Publications by Pekka Eero Peljo

Ionosomes: Observation of Ionic Bilayer Water Clusters

Hubert Girault, Sunny Isaïe Maye, Pekka Eero Peljo, Evgeny Smirnov

Emulsification of immiscible two-phase fluids, i.e., one condensed phase dispersed homogeneously as tiny droplets in an outer continuous medium, plays a key role in medicine, food, chemical separations, cosmetics, fabrication of micro- and nanoparticles an ...

AMER CHEMICAL SOC2021

Vanadium‐manganese redox flow battery: Study of Mn(III) disproportionation in the presence of other metallic ions

Hubert Girault, Sunny Isaïe Maye, Pekka Eero Peljo, Danick Reynard, Solène Cindy Gentil, Vimanshu Chanda

The Mn(III)/Mn(II) redox couple with a standard potential of +1.51 V vs . SHE has drawn interest for the design of V/Mn redox flow battery (RFB). However, Mn(III) disproportionation leads to a loss of capacity, an increase of pressure drop and electrode pa ...

Wiley2020

Structure and reactivity of the polarised liquid–liquid interface: what we know and what we do not

Hubert Girault, Astrid Johana Olaya Avendano, Grégoire Clément Gschwend, Pekka Eero Peljo

Charge transfer phenomena at the interface between two immiscible electrolyte solutions (ITIES) are electrochemical reactions taking place in soft media. Owing to their liquid nature, the ITIES shows a large panel of electrochemical reactions including ele ...

2020

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

Solid electrochemical energy storage for aqueous redox flow batteries: The case of copper hexacyanoferrate

Hubert Girault, Grégoire Clément Gschwend, Pekka Eero Peljo, Danick Reynard, Evgeny Smirnov, Christopher Raymond Dennison, Elena Zanzola, Solène Cindy Gentil

All redox flow batteries suffer from low energy storage density in comparison with conventional Li-ion batteries. However, this issue can be mitigated by utilization of solid energy storage materials to enhance the energy storage capacity. In this paper we ...

2019

Electrochemical Dynamics of a Single Platinum Nanoparticle Collision Event for the Hydrogen Evolution Reaction

Haiqiang Deng, Pekka Eero Peljo

Chronoamperometry was used to study the dynamics of Pt nanoparticle (NP) collision with an inert ultramicroelectrode via electrocatalytic amplification (ECA) towards hydrogen evolution reaction. First, ECA and dynamic light scattering (DLS) results reveal ...

Wiley-VCH Verlag GmbH2018

Semi-analytical modelling of linear scan voltammetric responses for soluble-insoluble system: The case of metal deposition

Hubert Girault, Sunny Isaïe Maye, Pekka Eero Peljo, Imene Atek

The absence of general theoretical models describing linear sweep voltammetry (LSV) or cyclic voltammetry (CV) responses for soluble-insoluble systems such as one-step electrodeposition reactions under quasi-reversible condition makes it difficult to extra ...

2018

Gold Raspberry-Like Colloidosomes Prepared at the Water-Nitromethane Interface

Hubert Girault, Pekka Eero Peljo, Evgeny Smirnov

Here, we propose a simple shake-flask method to produce micron-size colloidosomes from a liquid-liquid interface functionalized with a gold nanoparticle film. A step-by-step extraction process of an organic phase partially miscible with water led to the fo ...

2018

Gold Nanofilms at Liquid–Liquid Interfaces: An Emerging Platform for Redox Electrocatalysis, Nanoplasmonic Sensors, and Electrovariable Optics

Thomas James Stockmann, Micheal Diarmaid Scanlon, Pekka Eero Peljo, Evgeny Smirnov

The functionality of liquid–liquid interfaces formed between two immiscible electrolyte solutions (ITIES) can be markedly enhanced by modification with supramolecular assemblies or solid nanomaterials. The focus of this Review is recent progress involving ...

2018

Simulations employing finite element method at liquid vertical bar liquid interfaces

Thomas James Stockmann, Micheal Diarmaid Scanlon, Pekka Eero Peljo

2018

Electrochemical potential window of battery electrolytes: the HOMO-LUMO misconception

Hubert Girault, Pekka Eero Peljo

A widespread misconception in the lithium ion battery literature is the equality of the energy difference of HOMO and LUMO of the solvent with the electrochemical stability window. HOMO and LUMO are concepts derived from approximated electronic structure t ...

2018

Effect of Chaotropes on the Transfer of Ions and Dyes across the Liquid–Liquid Interface

Hubert Girault, Grégoire Clément Gschwend, Pekka Eero Peljo, Evgeny Smirnov, Lucie Josette Renée Rivier, Elena Vladimirova

Chaotropes such as urea can break the structure of water, weakening the hydrophobic effect and reducing aggregation. Here, we investigated how the addition of urea affects the transfer of ions and cationic dyes across the interface between immiscible elect ...

2018

Solvent effect in photo-ionic cells

Hubert Girault, Pekka Eero Peljo, Elena Vladimirova

Photo-ionic cells convert solar energy into redox fuels. Unlike in photovoltaic devices where the photo-induced charge transfer reactions occur at an electrode, the photoreaction takes place in one bulk solution of a biphasic liquid-liquid system, and the ...

2018

Battery

Pekka Eero Peljo

In a battery system, an electrochemical cell has a first compartment containing a positive electrolyte with an electrode 2 at least partially immersed in the positive electrolyte containing the first redox active material, forming a positive half cell. A s ...

2017

Electrovariable gold nanoparticle films at liquid–liquid interfaces: from redox electrocatalysis to Marangoni-shutters

Hubert Girault, Grégoire Clément Gschwend, Pekka Eero Peljo, Evgeny Smirnov

Control over the physical properties of nanoparticle assemblies at a liquid–liquid interface is a key technological advancement to realize the dream of smart electrovariable nanosystems. Electrified interfaces, such as the interface between two immiscible ...

Royal Society of Chemistry2017

Understanding Digestive Ripening of Ligand-Stabilized, Charged Metal Nanoparticles

Hubert Girault, Pekka Eero Peljo

Most syntheses of thiolate-protected metal nanoparticles (NPs) include a thermochemical step in which the as-prepared, polydisperse NPs are transformed to a narrower size distribution in a poorly understood process known as digestive ripening (DR). Previou ...

American Chemical Society2017

Self-assembly and redox induced phase transfer of gold nanoparticles at the water-propylene carbonate interface

Hubert Girault, Pekka Eero Peljo, Evgeny Smirnov

Citrate-stabilized gold nanoparticles were found to spontaneously self-assemble into a lustrous film at a bare water–propylene carbonate interface after vigorous shaking, due to the extremely low interfacial tension. The presence of an electron donor, tetr ...

Royal Society of Chemistry2017

Photoproduction of Hydrogen by Decamethylruthenocene Combined with Electrochemical Recycling

Hubert Girault, Laurent Alexis Clément Vannay, Manuel Alejandro Méndez Agudelo, Grégoire Clément Gschwend, Micheal Diarmaid Scanlon, Pekka Eero Peljo, Lucie Josette Renée Rivier

The photoinduced hydrogen evolution reaction (HER) by decamethylruthenocene, Cp2RuII (Cp=C5Me5), is reported. The use of a metallocene to photoproduce hydrogen is presented as an alternative strategy to reduce protons without involving an additional phot ...

Wiley-Blackwell2017

Redox Electrocatalysis of Floating Nanoparticles: Determining Electrocatalytic Properties without the Influence of Solid Supports

Hubert Girault, Astrid Johana Olaya Avendano, Thomas James Stockmann, Micheal Diarmaid Scanlon, Pekka Eero Peljo, Evgeny Smirnov, Lucie Josette Renée Rivier

Redox electrocatalysis (catalysis of electron-transfer reactions by floating conductive particles) is discussed from the point-of-view of Fermi level equilibration, and an overall theoretical framework is given. Examples of redox electrocatalysis in soluti ...

2017

Variation of the Fermi level and the electrostatic force of a metallic nanoparticle upon colliding with an electrode (vol 8, pg 4795, 2017)

Hubert Girault, Pekka Eero Peljo

Royal Soc Chemistry2017