Carbon-Supported Pt-SnO2 Catalysts for Oxygen Reduction Reaction over a Wide Temperature Range: Rotating Disk Electrode Study

Abstract

Pt/C and Pt/x-SnO2/C catalysts (where x is mass content of SnO2) were synthesized using a polyol method. Their kinetic properties towards oxygen reduction reaction were studied by a rotating disk electrode (RDE) technique in a temperature range from 1 to 50 °C. The SnO2 content of catalyst samples was 5 and 10 wt.%. A quick evaluation of the catalyst activity, electrochemical behavior and average number of transferred electrons were performed using the RDE technique. It has been shown that the use of x-SnO2 (through modification of the carbon support) in a binary system together with Pt does not reduce the catalyst activity in the temperature range of 1–30 °C. The temperature rising up to 50 °C resulted in composite catalyst activity reduction at about 30%.

Study of the Cathode Pt-Electrocatalysts Based on Reduced Graphene Oxide with Pt-SnO2 Hetero-Clusters

“…The mass (Ma) and specific (Sa) activities of the Pt 20 /SnO2 10 /c-RGO in the oxygen reduction reaction were 0.23 mA cm −2 and 192 mA mg −1 , respectively. Compared with Pt 20 /C (Sa = 0.25 mA cm −2 , Ma = 207 mA mg −1 [7]), Pt 20 /SnO2 10 /c-RGO showed slightly lower activities due to the close packing of RGO sheets, making it difficult for oxygen to diffuse into the active sites [36]. The catalysts modified with tin dioxide demonstrated high activity despite the partial blockage of Pt active sites by SnO2 nanoparticles.…”

“…The relatively high activity of the composite catalyst was explained by the participation of tin dioxide in the ORR as a co-catalyst. Thus, both platinum and tin dioxide particles are emphasized as active sites [7].…”

“…Activity in the oxygen reduction reaction (ORR) was determined by rotating disk electrode methods in 0.1 M HClO 4 . The technique for studying the activity of electrocatalysts in the ORR is described in detail in [7].…”

“…The high durability of the Pt-SnO 2 -based catalysts is attributed to the strong metal-support interaction (SMSI) that inhibits the migration and agglomeration of the nanoparticles at the electrode surface. Previously, it was shown that the Pt 20 /SnO 2 10 /C electrocatalyst demonstrates increased stability during accelerated stress tests (AST) due to the high stability of SnO 2 particles (10 wt.%) and their interaction with Pt [6,7]. However, the use of SnO 2 lowers both the electrical conductivity of the electrocatalyst due to the semiconductor properties of SnO 2 and the electrochemical surface area (ESA) due to the high degree of particle agglomeration.…”

SAXS Investigation of the Effect of Freeze/Thaw Cycles on the Nanostructure of Nafion® Membranes

“…Inorganic hydrophilic compounds are widely used as water sorbents in the development of PEMFCs that are stable at low humidity; both catalytic layers [ 24 , 25 , 26 , 27 , 28 ] and membranes [ 21 , 29 , 30 , 31 , 32 , 33 ] can be modified. Membrane modification results in a greater water retention effect, but introduction of a sorbent leads to an increase in the ionic resistivity, resulting in PEMFC performance degradation [ 34 ].…”