Binary electrocatalysts for organic oxidations

A comparative study on ethanol oxidation behavior at Pt and PtRh electrodeposits

“…The oxidation of PtRh surfaces commences at more negative potentials than that observed for Pt. With increasing Rh content, the surface oxidation current rises in the potential region of À0.4 to +0.2 V. However, in approximately the same potential region, there is a diminution of the corresponding oxide reduction current, until for Pt 74 Rh 26 Fig. 1.…”

“…The profile for the electrooxidation of ethanol on Pt 35 Rh 65 electrode is quite different and shows a single oxidation peak centered at around 0.2 V. The absence of a second oxidation peak can be interpreted as the inability of a rhodium-rich surface to transfer oxygen at relatively high potentials. Koch et al reported a deactivation of the PtRh alloy for methanol oxidation when significant amount of oxygen is adsorbed on the surface at higher potentials [26]. Unlike the other electrodes, a large hydrogen adsorption-desorption current is observed on the Pt 35 Rh 65 alloy surface.…”

Applications of high throughput (combinatorial) methodologies to electronic, magnetic, optical, and energy-related materials

“…[349][350][351][352] Ink jet based solution synthesis techniques, in which metal salts are solution deposited onto an electrode, have also been employed. [353][354][355] The arrays are then reduced to the metallic state, frequently by borohydrides such as NaBH 4 . One concern with the uniform usage of NaBH 4 as a reducing agent is its inability to provide the high surface area catalysts eventually required for implementation.…”

“…One concern with the uniform usage of NaBH 4 as a reducing agent is its inability to provide the high surface area catalysts eventually required for implementation. 355 Another technique is wet impregnation, followed by calcination at high temperatures to promote oxidation and mixing. 356,357 Other groups employ electrodeposition, in which a fluid containing the catalyst precursors is pipetted onto an array of electrodes, followed by the electrodeposion of the catalyst on the electrode surface using a potentionstat, 358 Fig.…”

“…The combination of Pt with an oxophilic material, such as Ru, can alleviate this problem. 355 When Ru is substituted into Pt, it has a tendency to be leached from the surface of the catalyst during electrochemical cycling. To circumvent this issue, the ordered intermetallic phases PtBi and PtPb have recently come to attention.…”