Nicolas Vogel

• PhD
• Professor (Associate) at Friedrich-Alexander-University Erlangen-Nürnberg

This study presents a comprehensive workflow for investigating particulate materials through combined 360{\deg} electron tomography (ET), nano-computed X-ray tomography (nanoCT), and micro-computed X-ray tomography (microCT), alongside a versatile sample preparation routine. The workflow enables the investigation of size, morphology, and pore syste...

Magic numbers in finite particle systems correspond to specific system sizes that allow configurations with low free energy, often exhibiting closed surface shells to maximize the number of nearest neighbors. Since their discovery in atomic nuclei, magic numbers have been essential for understanding the number-structure-property relationship in fin...

Structural coloration abounds in nature and its remarkable optical effects are mimicked in synthetic photonic crystals and glasses. However, the color saturation of these synthetic structures is often diminished by incoherent scattering caused by defects and irregularities. The inclusion of absorbing materials increases color saturation, but where...

Enzymatic degradation of polyethylene terephthalate (PET) represents a sustainable approach to reducing plastic waste and protecting fossil resources. The cost efficiency of enzymatic PET degradation processes could be substantially improved by reusing the enzymes. However, conventional immobilisation strategies, such as binding to porous carriers,...

Van der Waals materials and devices incorporating them exhibit highly thickness‐dependent properties. The small lateral dimensions of mechanically exfoliated 2D‐layered flakes, however, remarkably complicate their precise thickness determination. Quantitative analysis of reflectance measurements using optical microspectroscopy is proven to be as pr...

Liquid metal solutions are a new class of catalysts with outstanding properties in terms of catalytic conversion and resistance to coking. Finding the perfect combination of catalytic particles with homogeneous size distribution and support material able to stabilize them during catalysis is key for preparing model systems to gain understanding of...

The interfacial behavior of micro-/nanogels is governed to a large extent by the hydrophobicity of their polymeric network. Prevailing studies to examine this influence mostly rely on external stimuli like...

The efficient immobilization of GaPt liquid metal alloy droplets onto tailored supports improves catalytic performance by preventing coalescence and subsequent loss of active surface area. Herein, we use tailored supraparticle (SP) supports with controlled nanopores to systematically study the influence of pore sizes on the catalytic stability of G...

Ellipsoidal particles confined at liquid interfaces exhibit complex self-assembly behaviour due to quadrupolar capillary interactions induced by meniscus deformation. These interactions cause particles to attract each other in either tip-to-tip or side-to-side configurations. However, controlling their interfacial self-assembly is challenging becau...

Pickering emulsions (PEs) are stabilized by particles at the water/oil interface and exhibit superior long-term stability compared to emulsions with molecular surfactants. Among colloidal stabilizers, nano/microgels facilitate emulsification and can introduce stimuli responsiveness. While increasing their hydrophobicity is connected to phase invers...

Clusters of colloidal particles, often termed supraparticles, can provide more functionality than the individual particles they consist of. Since these functionalities are determined by the arrangement of the primary particles within a supraparticle, controlling the structure formation process is of fundamental importance. Here, we show how bucklin...

We report the synthesis of vertically aligned silicon nanowire (VA-SiNW) oligomer arrays coated with Au nanoparticle (NP) monolayers via a combination of colloidal lithography, metal-assisted chemical etching, and directed NP assembly. Arrays of SiNW monomers (i.e., isolated NWs), dimers, and tetramers are synthesized, decorated with AuNPs, and tes...

Microplastic particles have been discovered in virtually all ecosystems worldwide, yet they may only represent the surface of a much larger issue. Nanoplastics, with dimensions well below 1 µm, pose an even greater environmental concern. Due to their size, they can infiltrate and disrupt individual cells within organisms, potentially exacerbating e...

Inverse opal colorimetric sensors operating on wetting transitions usually rely on physical differences of the infiltrating liquid. Here, we exploit a reactive surface chemistry that changes wettability upon binding of...

Comprehending the interaction between light and material is crucial to the success of various laser-based processes, including laser powder bed fusion of polymers. The use of the promising near-infrared laser wavelength in laser powder bed fusion of polymers is limited by the necessity for absorption-enhancing (nano-) additives and insufficient kno...

Acoustic nanocavities (ANCs) with resonance frequencies much above 1 GHz are prospective to be exploited in sensors and quantum operating devices. Nowadays, acoustic nanocavities fabricated from van der Waals (vdW) nanolayers allow them to exhibit resonance frequencies of the breathing acoustic mode up to f ∼ 1 THz and quality factors up to Q ∼ 10³...

The narrow escape theory (NET) predicts the escape time distribution of Brownian particles confined to a domain with reflecting borders except for one small window. Applications include molecular activation events in cell biology and biophysics. Specifically, the mean first passage time τ¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepacka...

Metal‐organic frameworks (MOFs) are microporous adsorbents for high‐throughput gas separation. Such materials exhibit distinct adsorption characteristics owing to the flexibility of the crystal framework in a nanoparticle, which can be different from its bulk crystal. However, for practical applications, such particles need to be compacted into mac...

Bifurcations in kinetic pathways decide the evolution of a system. An example is crystallization, in which the thermodynamically stable polymorph may not form due to kinetic hindrance. Here, we use confined self-assembly to investigate the interplay of thermodynamics and kinetics in the crystallization pathways of finite clusters. We report the obs...

A geometrically tunable nanoporous system featuring enhanced active surface area by stacking of spheres in cylindrical pores is fabricated. Highly ordered arrays of straight, constricted pores are obtained by anodization of metallic aluminum. Polystyrene (PS) spheres are assembled inside the pores by flowing their suspension through the porous memb...

Liquid‐infused surfaces exhibit remarkable repellency properties toward water, oils, and complex fluids and are widely applied to maintain clean, operational, and high‐performing surfaces in various fields, from the biomedical sector to marine infrastructure. Polydopamine (PDA) forms an ideal base layer for the development of such coatings as it ad...

Supported catalytically active liquid metal solution (SCALMS) materials represent a recently developed class of heterogeneous catalysts, where the catalytic reaction takes place at the highly dynamic interface of supported liquid alloys. Ga nuggets were dispersed into nano-droplets in propan-2-ol using ultrasonication followed by the addition of Pt...

Porous materials are widely used in applications such as adsorption, catalysis and separation. The use of expander molecules is a versatile route to enlarge the mesopore size in micellar templated mesoporous silica materials. Typical expanders used for this purpose are fossil-based organic molecules such as trimethylbenzene (TMB). In the course of...

Molecular chirality plays fundamental roles in biology. The chiral response of a molecule occurs at a specific spectral position, determined by its molecular structure. This fingerprint can be transferred to other spectral regions via the interaction with localized surface plasmon resonances of gold nanoparticles. Here, we demonstrate that molecula...

Porous materials are widely used in applications such as adsorption, catalysis and separation. The use of expander molecules is a versatile route to enlarge the mesopore size in micellar templated mesoporous silica materials. Typical expanders used for this purpose are fossil-based organic molecules such as trimethylbenzene (TMB). In the course of...

Bifurcations in kinetic pathways decide the evolution of a system. An example is crystallization, in which the thermodynamically stable polymorph may not form due to kinetic hindrance. Here, we use confined self-assembly to investigate the interplay of thermodynamics and kinetics in the crystallization pathways of finite clusters. We report the obs...

Colloidal lithography utilizes self-assembled particle monolayers as lithographic masks to fabricate arrays of nanostructures by combination of directed evaporation and etching steps. This process provides complex nanostructures over macroscopic areas in a simple, convenient, and parallel fashion without requiring clean-room infrastructure and spec...

Colloidal crystals are excellent model systems to study self-assembly and structural coloration because their periodicities coincide with the wavelength range of visible light. Different assembly methods inherently introduce characteristic defects and irregularities, even with nearly monodisperse colloidal particles. Here, we investigate how these...

A drying droplet containing colloidal particles can consolidate into a spherical assembly called a supraparticle. Such supraparticles are inherently porous due to the spaces between the constituent primary particles. Here, the emergent, hierarchical porosity in spray‐dried supraparticles is tailored via three distinct strategies acting at different...

Hypothesis: The applicability of the dynamic light scattering method for the determination of particle diffusivity under confinement without applying refractive index matching was not adequately explored so far. The confinement effect on particle diffusion in a porous material which is relevant for particle chromatography has also not yet been ful...

Self-organisation is the spontaneous emergence of spatio-temporal structures and patterns from the interaction of smaller individual units. Examples are found across many scales in very different systems and scientific disciplines, from physics, materials science and robotics to biology, geophysics and astronomy. Recent research has highlighted how...

Photonic Colloidal Glass Continuous gradients in self‐assembled materials can provide functionality exceeding that of the homogenous case. In article number 2208745, Markus Retsch and co‐workers present a synthesis method that provides gradient size distributions via a controlled extraction emulsion process (CrEEP). The high degree of control allow...

Molecular chirality plays fundamental roles in biology. The chiral response of a molecule occurs at a specific spectral position, determined by its molecular structure. This fingerprint can be transferred to other spectral regions via the interaction with localized surface plasmon resonances (LSPRs) of gold nanoparticles. The arrangement of such na...

The narrow escape theory (NET) predicts the escape time distribution of Brownian particles confined to a domain with reflecting borders except for one small window. Applications include molecular activation events in cell biology and biophysics. Specifically, the mean first passage time can be analytically calculated from the size of the domain, th...

Colloidal crystals and glasses manipulate light propagation depending on their chemical composition, particle morphology, and mesoscopic structure. This light-matter interaction has been intensely investigated, but a knowledge gap remains for mesostructures comprising a continuous property gradient of the constituting particles. Here, a general syn...

Contamination of surfaces can cause loss of performance in a variety of applications. Bioinspired coatings based on the lotus or pitcher plants provide surface topographies that create superhydrophobic or slippery features with self‐cleaning properties. However, typical fabrication procedures often involve potentially toxic chemicals, perfluorinate...

Two‐dimensional colloidal crystallization provides a simple strategy to produce defined nanostructure arrays over macroscopic areas. Regularity and long‐range order of such crystals is essential to ensure functionality, but difficult to achieve in self‐assembling systems. Here, we introduce a simple loudspeaker setup for the acoustic crystallizatio...

The observable reaction rate of heterogeneously catalyzed reactions is known to be limited either by the intrinsic kinetics of the catalytic transformation or by the rate of pore and/or film diffusion. Here, we show that in gas generation reactions from liquid reactants, the nucleation of gas bubbles in the catalyst pore structure represents an add...

Low-cost and large-area chiral metamaterials (CMs) are highly desirable for practical applications in chiral biosensors, nanophotonic chiral emitters, and beyond. A promising fabrication method takes advantage of self-assembled colloidal particles, onto which metal patches with defined orientation are created using glancing angle deposition (GLAD)....

Hypothesis Polymer particles self-assembled into colloidal crystals have exciting applications in photonics, phononics, templates for nanolithography, and coatings. Cold soldering utilizing polymer plasticization by supercritical fluids enables a novel, low-cost, low-effort, chemical-free means for uniform mechanical strengthening of fragile polyme...

Optical microscale shear‐stress indicator particles are of interest for the in situ recording of localized forces, e.g., during 3D printing or smart skins in robotic applications. Recently developed particle systems are based on optical responses enabled by integrated organic dyes. They thus suffer from potential chemical instability and cross‐sens...

Biodegradable Polylactide Supraparticle Powders In article number 2205730, Nicolas Vogel and co‐workers show that composite supraparticles form powders of biodegradable polymers and nanoscale bioactive additives with tailored composition. These powders can be applied in the powder bed fusion process to fabricate functional biomaterials by additive...

The rational design and dispersion engineering of plasmonic colloid gratings are mainly responsible for advancing refractive index sensors. Herein, a 1D colloidal plasmonic lattice composed of nanoparticle dimer chains fabricated by a combination of interference lithography, soft molding, and colloidal self‐assembly is studied. The bottom‐up approa...

Many modern types of solar cells that rely exclusively on earth-abundant non-toxic materials include interfaces between a heavier metal chalcogenide and another type of semiconductor. Often, the chemical (adhesion) and physical (charge transfer) characteristics of those interfaces are the defining factors for the final device performance. Here, we...

How phonons propagate in nanostructures determines the flow of elastic and thermal energy in dielectric materials. However, a reliable theoretical prediction of the phonon dispersion relation requires experimental verification both near to and far from the Brillouin zone of the nanostructure. We report on the experimental hypersonic phonon dispersi...

Gold nanoparticle/silicon composites are canonical substrates for sensing applications because of their geometry-dependent physicochemical properties and high sensing activity via surface-enhanced Raman spectroscopy (SERS). The self-assembly of gold nanoparticles (AuNPs) synthesized via wet-chemistry on functionalized flat silicon (Si) and vertical...

Spherical particles confined to liquid interfaces generally self-assemble into hexagonal patterns. It was theoretically predicted by Jagla two decades ago that such particles interacting via a soft repulsive potential are able to form complex, anisotropic assembly phases. Depending on the shape and range of the potential, the predicted minimum ener...

Additive manufacturing, in particular powder bed‐based fabrication processes hold promise to revolutionize biomedical engineering for the ability to provide customized, functional implants, for example as bone replacement materials. However, providing functional powder particles that unify material requirements for biodegradable and bioactive bioma...

After spilling coffee, a tell-tale stain is left by the drying droplet. This universal phenomenon, known as the coffee ring effect, is observed independent of the dispersed material. However, for many technological processes such as coating techniques and ink-jet printing a uniform particle deposition is required and the coffee ring effect is a maj...

Self-organisation is the spontaneous emergence of spatio-temporal structures and patterns from the interaction of smaller individual units. Examples are found across many scales in very different systems and scientific disciplines, from physics, materials science and robotics to biology, geophysics and astronomy. Recent research has highlighted how...

The efficiency of a wet chemical route to synthesize gold nanostructures with tunable size and shape significantly depends on the applied solvent and the interaction of solvent molecules with other species such as gold ions. The ability of the organic solvent N-methyl-2-pyrrolidone (NMP) as a suitable medium for application in star-like gold nanost...

Supraparticles are spherical colloidal crystals prepared by confined self‐assembly processes. A particularly appealing property of these microscale structures is the structural color arising from interference of light with their building blocks. Here, we assemble supraparticles with high structural order that exhibit coloration from uniform, polyhe...

Single‐Core Double Emulsions The fabrication of single‐core double emulsions typically requires sophisticated microfluidic devices and meticulous operation protocols. In article number 2107338, Nicolas Vogel and co‐workers develop a convenient method to produce such tailored double emulsions with defined droplet structure using only vortex mixing....

Supraparticles are spherical colloidal crystals prepared by confined self‐assembly processes. A particularly appealing property of these microscale structures is their structural color arising from interference of light with their building blocks. Here, we assemble supraparticles with high structural order that exhibit coloration from uniform, poly...

Significance The spontaneous self-organization of matter is ubiquitous in nature and an attractive technological approach to create defined nanostructured materials from the bottom-up. Spherical colloidal particles are among the most widely used building blocks, but their self-assembly is limited to hexagonal symmetries as the densest sphere packin...

Double emulsions, such as water-in-oil-in-water droplets, are important material platforms for conducting fundamental research and technological applications. To date, well-defined double emulsion droplets consisting of a single water core and a thin oil shell can be exclusively formed with sophisticated microfluidic devices. The fabrication, prepa...

We present a photoanode concept for photoelectrochemical (PEC) water splitting based on metal nanoparticles (Au, Ag, Cu) deposited on a Ti mirror (NPoM) to photosensitize an intermediate TiO2 layer to induce the harvesting of light with sub-bandgap photon energies. The generation of hot electron-hole pairs in metallic nanostructures can occur eithe...

Colloidal supraparticles are micron-scale spherical assemblies of uniform primary particles, which exhibit emergent properties of a colloidal crystal, yet exist as a dispersible powder. A prerequisite to utilize these emergent functionalities is that the supraparticles maintain their mechanical integrity upon the mechanical impacts that are likely...

Defined surface functionalities can control the properties of a material. The layer-by-layer method is an experimentally simple yet very versatile method to coat a surface with nanoscale precision. The method is widely used to either control the chemical properties of the surface via the introduction of functional moieties bound to the polymer or c...

Imprint lithography has emerged as a reliable, reproducible, and rapid method for patterning colloidal nanostructures. As a promising alternative to top-down lithographic approaches, the fabrication of nanodevices has thus become effective and straightforward. In this study, a fusion of interference lithography (IL) and nanosphere imprint lithograp...

Polyhedral liquid marbles were fabricated using hydrophobic polymer plates in the shape of circle, heart and star as a stabilizer and water as an inner liquid phase. Boxes could be...

Bioinspired design takes blueprints from nature to replicate functionalities in man‐made materials. In article number 2100156, Salvatore Chiera, Carina Bittner, and Nicolas Vogel demonstrate a double bioinspiration approach that combines the slippery surface of the pitcher plant with the universal adhesion of mussel foot proteins. This strategy yie...

Chiral plasmonics is a fascinating research field that is attractive to scientists from diverse backgrounds. Physicists study light–matter interactions, chemists seek ways to analyze enantiomeric molecules, biologists study living objects, and material engineers focus on scalable production processes. Successful access to this emergent field for an...

Particulate materials with well-engineered properties are of key importance for many aspects in our daily life. Polymer powders with high flowability, for example, play a crucial role in the emerging field of powder-based additive manufacturing processes. However, the polymer- and composite material selection for these technologies is still limited...

Thermo-responsive microgel particles can exhibit a drastic volume shrinkage upon increasing the solvent temperature. Recently we found that the spreading of poly(N-isopropylacrylamide) (PNiPAm) microgels at a liquid interface under the influence of surface tension hinders the temperature-induced volume phase transition. In addition, we observed a h...

The combination of metal-assisted chemical etching (MACE) and colloidal lithography allows for the affordable, large-scale and high-throughput synthesis of silicon nanowire (SiNW) arrays. However, many geometric parameters of these arrays are coupled and cannot be addressed individually using colloidal lithography. Despite recent advancements towar...

Microgels exhibit a complex self-assembly behavior because of their ability to deform at a liquid interface or collapse upon compression. Here, we investigate the collective phase behavior of two-dimensional binary...

Self‐cleaning and repellent coatings ensure enduring performance of surfaces in many areas of technology and everyday life. An ideal repellent coating is efficient in removing contaminations, yet easy to apply on a wide range of surface materials. To devise such a coating, two bioinspirations are combined that show opposing interfacial properties:...

In article number 2100487, Ignacio Mínguez‐Bacho and co‐workers report the fabrication of highly ordered nanoporous transparent electrodes using nanosphere lithography and anodization. The self‐assembly methods used result in perfect hexagonal order over domains of thousands of square micrometers. Solar cells made from them reach significantly impr...

Soft particles such as microgels can undergo significant and anisotropic deformations when adsorbed to a liquid interface. This, in turn, leads to a complex phase behavior upon compression. To date, experimental efforts have predominantly provided phenomenological links between microgel structure and resulting interfacial behavior, while simulation...

The structure of finite self-assembling systems depends sensitively on the number of constituent building blocks. Recently, it was demonstrated that hard sphere-like colloidal particles show a magic number effect when confined in spherical emulsion droplets. Geometric construction rules permit a few dozen magic numbers that correspond to a discrete...

Bioinspired solid-state nanopores and nanochannels have attracted interest in the last two decades, as they are envisioned to advance future sensing, energy conversion, and separation concepts. Although much effort has been made regarding functionalization of these materials, multifunctionality and accurate positioning of functionalities with nanos...