Publications by Endre Horvath | EPFL Graph Search

Tuning the color of high-karat gold in Au-TiO2 nanoparticle composites all the way to black

László Forró, Andrzej Sienkiewicz, Claudio Grimaldi, Endre Horvath

For centuries, artisans have harnessed gold nanoparticles to imbue their creations with the vibrant hues that captivate the eye through interactions with visible light. In modern times, these distinct optoelectronic characteristics have pivoted toward the ...

Cell Press2024

Perovskite-based detector for reactor dosimetry monitoring

László Forró, Endre Horvath, Pavel Frajtag, Andreas Pautz, Péter Szirmai, Márton Kollár

Hybrid halide perovskites have demonstrated significant efficiency in detecting a broad spectrum of high-energy radiation, including X-rays, gamma rays (γ-rays), and neutrons. Given the common occurrence of mixed radiation fields, we investigated the perfo ...

EDP Sciences2024

Effect of the Deposition of Vanadium-Oxide on the Photocatalytic Activity of TiO2 Nanotubes and Its Photodiode Performance Interfaced with CH3NH3PbI3 Single Crystal

László Forró, Endre Horvath, Pavao Roko Andricevic

In this study, we report the influence of vanadium oxide (VO), as a photosensitive component, on the photoactivity of TiO2 nanotubes (TNTs). A series of TNTs of varying tube diameter were synthesized by the anodization of titanium foils at different voltag ...

MDPI2023

Solar water purification with photocatalytic nanocomposite filter based on TiO2 nanowires and carbon nanotubes

Luca Rossi, László Forró, Dominique Grandjean, Andrzej Sienkiewicz, Florian Frédéric Vincent Breider, Endre Horvath, Miriam Gaál

Water contamination due to environmental conditions and poor waste management in certain areas of the world represents a serious problem in accessing clean and safe drinking water. This problem is especially critical in electricity-poor regions, where adva ...

2022

High-pressure investigations in CH3NH3PbX3 (X = I, Br, and Cl): Suppression of ion migration and stabilization of low-temperature structure

László Forró, Endre Horvath, Márton Kollár

Hybrid organic-inorganic halide perovskites represent a promising next-generation photovoltaic material with drawbacks for structure stability and composition concerns. Demonstrations of ion migration and molecular dynamics suggest room for structural cont ...

AMER PHYSICAL SOC2022

Fast Lead-Free Humidity Sensor Based on Hybrid Halide Perovskite

Dragan Damjanovic, László Forró, Alla Arakcheeva, Endre Horvath, Pavao Roko Andricevic, Márton Kollár, Trpimir Ivsic

An environmentally friendly analog of the prominent methylammonium lead halide perovskite, methylammonium bismuth bromide (MA3Bi2Br9), was prepared and investigated in the form of powder, single crystals and nanowires. Complete characterization via synchro ...

2022

“Forbidden” Polarisation and Extraordinary Piezoelectric Effect in Organometallic Lead Halide Perovskites

Dragan Damjanovic, László Forró, Endre Horvath, Márton Kollár, Lukas Riemer

Organometallic lead halide perovskites are highly efficient materials for solar cells and other optoelectronic applications due to their high quantum efficiency and exceptional semiconducting properties. A peculiarity of these perovskites is the substantia ...

2022

Ultrasensitive 3D Aerosol-Jet-Printed Perovskite X-ray Photodetector

László Forró, Alla Arakcheeva, Bálint Náfrádi, Endre Horvath, Pavao Roko Andricevic, Anastasiia Glushkova, Márton Kollár

X-ray photon detection is important for a wide range of applications. The highest demand, however, comes from medical imaging, which requires cost-effective, high-resolution detectors operating at low-photon flux, therefore stimulating the search for novel ...

2021

Highly flexible CH3NH3PbI3 micro- and nanowires

Luca Rossi, László Forró, Raphaël Foschia, Luka Ciric, Massimo Spina, Endre Horvath, Márton Kollár

CH3NH3PbI3 is known to be very efficient in photon to electron conversion, which makes it extremely popular in opto-electronic applications ranging from solar cells to photodetectors. The material is very brittle in bulk, single crystalline, and thin film ...

AIP Publishing2021

Fighting Health Hazards in Lead Halide Perovskite Optoelectronic Devices with Transparent Phosphate Salts

László Forró, Endre Horvath, Xavier François Mettan, Pavao Roko Andricevic, Márton Kollár

Organic-inorganic lead halide perovskite (CH3NH3PbI3) solar cells have surpassed 25% power conversion efficiency, being ready for industrial-scale production of cheap photovoltaic (PV) panels. In this action, the major hurdle is its lead content, which in ...

AMER CHEMICAL SOC2021

Hybrid halide perovskite neutron detectors

László Forró, Andrzej Sienkiewicz, Bálint Náfrádi, Endre Horvath, Pavel Frajtag, Andreas Pautz, Pavao Roko Andricevic, Márton Kollár

Interest in fast and easy detection of high-energy radiation (x-, gamma-rays and neutrons) is closely related to numerous practical applications ranging from biomedicine and industry to homeland security issues. In this regard, crystals of hybrid halide pe ...

Nature Portfolio2021

Infrared and 2-Dimensional Correlation Spectroscopy Study of the Effect of CH3NH3PbI3 and CH3NH3SnI3 Photovoltaic Perovskites on Eukaryotic Cells

László Forró, Endre Horvath, Ryma Iness Benmessaoud

We studied the effect of the exposure of human A549 and SH-SY5Y cell lines to aqueous solutions of organic/inorganic halide perovskites CH3NH3PbI3 (MAPbI3) and CH3NH3SnI3 (MASnI3) at the molecular level by using Fourier transform infrared microspectroscopy ...

2020

Mechanical response of layered titanate nanowires

Luca Rossi, László Forró, Raphaël Foschia, Endre Horvath, Anastasiia Glushkova

The mechanical response of individual titanate nanowires (H2Ti3O7), synthesized in an upscaled production (kg/month) was investigated by means of an Atomic Force Microscope (AFM) in nanomechanical spectroscopic mode. Because of their layered structure, bes ...

2020

Tuning ferromagnetism at room temperature by visible light

László Forró, Bálint Náfrádi, Massimo Spina, Endre Horvath, Xavier François Mettan, Andrea Pisoni, Péter Szirmai

Most digital information today is encoded in the magnetization of ferromagnetic domains. The demand for ever-increasing storage space fuels continuous research for energy-efficient manipulation of magnetism at smaller and smaller length scales. Writing a b ...

National Academy of Sciences2020

Light-induced charge transfer at the CH3NH3PbI3/TiO2 interface-a low-temperature photo-electron paramagnetic resonance assay

Philippe Bugnon, László Forró, Andrzej Sienkiewicz, Bálint Náfrádi, Endre Horvath, Péter Szirmai, Pavao Roko Andricevic, Anastasiia Glushkova, Márton Kollár, Konstantins Mantulnikovs

The performance of organic-inorganic metal halide perovskites-based (MHPs) photovoltaic devices critically depends on the design and material properties of the interface between the light-harvesting MHP layer and the electron transport layer (ETL). Therefo ...

2020

Thermal coarsening of individual titanate nanowires and their assemblies: Surface vs. bulk diffusion

Luca Rossi, László Forró, Xavier Berdat, Massimo Spina, Endre Horvath, Laurent Syavoch Bernard, Sergiy Katrych

The thermal coarsening of titanate nanowires was investigated from room temperature to 1000 degrees C by AFM, SEM, XRD and Raman spectroscopy. Phase transformation kinetics and the external morphology were studied in two configurations: i) as individual an ...

2020

Photocatalytic Nanowires-Based Air Filter: Towards Reusable Protective Masks

László Forró, Andrzej Sienkiewicz, Endre Horvath, Caroline Lehmann

In the last couple decades, several viral outbreaks resulting in epidemics and pandemics with thousands of human causalities have been witnessed. The current Covid-19 outbreak represents an unprecedented crisis. In stopping the virus' spread, it is fundame ...

WILEY-V C H VERLAG GMBH2020

Kilogram-Scale Crystallogenesis of Halide Perovskites for Gamma-Rays Dose Rate Measurements

László Forró, Andrzej Sienkiewicz, Bálint Náfrádi, Endre Horvath, Pavel Frajtag, Andreas Pautz, Vincent Pierre Lamirand, Pavao Roko Andricevic, Márton Kollár

Gamma-rays (gamma-rays), wherever present, e.g., in medicine, nuclear environment, or homeland security, due to their strong impact on biological matter, should be closely monitored. There is a need for simple, sensitive gamma-ray detectors at affordable p ...

2020

Mahan excitons in room-temperature methylammonium lead bromide perovskites

László Forró, Majed Chergui, Ana Akrap, Endre Horvath, Tania Palmieri, Edoardo Baldini, Márton Kollár

In a seminal paper, Mahan predicted that excitonic bound states can still exist in a semiconductor at electron-hole densities above the insulator-to-metal Mott transition. However, no clear evidence for this exotic quasiparticle, dubbed Mahan exciton, exis ...

Nature Publishing Group2020

Radiation detection and energy conversion in nuclear reactor environments by hybrid photovoltaic perovskites

László Forró, Andrzej Sienkiewicz, Bálint Náfrádi, Endre Horvath, Pavao Roko Andricevic, Márton Kollár

Detection and direct power conversion of high energy and high intensity ionizing radiation could be a key element in next generation nuclear reactor safety systems and space-born devices. For example, the Fukushima catastrophe in 2011 could have been large ...

Elsevier2020