Rhodium Nanoparticle-Loaded Carbon Black Electrocatalyst for the Glycerol Oxidation Reaction in Alkaline Medium

Binh Thi Xuan Lam,Hiroshi Inoue,Masanobu Chiku,Eiji Higuchi

doi:10.4236/anp.2016.51007

Abstract

Rhodium nanoparticle-loaded carbon black (Rh/CB) was prepared by a wet method, and its activity and durability for glycerol oxidation reaction (GOR) in alkaline medium were compared with Pt, Pd and Au nanoparticle-loaded CB (Pt/CB, Pd/CB and Au/CB). In the cyclic voltammogram of the Rh/CB electrode, the redox waves due to hydrogen adsorption/desorption and the surface OH monolayer formation/reduction were observed at more negative potentials than the Pt/CB and Pd/CB electrodes. The onset and peak potentials of the GOR current densities for the Rh/CB electrode were ca. –0.55 and –0.30 V vs. Hg/HgO, respectively, which were 0.10 and 0.20 V more negative than the Pt/CB electrode whose GOR activity was the best, indicating that Rh was a fascinating metal for reducing the overpotential for GOR. In the electrostatic electrolysis with the Rh/CB and Pt/CB electrodes, the decrease in the GOR current density in the former with time was suppressed compared to that in the latter, suggesting that the tolerance to poisoning for the Rh/CB electrode was superior to that for the Pt/CB electrode.

Highlights

Biodiesel fuel (BDF) attracts attention as a carbon-neutral fuel as well as bioethanol
Direct alcohol fuel cells (DAFCs), in which methanol and ethanol are used as fuels, have attracted considerable interest because they have a high energy density and advantages of easy handling, storage, and transportation compared with pure hydrogen [1]-[4]
Rhodium nanoparticle-loaded carbon black (Rh/carbon black (CB)) was prepared by a wet method at room temperature

Summary

Introduction

Biodiesel fuel (BDF) attracts attention as a carbon-neutral fuel as well as bioethanol. Rhodium has been reported to break the C-C bond of an ethanol molecule to enhance the selective production of CO2 [12], and Pt-Rh-Sn ternary catalysts succeeded in facilitating the C-C bond cleavage [13] [14] In this way Rh is a promising metal to catalyze the C-C bond cleavage of a glycerol molecule and facilitate GOR. We have developed a wet method to prepare metal nanoparticle-loaded carbon black (CB), in which rhodium chloride was reduced by KBH4 in presence of tetraoctylammonium bromide (N(Oct)4Br) as stabilizer [18]. Its catalytic activity and stability for GOR were evaluated, and compared with the other metal catalysts

Reagents

Preparation and Characterization of Nanoparticle-Loaded Carbon Black

Results and Discussion

Conclusion