Electrochemical impedance spectroscopy (EIS) is a well-established method to analyze polymer electrolyte membrane fuel cell (PEMFC). However, without further data processing, the spectrum yields only qualitative insight into mechanism and individual contribution of transport, kinetics, ohmic losses overall limitations. The distribution relaxation times (DRT) allows quantifying each these polari...

A simple approach for the screening of oxygen evolution reaction (OER) electrocatalyst arrays by scanning electrochemical microscopy (SECM) in the substrate generation/tip collection (SG/TC) mode is described. The methodology is based on the application of a series (9−10 replicates) of double-potential steps to a catalytically active substrate electrode, which is switched between potentials whe...

Oxygen evolution electrocatalysts in acidic media were studied by scanning electrochemical microscopy (SECM) in the substrate generation-tip collection (SG-TC) imaging mode with a 100 microm diam tip. Pure IrO2 and Sn(1-x)Ir(x)O2 combinatorial mixtures were prepared by a sol-gel route to form arrays of electrocatalyst spots. The experimental setup has been developed to optimize screening of ele...

Ethanol, with its high energy density, likely production from renewable sources and ease of storage and transportation, is almost the ideal combustible for fuel cells wherein its chemical energy can be converted directly into electrical energy. However, commercialization of direct ethanol fuel cells has been impeded by ethanol's slow, inefficient oxidation even at the best electrocatalysts. We ...

-Localization of Pt electrocatalyst by sputter deposition of a thin film (5OOA) on the front surface of a fuel cell electrode containing a supported electrocatalyst (20% Pt/C, 0.4mgcm-* loading) has been known to exhibit higher fuel cell performance as compared to that on the electrode without the sputtered flm. This study compares the electrode kinetic parameters, electrochemically active surf...

Single-wall and multiwall carbon nanotubes are employed as carbon supports in direct methanol fuel cells (DMFC). The morphology and electrochemical activity of single-wall and multiwall carbon nanotubes obtained from different sources have been examined to probe the influence of carbon support on the overall performance of DMFC. The improved activity of the Pt-Ru catalyst dispersed on carbon na...

A hierarchical excavated iron-nitrogen codoped mesoporous carbon (Ex-FeN-MC) electrocatalyst has been successfully synthesized by pyrolysis of the unique ureidopyrimidinone containing organic precursor MAMIS by using silica as the mesoporous template and iron nitrate as the source of iron. The selected organic precursor has multifunctionalities with diverse distribution of nitrogen and oxygen s...

Searching for metal-free catalysts for the carbon dioxide reduction reaction (CO2RR) has been a key challenge in the electrosynthesis of fuels for CO2 utilization. In this work, we investigated the potential of N-doped graphene as the electrocatalyst of CO2RR by means of comprehensive density functional theory (DFT) computations. The computations revealed that N-doping can modify the electronic...