Sub-1 nm PtSn ultrathin sheet as an extraordinary electrocatalyst for methanol and ethanol oxidation reactions

Advanced Catalytic Materials for Ethanol Oxidation in Direct Ethanol Fuel Cells

“…Moreover, the solution colloidal method has been used to synthesize sub-1 nm PtSn ultrathin sheets with the diameter in the range of 200 nm-1 µm (Figure 2a,b). The achieved ultrathin PtSn nanosheets exhibited an advanced mass activity of 673.6 mA mg Pt −1 in EOR, more than five times higher than commercial Pt black ( Figure 2f) [41]. This result is among the highest activity towards EOR for PtSn-alloyed electrocatalysts [45].…”

“…This is an effective way to reduce the overall cost of catalysts and to improve their durability performance in DEFCs, which can be ascribed to the induced lattice mismatch and modification of electronic properties via the interaction between different components. To date, diverse Pt-based alloys have been synthesized by alloying with oxyphilic atoms, such as Sn [41], Bi [19], Cu [17], Zn [42], etc. In particular, bimetallic PtSn alloys exhibit advanced catalytic activity for EOR in both acidic and alkaline media due to the bifunctional mechanism, i.e., Sn can supply -OH species (by accelerating the dissociative adsorption of water ) at relatively low overpotentials that facilitate the oxidation of intermediates [41].…”

“…To date, diverse Pt-based alloys have been synthesized by alloying with oxyphilic atoms, such as Sn [41], Bi [19], Cu [17], Zn [42], etc. In particular, bimetallic PtSn alloys exhibit advanced catalytic activity for EOR in both acidic and alkaline media due to the bifunctional mechanism, i.e., Sn can supply -OH species (by accelerating the dissociative adsorption of water ) at relatively low overpotentials that facilitate the oxidation of intermediates [41]. Moreover, the Sn-induced alternation of Pt electronic structure can weaken the bonding between Pt and poisonous CO species produced during the EOR process [43].…”

“…For example, ultrathin Pt nanowires outperform Pt nanoparticles in the EOR process due to the more abundant active sites exposed for ultrathin Pt nanowires. It is noteworthy that partial substitution of Sn for Pt can promote the formation of oxygenated species at a relatively low potential, which can alleviate the poisoning effect through the reaction between oxygen-containing groups and CO intermediates [41]. Thus, PtSn alloys often demonstrate accelerated ethanol electro-oxidation.…”

An In Situ Quick X‐ray Absorption Spectroscopy Study on Pt3Sn/Graphene Catalyst for Ethanol Oxidation Reaction

“…When Sn oxide is present, it can improve adsorption and dissociation during the oxidation reaction with an appropriate expansion of the lattice parameters in the PtSn alloy [32] . Moreover, it might enhance the complete oxidation of adsorbed CO to CO 2 and consequently promote the electrochemical activity of SnO 2 on the catalyst surface [33] …”