Publications associées à Silicon microresonator arrays: A comprehensive study on fabrication techniques and pH-controlled stress-induced variations in cantilever stiffness

Acids from fruits generate photoactive Fe-complexes, enhancing solar disinfection of water (SODIS): A systematic study of the novel " fruto-Fenton " process, effective over a wide pH range (4-9)

César Pulgarin, Aline Laetitia Schaub, Stefanos Giannakis, Giulio Farinelli, Mona Kohantorabi

This study aimed to enhance solar disinfection (SODIS) by the photo-Fenton process, operated at natural pH, through the re-utilization of fruit wastes. For this purpose, pure organic acids present in fruits and alimentary wastes were tested and compared wi ...

Pergamon-Elsevier Science Ltd2024

Photo-Fenton inactivation of MS2 bacteriophage at alkaline pH by Fe salts or nm to μm-sized oxides, and the Janus-faced effects of natural organic matter in surface waters

César Pulgarin, Stefanos Giannakis, Ogadimma Cassandra Oji-Okoro, Giulio Farinelli

In this study, MS2 bacteriophage was inactivated by homogeneous and heterogeneous photo-Fenton processes in an alkaline matrix (pH 8) using low concentrations of H2O2 and iron forms (1 mg/L), including Fe(II), Fe(III), and Fe (hydr)oxides. As a reference, ...

Elsevier2024

Additively manufactured stretchable zipping electrostatic actuators

Giulio Grasso

The use of soft and stretchable materials allows the development of adaptive robotic systems and human-machine interfaces that are more natural and comfortable to interact with. One of the application fields that benefits the most from these compliant mate ...

EPFL2024

Bacterial inactivation in sunlit surface waters is dominated by reactive species that emanate from the synergy between light, iron, and natural organic matter

César Pulgarin, Stefanos Giannakis, Jun Ma, Da Wang, Shuang Song

In this study, the synergistic and antagonistic effects of Fe species and coexisting natural organic matter (NOM) on the efficacy of solar light disinfection of water are investigated. Different initial iron species (Fe2+/Fe3+) and naturalorganic matter ty ...

Elsevier2023

Zinc hybrid sintering for printed transient sensors and wireless electronics

Danick Briand, Nicolas Francis Fumeaux

Transient electronics offer a promising solution for reducing electronic waste and for use in implantable bioelectronics, yet their fabrication remains challenging. We report on a scalable method that synergistically combines chemical and photonic mechanis ...

2023

Sunshine and a pinch of tropical soils: A natural, low-cost photo-Fenton variation for safer water, assisted by H2O2 or percabonate

Michaël Bensimon, César Pulgarin, Stefanos Giannakis, Jérémie Decker, Thomas Guillaume

Clean water is essential for human survival, but access to safe drinking water remains a challenge in resource -limited regions. Herein, we explored a low-cost but effective solution for water potabilization using natural iron sources from soils along with ...

ELSEVIER2023

Improving planar optode lifetime: encapsulation and optical release of pH-sensing optodes and assessment of their lifetime in situ

Victoria Alexandrine Julia Suzanne Marthe Fay

PurposePlanar fluorescent optodes are important tools for probing key parameters, such as the soil pH, O2 level, and CO2 level, associated with the biology and biochemistry process in the rhizosphere. In this paper, we address an important limitation of ex ...

SPRINGER HEIDELBERG2023

Effect of alkali, aluminium and equilibration time on calcium-silicate-hydrates

Yu Yan

Calcium silicate hydrate (C-S-H) is the main hydration product in Portland and blended cements, and greatly affects durability and mechanical properties of the hydrated cement. In the presence of Al-rich supplementary cementitious materials (SCMs), C-(A-)S ...

EPFL2022

Al uptake in calcium silicate hydrate and the effect of alkali hydroxide

Karen Scrivener, Yan Yan, Barbara Lothenbach

The effect of Al and of pH on the structure of calcium silicate hydrate (C-S-H), the most important hydration product in Portland and blended cement, was studied at Ca/Si similar to 1.0. The presence of Al led to higher amounts of secondary phases, larger ...

Pergamon-Elsevier Science Ltd2022

A new versatile hybrid MEMS technology for high sensitivity, fluid proof sensing applications

Matthias Neuenschwander

The field of micro electromechanical systems (MEMS) evolved from the microelectronic industry and the technologies developed to fabricate integrated circuits. As a result, MEMS are commonly fabricated on silicon wafers. The development of MEMS has been dri ...

EPFL2022

Visible-light driven water oxidation and oxygen production at soft interfaces

Hubert Girault, Astrid Johana Olaya Avendano, Jorge Gustavo Uranga, Julieta Soledad Riva, Sara Natalia Moya Betancourt

The visible light driven water oxidation reaction (WOR) by the organic electron acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-quinodimethane (TCNQF(4)) was studied at the water|butyronitrile interface. The WOR was performed at neutral pH, and without any ...

Royal Society of Chemistry2022

Configurable Organic Electrochemical Transistors with Printed Functional Materials for Multiplexed Sweat Analysis

Silvia Demuru

Monitoring human sweat with wearable biochemical sensors could give insights into the hydration, fatigue, and health status, tracking the variations of biomarkers non-invasively and in real-time. In this field, organic electrochemical transistors (OECTs) a ...

EPFL2022

Biostimulation as a sustainable solution for acid neutralization and uranium immobilization post acidic in-situ recovery

Pierre Rossi, Rizlan Bernier-Latmani, Thomas Coral

Major uranium (U) deposits worldwide are exploited by acid leaching, known as 'in-situ recovery' (ISR). ISR involves the injection of an acid fluid into ore-bearing aquifers and the pumping of the resulting metal-containing solution through cation exchange ...

2022

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

Effect of alkali hydroxide on calcium silicate hydrate (C-S-H)

Karen Scrivener, Barbara Lothenbach, Émilie Michèle L'Hôpital, Sheng-Yu Yang, Yu Yan

This paper investigates the effect of KOH and NaOH on C-S-H structure and solubility. Both KOH and NaOH have a similar effect, they increase pH values and silicon concentrations, and decrease calcium concentrations. At higher alkali hydroxide concentration ...

Pergamon-Elsevier Science Ltd2022

Water Orientation at the Anatase TiO2 Nanoparticle Interface: A Probe of Surface pKa Values

Arianna Marchioro, Marie Bischoff

The acid-base properties of surfaces significantly influence catalytic and (photo)electrochemical processes. Estimation of acid dissociation constants (pKa values) for colloids is commonly performed through electroanalytical techniques or spectroscopic met ...

AMER CHEMICAL SOC2022

Molecular insights into the electrical double layer of colloidal oxide particles obtained through second harmonic scattering

Marie Bischoff

Photocatalytic applications play an essential role in the search for alternative energy sources and environmental decontamination techniques. It is of fundamental interest to understand on a molecular level the aqueous solid/liquid interface, where photoca ...

EPFL2022

The effect of paste composition, aggregate mineralogy and temperature on the pore solution composition and the extent of ASR expansion

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri

The reaction kinetics of the alkali silica reaction depends on the composition of the pore solution. The evolution of the pore solution composition in different cement pastes and concretes was studied. Pastes containing silica fume or metakaolin had the lo ...

SPRINGER2022

Active sites on copper-based catalysts for electrochemical CO2 reduction selectively to C2+ products

Jie Zhang

Electrochemical CO2 reduction (eCO2RR) towards value-added chemicals, powered by renewable electricity, is a promising technology for storing the intermittent renewable energy in the form of chemical bonds. Among the various products of eCO2RR, multi-carbo ...

EPFL2022

Bulk Heterojunction Organic Semiconductor Photoanodes: Tuning Energy Levels to Optimize Electron Injection

Jun Ho Yum, Kevin Sivula, Nestor Guijarro Carratala, Arvindh Sekar, Liang Yao, Barbara Alexandra Primera Darwich, Yongpeng Liu, Han-Hee Cho, Juan Manuel Moreno Naranjo

The use of a bulk heterojunction of organic semiconductors to drive photoelectrochemical water splitting is an emerging trend; however, the optimum energy levels of the donor and acceptor have not been established for photoanode operation with respect to e ...

AMER CHEMICAL SOC2022