Sn@Pt and Rh@Pt core–shell nanoparticles synthesis for glycerol oxidation

Abstract

The development and optimization of electrocatalysts for application in fuel cell systems have been the focus of a variety of studies where core-shell structures have been considered as a promising alternative among the materials studied. We synthesized core-shell nanoparticles of Sn x @Pt y and Rh x @Pt y (Sn@Pt, Sn@Pt 2 , Sn@Pt 3 , Rh@Pt, Rh@Pt 2 , and Rh@Pt 3 ) through a reduction methodology using sodium borohydride. These nanoparticles were electrochemically characterized by cyclic voltammetry and further analyzed by cyclic voltammetry studying their catalytic activity toward glycerol electro-oxidation; chronoamperometry and potentiostatic polarization experiments were also carried out. The physical characterization was carried out by X-ray diffraction, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The onset potential for glycerol oxidation was shifted in 130 and 120 mV on the Sn@Pt 3 /C and Rh@Pt 3 /C catalysts, respectively, compared to commercial Pt/C, while the stationary pseudo-current density, taken at 600 mV, increased 2-fold and 5-fold for these catalysts related to Pt/C, respectively. Thus, the catalysts synthesized by the developed methodology have enhanced catalytic activity toward the electro-oxidation of glycerol, representing an interesting alternative for fuel cell systems.

An Overview of Glycerol Electrooxidation Mechanisms on Pt, Pd and Au

“…The tailoring of GEOR with different ad‐metals has been extensively studied. Rh shows little promotion on the catalytic efficiency [12] and C−C bond cleavage [170,171] when alloyed with Pt (still under debate [2,172] ), whereas it facilitates the C−C bond cleavage on Pd [130] . Additionally, Rh shows reactivity through primary carbon oxidation and C−C bond dissociation on its own [173] .…”

Recent Progress in Electrocatalytic Glycerol Oxidation

“…[ 50 ] For instance, introducing non‐noble metals such as Ni, [ 51 ] Cu, [ 52 ] Sn, [ 53 ] and Bi [ 54 ] into Pt metal greatly enhanced their catalytic performance owing to the electronic interaction between the platinum and the other metals. [ 55 ] Recently, Zhao et al prepared a series of dealloyed PtPd‐based alloy particles (PtPd‐ x /C, x stands for Fe content in PtPdFe precursor, x = 0, 2, 4, 6, 8, 10) by etching PtPdFe precursor. Such structures effectively improved the utilization efficiency unit of PtPd and promoted the electro‐oxidation of glycerol, [ 18 ] with a large ECSA of 113.33 cm 2 mg PtPd −1 , the maximum oxidation peak current of 0.86 A mg PtPd −1 , a good stability with only 5.8% current decrease after 400 cycles, and excellent CO tolerance.…”

An FTIR Study of the Electrooxidation of C2 and C3 Alcohols on Carbon‐Supported PdxRhy in Alkaline Medium**

“…To confirm this effect, we estimated the crystal lattice parameter (a hkl ) of each catalyst as described previously. [11,45] Figure S2b shows the relation between the lattice parameter and the Rh content in the catalysts. Above 20 % Rh content, the lattice parameter values decreased linearly, indicating alloy formation according to the Vegard's law (Table 1).…”