Cursos de verano 2026

29/06-03/07: Cursos de Verano @ University de Santander Cyrille was invited to give a course about self-assembly. It took place in Suances, an amazing place on the coast. This event was organized by Leonardo Scarabelli and Marta Sanz (top and bottom row on the right)

Deciphering nanoparticle self-assembly in drying levitated droplets

Figure: a) Schematic illustration of the setup to monitor EISA in levitated droplets. b) images of the shrinking droplet (top) and the corresponding 2D SAXS patterns (bottom) acquired at two different times, close to the beginning and the end of the process.

15/06/2026 How do nanoparticles organize as a liquid droplet dries? A new study uncovers the key role of surfactants in directing the formation of ordered plasmonic materials. Evaporation-induced self-assembly (EISA) is a widely used strategy to transform dilute nanoparticle (NP) suspensions into highly ordered materials. However, despite its importance for nanoscience and materials engineering, the microscopic mechanisms governing this process remain incompletely understood, especially for anisotropic NPs dispersed in water. In a recent study, researchers [1] have shed new light on this question by investigating the drying dynamics of silver nanorods in the presence of a prevalent surfactant, cetyltrimethylammonium chloride (CTAC). Using an innovative experimental approach based on levitated droplets, the team was able to monitor in real time and without contact the structural evolution of NPs throughout the evaporation process. Their findings challenge a widely accepted view of EISA: while it is generally assumed that the progressive increase in concentration during drying drives the formation of ordered structures, the study demonstrates that the initial surfactant concentration is in fact the key parameter controlling the emergence of NP superlattices. This effect outweighs the influence of NP concentration and even of the particle shape. The researchers show that surfactant micelles play a dual and dynamic role: at early stages they act as depletants, inducing attractive interactions that trigger the nucleation and growth of ordered assemblies of nanorods. At later stages, as their concentration increases, these same micelles undergo a phase transition toward a gel-like state, which freezes the NPs assembly process. By combining time-resolved small-angle X-ray scattering with complementary electron microscopy and microbeam analyses, the team also reveals that ordering occurs before complete drying and extends across the entire droplet, leading to a radial organization of the nanorods at the mesoscale. These results provide practical guidelines for designing reproducible nanoparticle superlattices and open new perspectives for the fabrication of plasmonic metamaterials, photonic structures, and functional nanodevices. [1], le Laboratoire de Physique des Solides (CNRS/Université de Paris-Saclay), SWING beamline (SOLEIL Synchrotron, l'Institut Charles Sadron (CNRS/Université de Strasbourg) et le CIC Nanogune (Donostia San Sebastian, Espagne). DOI: 10.1021/acs.nanolett.6c01619

Matrix pic-nic 2026

08-06-2026 We held the MATRIX team’s annual picnic, featuring bread, cheese, and wine, along with other nice things.

Welcome Sergio!

01/04/2026 Sergio Triviño obtained his Bachelor’s Degree in Chemistry from the Complutense University of Madrid (2017–2021). He then earned his Master’s Degree in Chemical Science and Technology from the same institution (2021–2022), where his research focused on the irradiation of gold nanoparticles with ultrashort laser pulses. In October 2023, Sergio began his PhD under the supervision of Dr. Guillermo González Rubio in the Crystal Lab group at the Complutense University of Madrid. His current doctoral research focuses on the synthesis of multi-metallic nanocrystals, with the aim of developing advanced nanomaterials for catalytic applications.

SOLEIL

04/02/2026 Just a picture of the group going to the SWING beamline

Welcome Lan!

Dao Phuong Lan earned her Engineering Degree in Chemistry from Hanoi University of Science and Technology, where she specialized in pharmaceutical chemistry.  She then shifted her academic focus toward physical chemistry and materials science by joining the Erasmus Mundus SERP+ Master’s Program at Université Paris-Saclay, supported by the IDEX Paris-Saclay scholarship. During her M1 internship at ICMMO, she worked on materials science research involving the fabrication and physicochemical characterization of TiO₂ thin films.  Currently, she is completing her M2 internship on the project “Dynamic Stabilization in Light-Responsive Colloidal Assemblies” under the supervision of Prof. Cyrille Hamon and Prof. Marianne Impéror-Clerc, where she explores light-controlled colloidal self-assembly using photoswitchable surfactants to dynamically and reversibly tune interparticle interactions, enabling the formation of reconfigurable nanostructures with tailored optical and plasmonic responses. Her research interests lie at the intersection of chemistry and nanomaterials, particularly focusing on plasmonics, light-driven self-assembly, photochemistry, and the design of adaptive, out-of-equilibrium colloidal metamaterials with tunable structural and optical properties.

Congratulation to Dr Marcone!

24/11/2025 Jules defended his thesis this week and became a Dr. of the University Paris-Saclay after 2h15 of intense discussion with the jury. The jury was composed of:  >  Caroline Salzemann (MONARIS, Sorbonne Université) >  Glenna Drisko (Laboratoire de Chimie, ENS Lyon) >  Guillaume Viau (LPCNO, INSA Toulouse) >  Tobias Kraus (Universität des Saarlandes) >  Fabienne Testard (CEA Saclay) >  Rachel MEALLET (ISMO, Université Paris-Saclay)

Welcome Noemi!

03/11/2025 Noemi Ghelardini obtained her Bachelor’s Degree in Chemistry from the University of Florence (2019–2022), where she worked on the development of molecularly imprinted polymers for the detection of TNF-alpha, using Surface Plasmon Resonance (SPR) as the analytical technique. She then earned her Master’s Degree in Inorganic Nanochemistry from the University of Pavia (2023–2025), focusing on the synthesis of silver nanoparticles and palladium nanocubes. As part of her training, she completed an Erasmus traineeship in the “In Situ Nanochemistry” group led by Dr. Scarabelli at the University of Cantabria, where she gained hands-on experience in soft lithography, self-assembly, nanoimprint lithography, and hot embossing techniques. In November 2025, Noemi began her PhD under the supervision of Dr. Cyrille Hamon and Dr. Marianne Impéror-Clerc in the MATRIX group at the Laboratoire de Physique des Solides (LPS), focusing on the synthesis and self-assembly of noble metal nanorods, with the aim of exploring and controlling polymorphism in multicomponent systems.

Colloidal Tunable Metasurfaces via Depletion-Induced Self-Assembly of Plasmonic Nanorods

03/11/2025 Self-assembly offers a scalable approach to creating nanostructures with tunable properties, particularly for plasmonic materials. Conventional self-assembly often produces dense 3D supercrystals, which restrict light and analyte accessibility. By contrast, directing assembly into 2D metasurfaces increases active surface area and promotes collective optical responses, making them highly promising for sensing and photocatalysis. While metasurfaces are typically immobilized on interfaces, here we introduce the concept of “colloidal metasurfaces”, which are liquid-dispersed and reconfigurable assemblies. Specifically, we exploit depletion-induced self-assembly (DISA) to reversibly organize anisotropic plasmonic nanorods (Au@Ag) into colloidal metasurfaces. By tuning the depletion strength, we achieve dimensional control between 2D and 3D arrangements and modulate the compacity of the colloidal assemblies from 21% to 80%. Assemblies of nanorods with different cross sections reveal shape-dependent reconfigurability: pentagonal rods maintain hexagonal lattice symmetry, whereas square rods undergo symmetry shifts from rhombic to square. These colloidal metasurfaces support multiple assembly–disassembly cycles without loss of optical function and enable modulation of Raman scattering through lattice parameter tuning. Together, this work establishes a functional, reconfigurable colloidal platform for plasmonic metasurfaces using shape-directed DISA. https://doi.org/10.1021/acsami.5c17436

Faceted 3D Supercrystals for Plasmonic Photocatalysis: Design, Reactivity, and Operando Studies

13/10/2025 Solar-driven plasmonic photocatalysis has emerged as a powerful tool to enhance chemical reactivity, improving the efficiency and selectivity in a large number of transformations. Plasmonic nanoparticles are often implemented in photocatalysis as colloidal dispersions but they face issues related to the reduced photoactivation ofthe metallic surface in concentrated solutions and poor longterm colloidal stability. To overcome these limitations, 3D plasmonic supercrystals (SCs) created through the depletion- and evaporation-induced self-assembly of metal nanoparticles as novel heterogeneous plasmonic photocatalysts are introduced. They present large electromagnetic field enhancements associated to the formation of regular arrays of plasmonic hot spots, leading to improved chemical reactivities through the generation of hot charge carriers. To demonstrate this, two challenging organic transformations are chosen, an oxidative polymerization and different C─C cross-coupling reactions, that can be activated by modifying the chemical composition of the assemblies. The anisotropic shapes ofthe building blocks lead to the formation of3D SCs exposing different surfaces. Importantly, by performing operando surface-enhanced Raman spectroscopy at the single SC level, the surface-dependent reactivity ofeach individual plasmonic superstructure is unveiled. The combined experimental and theoretical approach provides with key insights into structure-function correlations and offers guidelines for the rational design of versatile SC photocatalysts. This work has been led by Charlène Brissaud and Miguel Comesana Hermo @ ITODYS (Univ. Paris-Cité). DOI: https://doi.org/10.1002/sstr.202500481

Strong and Weak Coupling Nanophysics with Free Electron Beams

29/09/2025, new review article The work of Luis M. Liz-Marzán, his colleagues, and other nanochemists has been essential in the emergence of electron spectroscopies for nano-optics applications. After a brief presentation of these techniques and their applications to individual plasmonic nanoparticles, this paper focuses on a short review of the study of the coupling between optical excitations at the nanometer scale, made possible by recent advances in electron spectroscopies. In particular, plasmon–plasmon, plasmon–exciton, and plasmon–phonon couplings are reviewed. Thanks to Mathieu Kociak and the STEM group for having us! https://doi.org/10.1002/adom.202501548

Plasmonic NPs Synthesis by colloidal chemistry

Selection of TEM images of Au or Au@Ag NPs with various morphology obtained in the team. The colors distinct series of nanocrystal: gold bipyramids of different size (purple), Au@Ag nanorods of varying shell thickness (red), Au@Ag bipyramids of varying shell length (green).

Shaping nanomaterials

Construction of nanoscale devices is a crucial step toward the sucess of nanotechnologies in a variety of fields. Although construction by addition of individual building blocks might appear impossible without using nanomachines, it can actually be carried out by simply exploiting the different magnitude of attractive and repulsive interaction forces at the nanoscale. For example, gravity is negligible for nanoparticles, but other forces become dominant and require the nanoparticles to be coated with selected molecules. Thus, one can simply let the solvent evaporate and wait the nanoparticles to organize into ordered structures without any intervention. Such strategy is one of the core of the concept of self-assembly.

Gold and silver nanoparticles

Plasmonic nanoparticles (Au and Ag) have been object of fascination since ancient time for the preparation of stained glass. Such elementary building block are extremly robust and their use in monuments stand the test of time. A not too far example from the laboratory is the "Sainte-Chapelle du Palais" at "l'île de la cité" in Paris (see image, wikipédia). This phenomenon, commonly witnessed by everyone, originates from the plasmonic properties of metallic nanoparticles. 

Optical properties of nanoparticles

The strong optical properties of nanoparticles (e.g. plasmonic or semiconducting) can be tuned across the visible to the mid infra-red range by modifying their size and shape. When such nanoparticles are organized in ensembles, collective properties are obtained that differ from those of individual particles and the resulting optical properties can be further tuned and even amplified. In particular, plasmon coupling in small gaps (1–10 nm) between plasmonic nanoparticles results in intense electric fields (i.e.,hot-spots) that can be exploited for many purposes, such as sensing, biomaterials, metamaterials design, switching devices, and so forth.

Use of light to study nanoparticles self assembly

We use UV/Vis spectrometry and X-ray scattering tecniques (SAXS) to study nanoparticles super-structures. The structural study of the material is the first step before understanding its overall properties and considering applications. SAXS is an experimental technique used to study the structural properties of materials and gives information on the size and orientation of the nanoparticles, their arrangement, the characteristic interdistances and the possible long-range organization. In a scattering experiment, ordered phases give diffraction signals that are called Bragg peaks. Analysis of such signals requires adapting standard methods of crystallography to the nanoscale, as the relevant length scale is much larger than the atomic scale. UV/Vis spectrometry is used complementary to measure the collective optical properties. Both techniques can be used in situ to study self assembly's pathways. 

Mesoporous materials

A mesoporous material is a material containing pores with diameters between 2 and 50 nm. We are devising materials containing a mesoporous architecture to enhance size and shape selectivity for guest molecules or to template nanoparticles synthesis. 

Alumni

Jules Marcone (PhD)

Jules Marcone graduated in 2022 from the Paris-Saclay University in 2022 with a Magister of Molecular Physicochemistry, focusing on Inorganic, Physical, and Materials Chemistry. During his study, he developed various skills in characterization methods (SAXS, XRD, SEM, etc.), and also in nanoparticle synthesis and self-assembly.   Jules started his PhD in October 2022 under the supervision of Marianne Impéror-Clerc and Cyrille Hamon at the LPS, on the synthesis and self-assembly of nanoparticles focusing particularly on cobalt nanorods, aiming for collective magnetic properties. He defended in december 2025 and is now working as a post-doc at BC materials (Bilbao, Spain).

Sébastien Marchand (M2) 2025

I graduated in 2023 from a double bachelor’s degree in Physics and Chemistry, at Université Paris Cité. Following this, I pursued a master’s degree in Chemistry, specializing in Chemistry for Energy and Nanosciences. During my studies, I learned various skills in nanoparticle synthesis and characterization. Thus in 2025, I joined the Matrix team at the LPS for my M2 internship where I am investigating the growth of colloidal crystals through microfluidic channels and studying the kinetics of their self-assembly. My internship is supervised by Dr. Cyrille Hamon, Dr. Marianne Impéror-Clerc and Jaime Gabriel Trazo. He is now doing a PhD at ITODYS (Université Paris-Cité)

Claire Hotton (post-doc) 2022-2025

Claire Hotton obtained her PhD from Sorbonne University under the supervision of Natalie Malikova in PHENIX laboratory. She worked on the structure and properties of hydrogels based on ionene-type cationic polyelectrolytes and clay nanoplatelets. She is now joining the Laboratoire of Physique des Solides as a postdoctoral researcher with Cyrille Hamon and Erwan Paineau. Currently, her interest focuses on the self-assembly of colloidal liquid crystals by acoustic levitation.   Claire is now doing post-doc at FAST (University Paris-Saclay) and CEA Saclay.

Rahul Nag (post-doc) - 2023-2024

Rahul Nag obtained his PhD from IIT Bombay under the supervision of Chebrolu Pulla Rao in Bio-Inorganic Chemistry Laboratory. He worked on the surface functionalization of nanostructures by organic conjugates specially calixarenes which involved applications in sensing, cancer cell killing, catalysis. He did a one-year post-doctoral research in CBMN/University of Bordeaux under the supervision of Emilie Pouget in the Chiral Molecular Assemblies Group led by Reiko Oda. He is joined the Laboratoire of Physique des Solides as a postdoctoral researcher with Cyrille Hamon. Currently, his interest focuses on the synthesis of gold nanostructures controlling their shapes and sizes for possible application in non-linear optics. He is now doing a postdoc at ITODYS (Université Paris-Cité)

Wajdi Chaâbani (post-doc) - 2020-2022

Wajdi Chaâbani obtained his Ph.D. from the University of Technology of Troyes (France) and the University of Sciences of Sfax (Sfax, Tunisie) under the supervisions of Jérôme Plain and of Abdallah Chehaidar in July 2019. He was a postdoctoral researcher in IEMN Laboratory (Lille, France) from September 2019 to August 2020. He then joined the Laboratoire de Physique des Solides in Orsay (France) as postdoctoral researcher. Currently, his interest focuses on self-assembling plasmonic nanoparticles in confinement. The nanostructuration will be resolved at the single supercrystal level using an innovative Small Angle X-ray Scattering (SAXS) setup developed on a synchrotron beamline.(SWING, @SOLEIL). He is now doing a postdoc at ITODYS (Université Paris-Cité)

Jianan Qian (M2) - 2022

I obtained my Bachelor of Engineering in Nano Materials and Technology from Soochow University in China. During my undergraduate study, I worked on several projects related to nanoscaled functional materials for energy conversion and storage under the supervision of Prof. Yanguang Li.   I am now the M2 student from Erasmus Mundus Joint Master program: SERP+. Currently, I am working on my thesis project about self-assembly of colloidal liquid crystal in levitation under the supervision of Dr. Cyrille Hamon and Dr. Erwan Paineau.

Jieli Lyu (PhD) - 2018-2022

Jieli Lyu completed her M.S. degree at the Key Laboratory of Applied Surface and Colloid Chemistry of Shaanxi Normal University. She studied under the supervision of Prof. Junxia Peng and Prof. Yu Fang, and her main research topics were (1) synthesis and characterization of amphiliphic compounds; (2) formulation and performances of the emulsions; (3) emulsion-templated preparation of porous materials and their catalytic performance. She started her PhD in october 2018. Her research interest focuses on nanomaterials with a multiscale organization as well as shedding light on the self-assemblies pathways using light scattering techniques.  Jieli have now a position at Xi'an University of Technology (China)

Samantha Roque (M2) - 2021

Samantha Roque earned her Bachelor of Science in Chemistry (2017) and in Materials Science Engineering (2018) from Ateneo de Manila University in the Philippines. She worked on printable carbon composites and biosilica inks for perovskite solar cells under Erwin P. Enriquez, Ph.D.    She is now doing her master's degree under the Erasmus Mundus Joint Master Degree SERP+. She is at present doing her internship on Anisotropic plasmonic-semiconductor nanocomposites for photocatalytic applications which is a joint project between the “Institut de Chimie Physique” and the “Laboratoire de Physique des Solides” supervised by Cyrille Hamon Ph.D. and ‪Mohamed Nawfal Ghazzal, Ph.D.     She is now doing a PhD at Université du Sud Toulon Var

  Masa Johar (M1)- 2021

Masa Johar graduated from An-Najah National University, Palestine (2020),  with a bachelor's degree in Applied Chemistry. She joined University of Paris Saclay in September  2020 to start her master's degree within the Chemistry International Track program for two years.   Currently, she is doing her M1 internship on "Colloidal chemistry of plasmonic triangular nanoplatelets" under supervision of Prof. Cyrille Hamon at the Laboratory of Solid Physics (LPS). Her main motivation is to find the best protocol for synthesizing triangular gold nanoparticles.      Finally, she is looking forward to being a highly skilled researcher enthusiastic about supporting advancements in the nanotechnology world, passionate about increasing knowledge to drive growth and needed improvements related to sustainable developments in Energy, Health and Environment.   She is now doing a PhD at Université Paris Saclay

 Kinanti Aliyah (M2)- 2019

Sergio Triviño

Sergio Triviño obtained his Bachelor’s Degree in Chemistry from the Complutense University of Madrid (2017–2021). He then earned his Master’s Degree in Chemical Science and Technology from the same institution (2021–2022), where his research focused on the irradiation of gold nanoparticles with ultrashort laser pulses. In October 2023, Sergio began his PhD under the supervision of Dr. Guillermo González Rubio in the Crystal Lab group at the Complutense University of Madrid. His current doctoral research focuses on the synthesis of multi-metallic nanocrystals, with the aim of developing advanced nanomaterials for catalytic applications.

Phuong Lan Dao

Dao Phuong Lan earned her Engineering Degree in Chemistry from Hanoi University of Science and Technology, where she specialized in pharmaceutical chemistry. She then shifted her academic focus toward physical chemistry and materials science by joining the Erasmus Mundus SERP+ Master’s Program at Université Paris-Saclay, supported by the IDEX Paris-Saclay scholarship. During her M1 internship at ICMMO, she worked on materials science research involving the fabrication and physicochemical characterization of TiO₂ thin films. Currently, she is completing her M2 internship on the project “Dynamic Stabilization in Light-Responsive Colloidal Assemblies” under the supervision of Prof. Cyrille Hamon and Prof. Marianne Impéror-Clerc, where she explores light-controlled colloidal self-assembly using photoswitchable surfactants to dynamically and reversibly tune interparticle interactions, enabling the formation of reconfigurable nanostructures with tailored optical and plasmonic responses. Her research interests lie at the intersection of chemistry and nanomaterials, particularly focusing on plasmonics, light-driven self-assembly, photochemistry, and the design of adaptive, out-of-equilibrium colloidal metamaterials with tunable structural and optical properties.

Noemi Ghelardini

Noemi Ghelardini obtained her Bachelor’s Degree in Chemistry from the University of Florence (2019–2022), where she worked on the development of molecularly imprinted polymers for the detection of TNF-alpha, using Surface Plasmon Resonance (SPR) as the analytical technique. She then earned her Master’s Degree in Inorganic Nanochemistry from the University of Pavia (2023–2025), focusing on the synthesis of silver nanoparticles and palladium nanocubes. As part of her training, she completed an Erasmus traineeship in the “In Situ Nanochemistry” group led by Dr. Scarabelli at the University of Cantabria, where she gained hands-on experience in soft lithography, self-assembly, nanoimprint lithography, and hot embossing techniques. In November 2025, Noemi began her PhD under the supervision of Dr. Cyrille Hamon and Dr. Marianne Impéror-Clerc in the MATRIX group at the Laboratoire de Physique des Solides (LPS), focusing on the synthesis and self-assembly of noble metal nanorods, with the aim of exploring and controlling polymorphism in multicomponent systems.

Nika Kutalia

I started thinking about chemistry when I participated in international chemistry Olympiad, (ICHO) 48 where I became fascinated about science. Therefore, I studied chemistry at San Diego State University Georgia and obtained bachelor’s degree there. Then, I decided to divert study direction towards physical chemistry and materials science that is why I applied to SERP master program. Currently, I am involved in M2 internship in LPS where I work for the project “Templated Colloidal Crystals with Collective Optical or Magnetic Properties” which is supervised by Dr.Cyrille Hamon and Dr.Marianne Imperor-Clerc.   Currently, I am particularly interested in self-assembly of nanoparticles and how to utilize the properties of nanoparticles in the field of plasmonics/photonics and imaging.

Jaime Gabriel Trazo

Jaime Gabriel Trazo earned his bachelor degrees in Chemistry and in Materials Science and Engineering at the Ateneo de Manila University (2019, 2020), where he worked on formulating green silver nanoparticle inks for printed electronics and on nanocellulose synthesis, under Dr. Jose Mario Diaz and Dr. Erwin Enriquez. He was also a National Awardee at the BPI-DOST Science Awards 2019 in the Philippines.   He then pursued his master’s degree under the Erasmus Mundus SERP+ Program. For his M2 internship, he joined the Laboratoire de Physique des Solides, where he works on the self-assembly of nanoparticles into supercrystals with collective optical/magnetic properties, under Dr. Cyrille Hamon and Dr. Marianne Impéror-Clerc. He obtained a grant from the ED2-MIB doctoral school to continue the adventure at LPS in PhD.

Marianne Impéror-Clerc

Marianne Impéror-Clerc has a permanent position at CNRS as ‘directrice de recherche’. She studied Physics at the ENS de Saint-Cloud (1986-1990) where she passed the ‘aggrégation de Physiques’ (1989) before obtaining her PhD (1992) and HdR ‘Habilitation à diriger des recherches’ (2007) at the Université Paris-Sud in Orsay. Her research is devoted to structural studies of self-assembled systems and her favorite experimental tool is Small Angle Scattering using X-rays or neutrons (SAXS and SANS).  For example, for mesoporous materials, the control of the architecture of the porosity allows to optimize transport properties. Main goal is to control the nanostructure during the synthesis of such materials. For this, time-resolved scattering experiments allow to follow in real time the formation of the materials and to elucidate the mechanisms involved. Her research thus lies at the frontier between Soft Matter and Materials Chemistry. She is alos regularly involved in activities about Crystallography for education and the general public (http://www.cristallo2014.u-psud.fr/)

Team MATRIX

Cyrille Hamon

Cyrille Hamon obtained his Ph.D. from the University of Rennes 1 (France) under the supervision of Pascale Even-Hernandez and Valérie Marchi in 2013. He was a postdoctoral fellow in Luis Liz-Marzán laboratory (CIC Biomagune, Spain) from 2014 to 2016. He then joined the laboratories of Gaëlle Charron and Pascal Hersen (MSC, Université Paris 7) from 2016 to 2017. He has been appointed in 2017 with a permanent CNRS position in the Laboratoire de Physique des Solides in Orsay. His current interest focuses on devising new plasmonic architectures for sensing applications.