Alcohol reduction process

The alcohol reduction process invented by Hirai and Toshima is widely applicable for the preparation of colloidal precious metals stabilized by organic pol5mers such... 

PtSn/C electrocatalysts with R Sn atomic ratios of 50 50 and 90 10 were prepared by alcohol-reduction process, using ethylene glycol as solvent and reducing agent, and by borohydride reduction. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electro-oxidation of ethanol was studied by cyclic voltammetry using the thin porous coating technique. The electrocatalysts performance depends greatly on preparation procedures and R Sn atomic ratios. 

Pt/C and PtiRui/C electrocatalysts prepared by alcohol reduction process... 

Recently, our group has invented a modified successive alcohol reduction process to prepare inverted core/shell structured bimetallic nanoclusters. In practice, PVP-capped Pd-core/Pt-shell bimetallic nanoclusters 2 nm in size were obtained. This method is based on the fact that precious metals like Pd have the ability to adsorb hydrogen and split it to form metal hydride on the surface of a precious metal. Hydride on precious metal has a very strong reducing ability, implying a quite low redox potential. As illustrated in Fig. 3.23, the Pt ions added into the dispersion of Pd nanoclusters are reduced by hydride on the surface of preformed Pd nanoclusters without oxidizing Pd atoms to Pd ions, and are deposited on the Pd nanoclusters to form Pd-core/Pt-shell bimetallic nanoclusters. Since the coreduction of Pd and Pt ions produces only Pt-core/Pd-shell bimetallic nanoclusters and this structure is controlled by nature, Pt-core/Pd-shell can be called a normal core/shell structure. The structure of Pd-core/Pt-shell is opposite to the normal structure. Thus, we call this an inverted core/shell structure. 

Fig. 6.6 Alcohol-reduction process of PVP-stabilizKd metal nanopaiticles...

Neto AO, Dias RR, Tusi MM, Linardi M, Spinace EV (2007) Electro-oxidation of methanol and ethanol using PtRu/C, PtSn/C and PtSnRu/C electrocatalysts prepared by an alcohol-reduction process. J Power Sources 166 87-91... 

Well-dispersed ternary PtRuSn catalysts of various atomic ratios (60 30 10, 60 20 20, and 60 10 30) were deposited onto carbon using a modified alcohol-reduction process by Wu et al. [303]. The alloy phase structure and surface morphology for each variation of the PtRuSn/C catalysts were determined by XRD and HR-TEM. In order to evaluate the contributions of Ru and Sn in the different stages of ethanol oxidation, electrochemical oxidations of adsorbed CO, ethanol, acetaldehyde, and acetic acid were performed on each PtRuSn/C catalyst. The results indicated that the Ru-rich PtRuSn/C catalyst (60 30 10) exhibited the lowest... 

Neto AO, Vasconcelos TRR, Da Silva RWRV, Linardi M, Spinace EV. Electrooxidation of ethylene glycol on PtRn/C and PtSn/C electrocatalysts prepared by alcohol-reduction process. J Appl Electrochem 2005 35 193-8. 

Wu G, Swaidan R, Cui G. Electrooxidations of ethanol, acetaldehyde and acetic acid using PtRuSn/C catalysts prepared by modified alcohol-reduction process. J Power Sources 2007 172 180-8. 

The current state-of-the-art carbon supported electro-catalyst is made using variants of the colloidal approach. A common approach is to dissolve the metal salt solution in an appropriate solvent followed by reduction, to form a colloidal. A wide variety of recipes using reducing agents, organic stabilizers, or shell-removing approaches have also been developed in recent years. Among colloidal processes, the alcohol reduction process by Toshima and Yonezawa (1998) is widely applicable for the preparation of colloidal precious metals of small and uniform... 

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