Abstract

Colloidal synthesis and characterization of intermetallic tin-rich platinum–tin nanoparticles with detailed surface characterization.

Phase-Controlled Synthesis of Pd–Sn Nanocrystal Catalysts of Defined Size and Shape

“…After doing XPS sputter depth profiling, the peaks corresponding to metallic Sn appeared higher in intensity, indicating the removal of Sn (II/IV) which likely exists in the form of SnO x on the surface of the Pd–Sn NPs, which is typically found in Sn-based alloys (Figure S10). − These results are consistent with a shell observed at high magnification TEM and the presence of oxygen identified by STEM/EDS (Figure S11 and 12). The importance of this surface characterization will be discussed in the context of the Pd–Sn NPs toward FAEO.…”

Synthesis of PtSn4 Intermetallic Nanodisks through a Galvanic Replacement Mechanism

“…20,21 Pt−Sn intermetallic NPs, especially pure-phase PtSn 4 intermetallic NPs, can rarely be synthesized from Pt NP seeds using this method. 18,22 To access Sn-rich Pt−Sn intermetallic phases, it is natural to start with Sn NP seeds and control the amount of Pt that will be reduced and incorporated. 23 We envision that a galvanic replacement reaction between Pt ions and metallic Sn seeds is an ideal method to localize the reduction of Pt to be only at the Sn NP surface, avoiding the formation of free Pt NPs.…”

“…PtSn 4 is the low-temperature stable phase in the Pt–Sn intermetallic system. The preparation of pure-phase PtSn 4 nanomaterials is very challenging due to the competition with other phases, which has not been successfully demonstrated to the best of our knowledge. − …”

“…Most reported methods for synthesizing Pt–Sn intermetallic nanoparticles (NPs) start with Pt NP seeds that catalyze the reduction of Sn ions with polyol as the reducing agent, which prevents the formation of free Sn NPs. , However, Sn-rich Pt–Sn intermetallic NPs, especially pure-phase PtSn 4 intermetallic NPs, can rarely be synthesized from Pt NP seeds using this method. , To access Sn-rich Pt–Sn intermetallic phases, it is natural to start with Sn NP seeds and control the amount of Pt that will be reduced and incorporated . We envision that a galvanic replacement reaction between Pt ions and metallic Sn seeds is an ideal method to localize the reduction of Pt to be only at the Sn NP surface, avoiding the formation of free Pt NPs.…”

Preparação de catalisadores Pt/CeO2 via método de redução por álcool para a oxidação preferencial de monóxido de carbono em misturas ricas em hidrogênio (PROX-CO)

“…Além disso, os nanocristais de platina e estanho fornecem melhor tolerância à presença do monóxido de carbono sobre os sítios de platina do que em relação à platina pura (ERDT et al, 2019 SPINACÉ et al, 2008;NETO et al, 2010;SILVA, D. et al, 2010;AYOUB et al, 2011;GERALDES et al, 2015). (PITUSSI et al, 2020), sugere uma maneira eficaz de produzir catalisadores bimetálicos mais ativos para uso em reações catalíticas de oxidação, tais como a reação de PROX-CO. Adicionalmente, foi preparado um catalisador contendo fração mássica de 1 %…”