Electrochemical reforming of alcohols on nanostructured platinum-tin catalyst-electrodes

• Published in: Applied catalysis. B, Environmental Environmental, 2015-12, Vol.179, p.276-284
• Main Authors: de la Osa, A.R., Calcerrada, A.B., Valverde, J.L., Baranova, E.A., de Lucas-Consuegra, A.
• Format: Article
• Language: English
• Subjects: Alcohols; Anodic; Catalysts; Electrochemical reforming; Ethanol electrolysis; H2 production; Nanostructure; PEM; Platinum; Polyols; Pt–Sn catalysts; Reforming; X-ray photoelectron spectroscopy
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2015.05.026

[Display omitted] •PEM electrochemical reforming of alcohols was developed for pure H2 production.•Nanostructured Pt–Sn/C synthesized by polyol reduction method was used as anode.•The main reaction conditions were experimentally optimized for each molecule.•Electrocatalytic activity of Pt–Sn/C was comparable to commercial Pt–Ru/C catalyst. This study reports the feasibility of high purity H2 production by means of the electrochemical reforming of biomass derived organic alcohols (methanol, ethanol and ethylene glycol)-water solutions in a proton exchange membrane (PEM) electrolysis cell. For that purpose, a nanostructured bimetallic carbon-supported Pt–Sn catalyst, with nominal Pt/Sn atomic ratios of 70/30, was synthesized by a modified polyol reduction method and characterized by means of TEM, XRD and XPS analysis. The resulting Pt7–Sn3/C catalyst consists of a bi-phase Pt/SnOx structure and presents a narrow particle size distribution with size predominantly in the order of 4.5nm, showing high dispersion on carbon support (20wt.% metal loading). During electrochemical reforming tests, the influence of reaction temperature and the electrocatalytic stability of the system were verified for mild working operation times. Synthesized 20wt.% Pt7–Sn3/C anodic catalyst provided a promising electro-catalytic activity, comparable to that of commercial 60wt.% Pt–Ru/C and required lower amounts of Pt in order to produce the same amount of hydrogen. Proposed system allowed to produce H2 with a lower electrical energy requirement (26kWhkgH2−1 even after deactivation), in comparison with commercial PEM water electrolyser stacks (50kWhkgH2−1). In addition, obtained H2 purity was very high (99.938%) and only few ppm of CO and CO2 were detected at the cathode chamber. These results demonstrated the potential interest of Pt7–Sn3/C anodic catalyst, synthesized via the polyol method, for production of pure hydrogen from biomass-derived compounds via electrochemical reforming at low temperatures.