Samuel Marre

• PhD - HDR
• Senior Researcher - Head of the Supercritical Fluids Group at CNRS - Bordeaux University

The turbulent mixing of two miscible fluids is investigated in a high pressure (HP) coflow microreactor operated at 100 bar. Ethanol and CO2 are selected as model solvents to mimic the final targeted application, i.e.: a supercritical antisolvent process at microscale (μSAS). We first demonstrate experimentally that turbulent mixing can be reached...

In this perspective article, we emphasize the combination of Surface-Enhanced Raman Spectroscopy (SERS) and Microfluidic devices. SERS approaches have been widely studied and used for multiple applications including trace molecules detection, in situ analysis of biological samples and monitoring or, all of them with good results, however still with...

Submicronization of organic compounds is a challenging requirement for applications in the imaging and pharmaceutical fields. A new Supercritical Anti-Solvent process with microreactor (µSAS) was developed for nanoparticle (NP) synthesis. Tetrahydrofuran (THF) was used to solubilize a model organic molecule, tetraphenylethylene, and supercritical c...

In this review, we present a general overview of the current progress in pore scale experimentations related to CO2 geological storage. In such processes occurring in porous media, most of the phenomena start from (bio)geochemical reactions and transport mechanisms at the pore scale. Therefore, in order to predict the overall consequences of CO2 in...

In this review, selected examples are presented to demonstrate how microfluidic approaches can be utilized for investigating microbial life from deep geological environments, both from practical and fundamental perspectives. Beginning with the definition of the deep underground biosphere and the conventional experimental techniques employed for the...

We present a new extended parametric equation-of-state model for thermodynamic properties and the correlation length for a simple fluid near its liquid–gas critical point. The model involves 16 universal parameters to perfectly match 10 leading universal amplitudes of the asymptotic Ising-like limit of the critical-to-classical crossover functions...

Combating global warming-related climate change demands prompt actions to reduce greenhouse gas emissions, particularly carbon dioxide. Biomass-based biofuels represent a promising alternative fossil energy source. To convert biomass into energy, numerous conversion processes are performed at high pressure and temperature conditions, and the design...

In this study, X-ray laminography is used to monitor the evolution of a model 3D packed bed porous medium on a chip (micromodels) undergoing reactive flows. The obtained 3D images are used to compute the fluid flow patterns and develop insights into dissolution mechanisms. This study is a first proof of concept study, with controlled micromodels, a...

Here, we demonstrate the continuous synthesis of gallium nitride (GaN) nanophotocatalysts exhibiting high quantum confinement using a preheated supercritical millireactor. The GaN quantum dots (QDs) are obtained from the direct thermolysis of a single source amido complex precursor (tris(dimethyl)amido gallium(III) dimer), in anhydrous supercritica...

Vaterite, a polymorphic form of precipitated calcium carbonate, is an interesting material for various applications such as formulation of drug delivery systems due to its nanoporous structure. One of the carbonation processes to obtain nanostructured microspheres of vaterite consists in mixing an aqueous calcium phase with a supercritical CO2 phas...

Here, we present a novel methodology based on high-pressure microfluidics to rapidly perform temperature-based phenotyping of microbial strains from deep-sea environments. The main advantage concerns the multiple on-chip temperature conditions that can be achieved in a single experiment at pressures representative of the deep-sea, overcoming the co...

High-pressure microfluidic systems exhibit favorable capacity to enhance mixing quality compared to conventional macroscale liquid systems. These mixing conditions are very interesting for the preparation of fluorescent organic nanoparticles by supercritical antisolvent process. In this work, fundamental mechanisms of microfluidic supercritical ant...

Supercritical Carbon Dioxide treatment of clean and soiled Filtering Face-Piece respirators is shown to meet mandatory requirements for safe reuse of FFP2. Preliminary tests enabled us to select optimal conditions for Supercritical Carbon Dioxide treatment of FFP2, for one hour at 343 K under 7.5 MPa, with a biocide solution. FFP2s from Paul Boyé®...

A chemistry platform for the fast continuous synthesis of III–V quantum dots is demonstrated. III‐nitride QDs are prepared by using short residence times (less than 30 s) in a one‐step continuous process with supercritical solvents. GaN QDs prepared via this route exhibit strong UV photoluminescence with a structuring of the emission signal at low...

We present in here a simple and low cost continuous segmented-flow process for the synthesis of Ag and Au spherical-shaped nanoparticles. Different residence times (RT) were used to perform the nanoparticle synthesis, observing that at low RT, the Ag nanoparticles production, which uses a fast reduction reaction with NaBH <sub xmlns:mml="http://www...

We describe a method for the fabrication of acoustic metasurfaces, which is based on soft porous polymer materials. The materials are obtained using an emulsion templating technique, which allows for the fabrication of soft porous polymers with fully controlled porosity values between 0 and 30%. Our approach involves the polymerization of water-in-...

A simple and easy way is proposed for the fabrication of a highly attenuating composite material for underwater acoustics. The approach involves the introduction of porous polymer beads into a polyurethane matrix. The porous beads are prepared through an emulsion-templating approach, and two different processes are used. The first one uses microflu...

Switchable materials are increasingly considered for implementation in devices or multifunctional composites leading to a strong need in terms of reliable synthetic productions of well‐defined objects. Here, an innovative and robust template‐free continuous process was developed to synthesize nanoparticles of a switchable coordination polymer, incl...

A series of microgravity investigations have been formulated to be performed in the DECLIC and DECLIC-Evo on board the International Space Station to provide a better understanding of fundamental processes that take place in water solutions at near-critical conditions. These investigations rely on the design heritage of an earlier fundamental physi...

The Forum for Sustainability through Life Cycle Innovation (FSLCI), the Fraunhofer Institute for Environmental, Safety, and Energy Technology UMSICHT and the Université de Bordeaux organized a joint workshop on the subject of "Linking the Life Cycle Inventory and Impact Assessment of Marine Litter and Plastic Emissions" on 18th March 2020. The work...

High pressure/high temperature microreactors based on silicon-Pyrex® microfabrication technologies have attracted increasing interest for various applications providing optical access in high pressure flow processes. However, they cannot be coupled to infrared spectroscopy due to the limited optical transparency (up to ~2.7 μm in the infrared regio...

In this study, the hydrodynamic behavior of coflowing fluids CO 2 and ethanol has been investigated in a high-pressure microfluidic reactor working at supercritical conditions, in which the two fluids are completely miscible. The velocity field has been measured by Micro Particle Image Velocimetry (μPIV) for different temperatures between 20 and 50...

A variety of core‐shell CdSe‐CdS nanorods or quantum rods (QRs), both sphere (CdSe) in rod (CdS) and rod (CdSe) in rod (CdS) have been synthesized in a seeded‐growth approach using a very efficient and highly thermally stable steroidal cadmium precursor replacing the more common CdO: cadmium deoxycholate. The core‐shell QRs display very high photol...

Photocatalysis is a green technology which converts abundantly available photonic energy into useful chemical energy. With a rapid rise of flow photoreactors in the last decade, the design and development of novel semiconductor photocatalysts is happening at a blistering rate. Currently, developed synthetic approaches have allowed the design of div...

Thermophysical properties of fluid systems are highly desirable as they are used in many industrial processes both from a chemical engineering point of view and to push forward the development of modeling approaches. To access these data, microfluidic approaches have recently attracted increasing interest as they provide flexible and reliable ways...

Microfluidics have been used extensively for the study of flows of immiscible fluids, with a specific focus on the effects of interfacial forces on flow behavior. In comparison, inertia-driven flow of confined coflowing fluids has received scant attention at the microscale, despite the fact that the effects of microscale confinement are expected to...

Microfluidics have been used extensively for study of flows of immiscible fluids, with specific focus on the effects of interfacial forces on flow behavior. In comparison, inertia-driven flow of confined coflowing fluids has received scant attention at the microscale, despite the fact that the effects of microscale confinement are expected to influ...

To understand the boiling crisis mechanism, one can take advantage of the slowing down of boiling at high pressures, in the close vicinity of the liquid-vapor critical point of the given fluid. To preserve conventional bubble geometry, such experiments need to be carried out in low gravity. We report here two kinds of saturated boiling experiments....

Analyses of ground-based experiments on near-critical fluids to precisely determine their density can be hampered by several effects, especially the density stratification of the sample, the liquid wetting behavior at the cell walls, and a possible singular curvature of the “rectilinear” diameter of the density coexisting curve. For the latter effe...

In the modern theory of critical phenomena, the liquid-vapor density diameter in simple fluids is generally expected to deviate from a rectilinear law approaching the critical point. However, by performing precise scannerlike optical measurements of the position of the SF6 liquid-vapor meniscus, in an approach much closer to criticality in temperat...

This chapter describes one area of applications where supercritical CO2 (scCO2) is effectively used as a solvent. CO2-based solvents can be used to perform physical or chemical transformations, the two main routes introduced in this chapter to prepare advanced materials. For processes based on physical transformations, CO2 can be used as a solvent,...

This publication concerns the design of advanced nanostructured inorganic materials using supercritical fluids. A brief overview of the different experimental and numerical tools, which are now available for the scientific community and engineers, is proposed giving access to a better understanding but also a better control on material synthesis. T...

Instant one-pot synthesis of functional layered double hydroxides (LDHs) is demonstrated for the first time using a continuous hydrothermal multi-step process. The as-prepared pristine material displays high crystallinity and very small LDH nanoparticle size, lateral dimensions below 100 nm and a thickness below 20 nm, all being achieved in only 5...

Solid sorbents based on metal oxides have been investigated as an alternative to liquid sorbents for CO2 capture. Amongst them, acid-base properties of cerium oxide make it an excellent candidate for such applications at rather low temperature. In order to assess the suitability of this material, we quantified CO2 adsorption/desorption capacities a...

Single Quantum Rod Orientation Mapping of CdSe-CdS in Soft Nano-Materials; the highly emissive core-shell CdSe-CdS QRs are used to image and study the underlying non-emissive nanostructure

This paper reports the carbon dioxide detection in silicon-Pyrex high pressure microfluidic devices mimicking geological conditions encountered in deep saline aquifers using an in situ infrared optical sensor. The middle infrared source inserted inside the microchannel is based on infrared emission from Dy³⁺ sulfide glass fibers. The broad emission...

Correction for ‘Combining microfluidics and FT-IR spectroscopy: towards spatially resolved information on chemical processes' by Adeline Perro et al., React. Chem. Eng., 2016, DOI: 10.1039/c6re00127k.

The development of nanosciences and nanotechnologies in the 21th century is linked to the progresses made with the nanomaterials preparation methods. Control, reproducibility, scalability and sustainability are the key issues for the design of advanced nanostructured materials. Among the synthesis approaches, the supercritical fluids based flow pro...

Based on a single non-universal temperature scaling factor present in a simple fluid case, a detailed analysis of non-universal parameters involved in different critical-to-classical crossover models is given. For the infinite limit of the cutoff wave number, a set of three scaling-parameters is defined for each model such that it shows all the sha...

This review outlines the combination of infrared spectroscopy and continuous microfluidic processes. FTIR spectroscopy gives access to the microscopic chemical composition of samples, which can be correlated with their macroscopic properties. This approach is widely used in chemistry or biology to get insights into reactive media. Meanwhile, the mi...

A non-analytical scaling determination of the Ising-like crossover parameter is proposed considering the critical isochore of a simple fluid at finite distance from its critical temperature. The mean crossover functions, estimated from the bounded results of the massive renormalization scheme in field theory applied to the \(\left( \Phi ^{2}\right)...

In order to investigate at pore scale the mechanisms involved during CO2 injection in a water saturated pore network, a series of displacement experiments is reported using high pressure micromodels (Geological Labs on Chip – GloCs) working in real geological conditions (25 < T (°C) < 75 and 4.5 < p (MPa) < 8). The experiments were focused on the i...

GaN quantum dots (QDs) are prepared in a one-step continuous process using anhydrous solvents at supercritical conditions (and temperatures below 450 °C) in short residence times, typically less than 25 s. The as-prepared QDs exhibit a strong luminescence in the ultraviolet (λmax ~ 350 nm) in agreement with the synthesis of quantum-confined GaN nan...

The development of nanosciences and nanotechnologies in the twentyfirst century is linked to the progresses made with the nanomaterial synthesis approaches. Control, reproducibility, scalability, and sustainability are the key issues for the design of advanced nanostructured materials. Among the synthesis methods, the supercritical fluid-based flow...

In this work, the solvent effect on the synthesis of CeO2 nanocrystals synthesized in near- and supercritical alcohols is discussed. The materials prepared displayed a unique morphology of small nanocrystals (<10 nm) aggregated into larger nanospheres (∼100-200 nm). In such syntheses, alcohol molecules directly interact with the nanocrystal surface...

The composite materials of two anisotropic nano-objects: CdSe-CdS nanorods and photoactive anthracene based supramolecular organogel are developed for their unique optical properties with widespread applications in optoelectronics, lasers, sensors and other smart materials. The first step involves developing high quality isotropic and anisotropic c...

By structuring the matter at the nano level using highly versatile nanotechnology approaches and apparatus, multi-functionalities with manifestation of enhanced and/or novel useful properties could be attained. The challenges in nanoengineering are the ability to tune the nano-object characteristics (size, distribution, composition, surface chemist...

CeO2 nanocrystals (NCs) have attracted increasing interest over the past few years, in particular for their use in catalysis reactions. Near- and supercritical alcohols mediated syntheses have been proved to be innovative ways to obtain CeO2 NCs with controlled crystallite sizes (from 3 to 8 nm depending on the alcohol) and surface functionalities,...

We demonstrate in here a powerful scalable technology to synthesize continuously high quality CdSe quantum dots (QDs) in supercritical hexane. Using a low cost, highly thermally stable Cd-precursor, cadmium deoxycholate, the continuous synthesis is performed in 400 μm ID stainless steel capillaries resulting in CdSe QDs having sharp full-width-at-h...

To understand the boiling crisis mechanism, one can take advantage of the slowing down of boiling at high pressures, in the close vicinity of the liquid-vapor critical point of the given fluid. To preserve conventional bubble geometry, such experiments need to be carried out in low gravity. We report here two kinds of saturated boiling experiments....

Near the critical point of fluids, critical opalescence results in light attenuation, or turbidity increase, that can be used to probe the universality of critical behavior. Turbidity measurements in ${\mathrm{SF}}_{6}$ under weightlessness conditions on board the International Space Station are performed to appraise such behavior in terms of both...

Synthesis of high quality nanocrystals of different shapes can be achieved through milifluidic techniques, e.g. capillaries with 500 micron internal diameters. One of the examples include CdSe QDs of different sizes emitting in the entire visible region (blue to red).

Dans le cadre du stockage géologique du CO2 , de nombreux phénomènes ayant lieu à l'échelle du pore sont mal appréhendés, le projet ANR CGSµLab, dans lequel s'inscrit mon travail, s'intéresse à la compréhension physico-chimique de ces phénomènes à partir d'expériences de micro-fluidique et de simulations numériques dans les conditions réelles de st...

A successful implementation of in situ X-ray scattering analysis of synthetized particle materials in silicon/glass microreactors is reported. Calcium carbonate (CaCO3) as a model material was precipitated inside the microchannels through the counter-injection of two aqueous solutions, containing carbonate ions and calcium ions, respectively. The s...

The last few years have seen the development of a new field of investigation, so called ”Supercritical Microfluidics” with the basic idea to combine the advantages of size reduction provided by microsystems - advanced control of operating parameters, reproducibility, in situ and online characterization, rapid screening, fast mass and heat transfer...

We report for the first time the use of a microfluidic supercritical antisolvent process (μSAS) to synthesize semiconducting polymer nanoparticles (NPs) of poly(3-hexylthiophene) (P3HT). Solvent-free P3HT NPs with average diameters as small as 36 ± 8 nm are obtained. They are continuously spray-coated on substrates to fabricate OFET devices, demons...

Under supercritical conditions (i.e. when the temperature and the pressure of a substance are above its thermodynamic critical point), water becomes a fluid with unique properties that can be used to treat a wide variety of wastes. For example, during Supercritical Water Oxidation (SCWO) organic wastes can be almost fully converted into carbon diox...

In this work, we present a novel microfluidic-based approach for investigating thermodynamics of multicomponents systems at high pressures and temperatures, such as determining miscibility diagrams and supercritical coordinates of complex mixtures. The developed method is primarily based on (i) the on chip bubbles and dew points detection through o...

The 3-15 μm range is a key region for a large number of applications in diverse areas such as biology and medicine, molecular spectroscopy, ground based and space borne environmental monitoring but also an important issue of instrumentation for astronomy and astrophysics to achieve complex but very reliable instruments. Going to the mid IR region i...

Understanding the environment and the biogeochemistry that occurs in the deep subsurface is of major importance in order to improve processes of geological resources exploitation (i.e. oil and gas fields, geothermal and water resources, mining). The microorganisms, namely bacteria and proteobacteria, are involved in both positive and negative effec...

The fast and controlled synthesis of surface modified cerium oxide nanoparticles was carried out in supercritical {ethanol + alcohol derivative} mixtures. The newly found ability of supercritical alcohols to graft onto cerium oxide nanocrystals (CeO2 NCs) during their synthesis was exploited to control their surface chemistry via the addition of th...

Processing strategies for the synthesis of hybrid materials stand as relevant ways to modulate the particle size and morphology. We present herein the use of a continuous high temperature–high pressure (HT–HP) process for the synthesis of a new cerium based metal–organic framework (MOF). The HT–HP harsh thermodynamic synthesis conditions lead to MO...

The turbidity ( \(\tau \) ) measurements of Güttinger and Cannell (Phys Rev A 24:3188-3201, 1981) in the temperature range \(28\,\text {mK}\le T-T_{c}\le 29\,\text {K}\) along the critical isochore of homogeneous xenon are reanalyzed. The singular behaviors of the isothermal compressibility ( \(\kappa _{T}\) ) and the correlation length ( \(\xi \)...

Cerium-oxide based nanostructures attract increasing interest for their use in multiple applications. In particular, the substitution of Ce atoms by other elements with lower oxidation state is used to control oxygen vacancies within the oxide structures, which can greatly enhance the material properties for catalysis applications. Among the synthe...

Supercritical water upgrading of heavy crude oils is a combined physical/chemical process involving chemical reaction, phase behavior, and mixing. Fundamental understanding of each of these major phenomena is lacking. The purpose of this study is to obtain experimental data on phase behavior and mixing for heavy oil model compounds and water near i...

The sustainable management of the CO2 industry is currently a key factor for preventing climate changes due to greenhouse effect. Among the proposed remediation solutions is the deep underground CO2 geological storage. Such storage required adequate scientific knowledge to prevent from unexpected events during injection or final storage. In this co...

The combination of highly active Pd nanocrystal (NC) types with tailored surface properties (various ligands) - e.g. organic-inorganic hybrid NCs - as catalysts opens avenues towards new synthetic pathways, implying a faster practical alternative for adjusting and screening the reaction conditions. Pd@dppf and Pd@PCy3 NCs have been successfully pre...

ZnO nanocrystals (NCs) are of increasing interest in many industrial applications especially in the field of optochemical sensors. We recently demonstrated the synthesis of excitonic luminescent ZnO NCs using the perfectly controlled environment offered by supercritical microfluidics. However, the limited production rates of such microscale synthes...