PdSn nanocatalysts supported on carbon nanotubes synthesized in deep eutectic solvents with high activity for formic acid electrooxidation

Abstract

Deep eutectic solvents (DESs) are being increasingly used in electrochemically controllable synthesis of functional nanomaterials because of their unique merits (e.g., high conductivity, wide electrochemical windows and environmental friendship). Herein, we report a novel strategy in DESs for the fabrication of multi-walled carbon nanotubes (MWCNTs)-supported Pd-based alloy nanostructures. Using a NaBH 4 solvothermal reduction process in DESs, highly active PdSn alloy nanocatalysts supported on MWCNTs towards the formic acid oxidation (FAO) reaction were synthesized for the first time. The as-synthesized materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS) and electrochemical tests.The results demonstrate that the PdSn nanocluster structure with a rough surface provides a high density of catalytically active sites and thereby increases the electrochemically active surface area. There is a strong charge transfer interaction between Pd and Sn in the PdSn/MWCNT catalyst due to its high degree of alloying. The electrochemical studies indicate that the PdSn/MWCNT shows remarkably improved electrocatalytic performance towards FAO compared to Pd/MWCNT and commercial Pd/C catalysts. This study suggests an effective synthesis strategy for Pd-based electrocatalysts with high performance for DFAFCs applications.

Porous three-dimensional network of Pd–Cu aerogel toward formic acid oxidation

“…The intense decay in current density because of the production and adsorption of intermediate carbonaceous species on the catalysts surface goes along with the block of active sites as well as poisoning of catalysts surface. [30][31][32][33][34][35][36][37][38][39][40] Aer an early intense drop in performance, the current densities were stabilized at 5.2 and 45.6 mA cm À2 for Pd/C and Pd-Cu aerogel, respectively. The very high catalytic activity and durability of the Pd-Cu aerogel than that of Pd/C are attributed to the two vital reasons: (1) the presence of abundant open pores as well as easy access to large active sites of Pd-Cu aerogel, and (2) the selfsupporting property of the Pd-Cu aerogel, which may hinder the loss of stability observed in Pd supported on carbon owing to corrosion.…”

Enhanced Formic Acid Oxidation over SnO2-decorated Pd Nanocubes

“…However, a limitation of the shaped NPs is their morphological instability. , It has been reported that monometallic Pd catalysts deactivate and degrade by dissolution of Pd under acidic operation conditions, ,, and, thus, the preservation and optimization of the activity and stability of the catalyst is of crucial interest. Therefore, the addition of a second metal, such as Au, , Pt, Ag, Ti, Pb, Fe, or Sn, ,,− provides a common strategy for enhancing the activity and stability of Pd-based catalysts. Most known Pd-M catalysts form alloys, which not only lead to a variation of the reaction mechanism, but also generally improve the stability …”

Mn-doped nickeltitanate (Ni1−xMnxTiO3) as a promising support material for PdSn electrocatalysts for methanol oxidation in alkaline media

“…It improves the electrocatalytic activity and stability of the PdSn–MNT/C. 42 The synergetic effect of binary metal catalyst produces higher peak current density for the PdSN–MNT/C electrode. This experiment is in good accord with the published literature on other metal oxides promoted for the MOR.…”