Publications by Heron Vrubel | EPFL Graph Search

Experimental correlations and integration of gas boosters in a hydrogen refueling station

Hubert Girault, Heron Vrubel, Johnny Arlettaz, Yorick Ligen

2020

Energy efficient hydrogen drying and purification for fuel cell vehicles

Hubert Girault, Heron Vrubel, Yorick Ligen

High-purity standards are required for hydrogen used in fuel cell vehicles. The relative abundance of contaminants is highly influenced by the production pathway. Hydrogen obtained from water electrolysis presents three main pollutants: Nitrogen, Oxygen an ...

Elsevier2020

Mechanistic study of the photo‐generation of hydrogen by decamethylruthenocene

Hubert Girault, Laurent Alexis Clément Vannay, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Sunny Isaïe Maye, Micheal Diarmaid Scanlon, Pekka Eero Peljo, Lucie Josette Renée Rivier

Hydrogen evolution by decamethylruthenocene (Cp*2RuII) was studied in detail highlighting that metallocenes are capable of photo‐reducing hydrogen without the need of an additional sensitizer. Electrochemical, gas chromatographic and spectroscopic (UV/vis, ...

2019

On-Site Purification of Copper-Contaminated Vanadium Electrolytes by using a Vanadium Redox Flow Battery

Hubert Girault, Heron Vrubel, Danick Reynard, Christopher Raymond Dennison, Alberto Battistel

Corrosion of carbon-based electrodes and bipolar plates is a major hurdle and can be a cause of failure in commercial vanadium redox flow batteries (VRFBs). Carbon corrosion was found to occur in a commercial VRFB (10 kW/40 kWh), whereby cracks through bip ...

WILEY-V C H VERLAG GMBH2019

Local Energy Storage and Stochastic Modeling for Ultrafast Charging Stations

Hubert Girault, Heron Vrubel, Yorick Ligen

Multi-stall fast charging stations are often thought to require megawatt-range grid connections. The power consumption profile of such stations results in high cost penalties due to monthly power peaks and expensive linkage fees. A local energy storage sys ...

2019

Polymer-Brush-Templated Three-Dimensional Molybdenum Sulfide Catalyst for Hydrogen Evolution

Harm-Anton Klok, Xile Hu, Lucas-Alexandre Stern, Heron Vrubel, Tugba Bilgiç Tune, Piotr Mocny

Earth-abundant hydrogen evolution catalysts are essential for high-efficiency solar-driven water splitting. Although a significant amount of studies have been dedicated to the development of new catalytic materials, the microscopic assembly of these materi ...

2018

Mobility from Renewable Electricity: Infrastructure Comparison for Battery and Hydrogen Fuel Cell Vehicles

Hubert Girault, Heron Vrubel, Yorick Ligen

This work presents a detailed breakdown of the energy conversion chains from intermittent electricity to a vehicle, considering battery electric vehicles (BEVs) and fuel cell electric vehicles (FCEVs). The traditional well-to-wheel analysis is adapted to a ...

MDPI2018

Redox Solid Energy Boosters for Flow Batteries: Polyaniline as a Case Study

Hubert Girault, Véronique Amstutz, Heron Vrubel, Pekka Eero Peljo, Christopher Raymond Dennison, Alberto Battistel, Elena Zanzola

In this work, the viability of polyaniline as a solid charge storage material in an aqueous redox-mediated flow battery is investigated. Fe(III/II) and V(IV/III) were identified as potential redox mediators to target the emeraldine-pernigraniline and leuco ...

Elsevier2017

Mediated water electrolysis in biphasic systems

Hubert Girault, Heron Vrubel, Micheal Diarmaid Scanlon, Pekka Eero Peljo, Lucie Josette Renée Rivier

The concept of efficient electrolysis by linking photoelectrochemical biphasic H2 evolution and water oxidation processes in the cathodic and anodic compartments of an H-cell, respectively, is introduced. Overpotentials at the cathode and anode are minimis ...

Royal Society of Chemistry2017

Boosting Water Oxidation Layer-by-Layer

Hubert Girault, Véronique Amstutz, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Micheal Diarmaid Scanlon, Jonnathan Cesar Hidalgo Acosta

Electrocatalysis of water oxidation was achieved using fluorinated tin oxide (FTO) electrodes modified with layer-by-layer deposited films consisting of bilayers of negatively charged citrate-stabilized IrO2 NPs and positively charged poly(diallyldimethyla ...

Royal Society of Chemistry2016

All-Vanadium Dual Circuit Redox Flow Battery for Renewable Hydrogen Generation and Desulfurisation

Hubert Girault, Frédéric Gumy, Véronique Amstutz, Heron Vrubel, Joana Morgado, Pekka Eero Peljo, Kathryn Ellen Toghill, Christopher Raymond Dennison, Justine Nadine Liliane Pandard

An all-vanadium dual circuit redox flow battery is an electrochemical energy storage system capable to function as a conventional battery, but also to produce hydrogen and perform desulfurization when surplus of electricity is available by chemical dischar ...

Royal Society of Chemistry2016

Catalysis of water oxidation in acetonitrile by iridium oxide nanoparticles

Hubert Girault, Véronique Amstutz, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Micheal Diarmaid Scanlon, Jonnathan Cesar Hidalgo Acosta

Water oxidation catalysed by iridium oxide nanoparticles (IrO2 NPs) in water–acetonitrile mixtures using [RuIII(bpy)3]3+ as oxidant was studied as a function of the water content, the acidity of the reaction media and the catalyst concentration. It was obs ...

2015

Chaotropic Agents Boosting the Performance of Photo-ionic Cells

Hubert Girault, Jelissa Risse, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Astrid Johana Olaya Avendano, Pekka Eero Peljo, Romain Bourdon

Photo-ionic cells are a simple and scalable concept for direct solar energy storage, where the redox fuels produced by the photoreaction are separated in different phases to prevent recombination. The presence of chaotropic agents such as urea, that break ...

Amer Chemical Soc2015

Evidence from in Situ X-ray Absorption Spectroscopy for the Involvement of Terminal Disulfide in the Reduction of Protons by an Amorphous Molybdenum Sulfide Electrocatalyst

Xile Hu, Heron Vrubel, Daniel Andreas Merki

The reduction of protons into dihydrogen is important because of its potential use in a wide range of energy applications. The preparation of efficient and cheap catalysts for this reaction is one of the issues that need to be tackled to allow the widespre ...

American Chemical Society2015

Hydrogen evolution from a copper(I) oxide photocathode coated with an amorphous molybdenum sulphide catalyst

Michael Graetzel, Xile Hu, Heron Vrubel, Stanley David Tilley, Carlos Gilberto Morales Guio

Concerns over climate change resulting from accumulation of anthropogenic carbon dioxide in the atmosphere and the uncertainty in the amount of recoverable fossil fuel reserves are driving forces for the development of renewable, carbon-neutral energy tech ...

Nature Publishing Group2014

Photo-Ionic Cells: Two Solutions to Store Solar Energy and Generate Electricity on Demand

Hubert Girault, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Micheal Diarmaid Scanlon, Pekka Eero Peljo

A solar energy conversion concept based on the photo-induced separation of a pair of redox species in a biphasic liquid cell is presented. The redox pair is subsequently discharged in an electrochemical flow cell to generate electricity. To illustrate this ...

Amer Chemical Soc2014

Easily-prepared dinickel phosphide (Ni2P) nanoparticles as an efficient and robust electrocatalyst for hydrogen evolution

Michaël Bensimon, Xile Hu, Heron Vrubel, Ligang Feng

Polydispersed dinickel phosphide (Ni2P) nanoparticles were synthesized by a simple and scalable solid-state reaction. These nanoparticles are an excellent and robust catalyst for the electrochemical hydrogen evolution reaction, operating in both acidic and ...

Royal Society of Chemistry2014

Gold Metal Liquid-Like Droplets

Pierre-François Marie Brevet, Hubert Girault, Manuel Alejandro Méndez Agudelo, Heron Vrubel, Dmitry Momotenko, Micheal Diarmaid Scanlon, Evgeny Smirnov

Simple methods to self-assemble coatings and films encompassing nanoparticles are highly desirable in many practical scenarios, yet scarcely any examples of simple, robust approaches to coat macroscopic droplets with continuous, thick (multilayer), reflect ...

Amer Chemical Soc2014

Renewable hydrogen generation from a dual-circuit redox flow battery

Christos Comninellis, Hubert Girault, Xile Hu, Véronique Amstutz, Heron Vrubel, Kathryn Ellen Toghill, Francis Powlesland

Redox flow batteries (RFBs) are particularly well suited for storing the intermittent excess supply of renewable electricity; so-called “junk” electricity. Conventional RFBs are charged and discharged electrochemically, with electricity stored as chemical ...

Royal Soc Chemistry2014

Electrochemical reduction of CO2 in organic solvents catalyzed by MoO2

Xile Hu, Heron Vrubel, Sébastien Guidoux, Yeonji Oh

MoO2 microparticles act as an active catalyst for the electrochemical reduction of CO2 in organic solvents such as acetonitrile and dimethylformamide. The catalytic activity and product selectivity depend on temperature and water content of the solvent. ...

Royal Society of Chemistry2014