Publications by Juan Kiwi | EPFL Graph Search

TiO2/rough surface of woven cotton fabrics prepared by spin coating for antibacterial and self-cleaning processes

TiO2 has been widely used in developing self-cleaning coatings on textiles. Spin coating is widely used to prepare films due to its simplicity and the ability to control the thickness and the characteristics of the deposited layers. However, it has been sp ...

2025

Stable Ta2O5 nanotubes decorated by PbS by the SILAR method for photocatalytic dye degradation

Juan Kiwi, Sami Rtimi

Tantalum oxide Ta2O5 nanotubes (NTs) were prepared by electrochemical anodization and were decorated with lead sulfide nanoparticles PbS (NPs) by Successive Ionic Layer Adsorption and Reaction commonly known as the SILAR method. The PbS NPs/Ta2O5 NTs were ...

2023

TiO2/spacer succinate films grafted onto nylon as a new approach to develop self-cleaning textile fibers that remove stains: a promising way to reduce reliance on cleaning water

Juan Kiwi, César Pulgarin

Succinic acid was used as a spacer to bind titanium dioxide onto nylon as a new approach to develop self-cleaning fibers. Photoinduced decomposition of stains was achieved within acceptable times under ultraviolet A irradiation, a component of both solar l ...

SPRINGER2022

Photo-induced environmental remediation, biomedical imaging, and microbial inactivation by Mn-doped semiconductors: critical issues

Juan Kiwi, Sami Rtimi

The Mn-doping/decoration of S-containing semiconductor quantum dots (QDs) determine their photochemical properties and are important in the field of artificial photosynthesis. The Mn-mediated charge-transfer kinetics and energetics in composites of the typ ...

ELSEVIER SCI LTD2021

Update on Interfacial Charge Transfer (IFTC) Processes on Films Inactivating Viruses/Bacteria under Visible Light: Mechanistic Considerations and Critical Issues

Juan Kiwi, Sami Rtimi

This review presents an update describing binary and ternary semiconductors involving interfacial charge transfer (IFCT) in composites made up by TiO2, CuO, Ag2O and Fe2O3 used in microbial disinfection (bacteria and viruses). The disinfection mechanism, k ...

2021

Insight into the interaction of magnetic photocatalysts with the incoming light accelerating bacterial inactivation and environmental cleaning

Juan Kiwi, Sami Rtimi

This report presents an up-to-date review on the interaction of light with magnetic semiconductors during photocatalysis leading to bacterial inactivation and pollutant degradation. The acceleration in the photocatalytic reactions mediated by wide-band gap ...

ELSEVIER2021

Recent advances on sputtered films with Cu in ppm concentrations leading to an acceleration of the bacterial inactivation

Juan Kiwi, Sami Rtimi

This review focuses on the acceleration of the bactericidal and fungicidal effects by uniform, adhesive Cu-based nanocomposites on textile and thin polymer surfaces. The acceleration of the bacterial inactivation kinetics mediated by Cu, TiO2/Cu and ZrO2-T ...

ELSEVIER2020

New Evidence for Ag-Sputtered Materials Inactivating Bacteria by Surface Contact without the Release of Ag Ions: End of a Long Controversy?

Juan Kiwi, Sami Rtimi

The study provides new evidence for Ag-coated polyester (PES) mediating Escherichia colt inactivation by way of genetically engineered E. coli (without porins, from now denoted porinless bacteria). This allows the quantification of the bactericidal kinetic ...

AMER CHEMICAL SOC2020

Insights into the Photocatalytic Bacterial Inactivation by Flower-Like Bi2WO6 under Solar or Visible Light, Through in Situ Monitoring and Determination of Reactive Oxygen Species (ROS)

Juan Kiwi, César Pulgarin, Sami Rtimi, Stefanos Giannakis, Minoo Karbasi

This study addresses the visible light-induced bacterial inactivation kinetics over a Bi2WO6 synthesized catalyst. The systematic investigation was undertaken with Bi2WO6 prepared by the complexation of Bi with acetic acid (carboxylate) leading to a flower ...

2020

Evidence for a dual mechanism in the TiO2/CuxO photocatalyst during the degradation of sulfamethazine under solar or visible light: Critical issues

Juan Kiwi, César Pulgarin, Sami Rtimi, Jiajie Yu

This study presents the photocatalytic degradation of sulfamethazine (SMT) on TiO2/CuxO nanotubes (NTs) by a differentiated mechanism under low intensity solar light and indoor visible light irradiation. In the presence of TiO2/CuxO nanotubes, the SMT-degr ...

ELSEVIER SCIENCE SA2019

Advances in catalytic/photocatalytic bacterial inactivation by nano Ag and Cu coated surfaces and medical devices

Juan Kiwi, Sami Rtimi

The design, synthesis, fundamentals and evaluation of 2D/3D antimicrobial surfaces are addressed in detail in the current review. Recent advances in the antimicrobial mechanism, kinetics and properties of Ag, Cu and Ag-Cu surfaces in the dark and under lig ...

ELSEVIER SCIENCE BV2019

Flower-like magnetized photocatalysts accelerating an emerging pollutant removal under indoor visible light and related phenomena

Juan Kiwi, César Pulgarin, Sami Rtimi, Minoo Karbasi

This study presents the first evidence for FeOx intra-gap states on Bi2WO6- magnetized materials enhancing the Norfloxacin (NFX) degradation with respect to Bi2WO6 within acceptable times under indoor visible light (< 5 mW/cm(2)). The kinetically faster ph ...

ELSEVIER SCIENCE SA2019

Monitoring the energy of the metal ion-content plasma-assisted deposition and its implication for bacterial inactivation

Juan Kiwi, Sami Rtimi

Cu-polyester (Cu-PES) was sputtered by high power impulse magnetron sputtering (HIPIMS) and by low energy direct current magnetron sputtering (DCMS). The total amount and distribution of the Ar+, Cu+ and Cu2+ ions were determined as well as the bacterial i ...

ELSEVIER SCIENCE BV2019

Quantification of the local magnetized nanotube domains accelerating the photocatalytic removal of the emerging pollutant tetracycline

Juan Kiwi, Henrik Moodysson Rønnow, Ivica Zivkovic, Sami Rtimi, Jiajie Yu

( )Evidence is presented for the enhanced photodegradation of tetracycline (TC) by AgxO/FeOx/ZnO nanotubes (NTs) compared to AgxO/ZnO nanotubes under low-intensity solar light irradiation. A higher amount of the local magnetic domains with random orientati ...

ELSEVIER SCIENCE BV2019

Duality in the Mechanism of Hexagonal ZnO/CuxO Nanowires Inducing Sulfamethazine Degradation under Solar or Visible Light

Juan Kiwi, César Pulgarin, Sami Rtimi, Jiajie Yu

This study presents the first evidence for the photocatalytic performance of ZnO/CuxO hexagonal nanowires leading to sulfamethazine (SMT) degradation. The chemical composition of the nanowires was determined by X-ray fluorescence (XRF). The sample with the ...

2019

Femtosecond Spectroscopy of Au Hot-Electron Injection into TiO2: Evidence for Au/TiO(2 )Plasmon Photocatalysis by Bactericidal Au Ions and Related Phenomena

Juan Kiwi, Sami Rtimi

In the present work, we provide evidence for visible light irradiation of the Au/TiO2 nanoparticles' surface plasmon resonance band (SPR) leading to electron injection from the Au nanoparticles to the conduction band of TiO2. The Au/TiO2 SPR band is shown ...

2019

Mechanisms of the Antibacterial Effects of TiO2-FeOx under Solar or Visible Light: Schottky Barriers versus Surface Plasmon Resonance

Juan Kiwi, Sami Rtimi

This study reports the significant mechanistic difference between binary-oxide antibacterial films with the same composition but different microstructures. Binary TiO2-FeOx films were found to present a faster bacterial inactivation kinetics under visible ...

MDPI2018

Exploring the role of post-translational modifications in regulating α-synuclein interactions by studying the effects of phosphorylation on nanobody binding

Juan Kiwi, Bruno Claude Daniel Fauvet, Hilal Lashuel, Anass Chiki, Farah El Turk

Intracellular deposits of α-synuclein in the form of Lewy bodies are major hallmarks of Parkinson’s disease (PD) and a range of related neurodegenerative disorders. Post-translational modifications (PTMs) of α-synuclein are increasingly thought to be major ...

2018

New evidence for disinfection, self-cleaning and pollutant degradation mediated by GF-TiO2-Cu mats under solar/visible light in mild oxidative conditions

Michaël Bensimon, Juan Kiwi, César Pulgarin, Laura Victoria Suárez Murillo, Stefanos Giannakis

This study presents the performance of GF-mats loaded with TiO2 and Cu under solar/visible light leading to bacterial inactivation and pollutant degradation at both solid-air and solid-liquid interfaces. The GF-mats show effective water disinfection, self- ...

Elsevier2017

Synchronic coupling of Cu2O(p)/CuO(n) semiconductors leading to Norfloxacin degradation under visible light: Kinetics, mechanism and film surface properties

Michaël Bensimon, Juan Kiwi, César Pulgarin, Sami Rtimi, Gcina Mamba

The study presents the first evidence for Norfoxacin photodegradation by uniform, adhesive and robust CuOx-polystyrene (CuOx-PES) films under visible light. Repetitive Norfloxacin degradation was attained on CuOx-PES films activated by visible light. The s ...

Elsevier2017