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Graphical abstract Abstract Particle size reduction is a traditional approach to increase the intestinal absorption of active pharmaceutical ingredients with poor intestinal solubility, by increasing the particle dissolution rate. However, an increase in the dissolution rate cannot always fully explain the effects of nanoformulations, and a method of assessing the potential benefits of a nanoformulation in vivo would hence be of great value in drug development. A novel mathematical model of a nanoformulation, including interlinked descriptions of the hydrodynamics, particle dissolution and diffusion of particles and colloidal structures (CS), was developed to predict the combined in vivo effects of these mechanisms on drug absorption. The model successfully described previously reported in vivo observations of nanoformulated aprepitant in rats, at various drug concentrations and in the presence or absence of CS. The increase in absorption rate was explained as a direct consequence of the increased drug concentration at the membrane, caused by the contributing effects of the diffusion of both nanoparticles and CS into which the drug had partitioned. Further simulations supported the conclusion that the model can be applied during drug development to provide a priori assessments of the potential benefits of nanoformulations. [ABSTRACT FROM AUTHOR]

Developing anisotropic particles of different shapes has been a hot topic of research since decades as they possess special features not possible to achieve through other means. It is considered challenging to control atoms for developing their particles of certain size and shape. In this study, different shapes of gold particles were developed while employing a pulse-based electron–photon–solution interface process. Gold atoms, when they are in certain transition state, develop their monolayer assembly around the light glow known in argon plasma generating at the bottom of copper capillary known in cathode. The rate of uplifted gold atoms to develop monolayer assembly at solution surface is controlled by electron streams and traveling photons of high-density entering the solution. Gold atoms dissociated from the precursor on transforming photons (propagating through immersed graphite rod known in anode) to heat energy. Double-packets of nanoshape energy are generated under tuned pulse protocol when they are placed over the compact monolayer assembly resulting in tiny-sized particles of own shape. On the separation of joined tiny particles into two equilateral triangular-shaped tiny particles, each atom of their one-dimensional array elongated on both sides from the centre while exerting opposite poles forces of surface format. This results in convertion of each array of atoms into a structure of smooth elements. Due to immersing force of solution surface and their termination at the centre of light glow, tiny-shaped particles pack from different zones where their structures of smooth elements assemble to develop monolayers of developing particle in a certain shape. Developing particles of one-dimension undertake assembling of structures of smooth elements where packing of their tiny-shaped particles is from the near regions belonging to rearward sides of north–south poles at the solution surface, whereas, developing particles of multi-dimension undertake assembling of structures of smooth elements where packing of their tiny-shaped particles is from the regions of east–west poles and near regions of east–west poles on the solution surface. Depending on the number and orientation of assembled structures of smooth elements nucleating monolayers for different particles, their different anisotropic shapes develop. At fixed precursor concentration, increasing the process time results in developing particles of low aspect ratio. Under tuned parameters, particles of unprecedented features developed. Developing particles of anisotropic shapes is a challenging task, they are the hot topic of science not only in the fields of physical and chemical sciences but also in biological sciences. This study discusses the developing particles of unprecedented shapes under the setting of tuned pulse rate, precursor concentration, input power, distance between bottom of copper capillary and solution surface, total quantity of processing solution, etc. The developing of triangular-shaped tiny particles at different regions of solution surface through monolayer assembly of gold atoms and their predictor packings for developing particles of one-dimensional and multi-dimensional shapes are due to the synchronization of the process. The developed feature of tiny particles self-realized regions of their packings in pulse-based process and their packings develop particles of unprecedented features not possible through other means. [ABSTRACT FROM AUTHOR]

Abstract: Electronic garments have garnered considerable attention as a core technology for the upcoming wearable electronics era. To enable ubiquitous operation of electronic garments, they must be monolithically integrated with rechargeable power sources. Here, inspired by printing‐assisted aesthetic clothing designs, a new class of wearable supercapacitors (SCs) is demonstrated that can be directly printed on T‐shirts, which look like letters (or symbols) commonly printed on T‐shirts. The printed SCs consist of activated carbon/multiwalled carbon nanotube/ionic liquid‐based electrodes and ionic liquid/thiol‐ene polymer network skeleton/SiO2 nanoparticle‐based gel electrolytes. The rheological properties of the electrode/electrolyte pastes are fine‐tuned by varying the colloidal network structure, which affects the printing processability and formation of the nanoscale ion/electron conduction channels. To ensure the seamless unitization and design versatility of the printed SCs, the T‐shirt is sewn with electroconductive stainless steel (SS) threads prior to the printing process. Onto the SS threads acting as shape‐directing current collectors, the electrode/electrolyte pastes are sequentially stencil‐printed and sealed with water‐proof packaging films. The printed SCs exhibit exceptional form factors, flexibility, and thermal stability. Notably, the SC‐printed T‐shirts maintain their electrochemical activity upon exposure to laundering, wringing, ironing, and folding, demonstrating their potential and practical applicability as a promising electronic garment technology. [ABSTRACT FROM AUTHOR]

Magic-sized clusters (MSCs) are renowned for their identical size and closed-shell stability that inhibit conventional nanoparticle (NP) growth processes. Though MSCs have been of increasing interest, understanding the reaction pathways toward their nucleation and stabilization is an outstanding issue. In this work, we demonstrate that high concentration synthesis (1000 mM) promotes a well-defined reaction pathway to form high-purity MSCs (>99.9%). The MSCs are resistant to typical growth and dissolution processes. On the basis of insights from in situ X-ray scattering analysis, we attribute this stability to the accompanying production of a large (>100 nm grain size), hexagonal organic-inorganic mesophase that arrests growth of the MSCs and prevents NP growth. At intermediate concentrations (500 mM), the MSC mesophase forms, but is unstable, resulting in NP growth at the expense of the assemblies. These results provide an alternate explanation for the high stability of MSCs. Whereas the conventional mantra has been that the stability of MSCs derives from the precise arrangement of the inorganic structures (i.e., closed-shell atomic packing), we demonstrate that anisotropic clusters can also be stabilized by self-forming fibrous mesophase assemblies. At lower concentration (<200 mM or >16 acid-to-metal), MSCs are further destabilized and NPs formation dominates that of MSCs. Overall, the high concentration approach intensifies and showcases inherent concentration-dependent surfactant phase behavior that is not accessible in conventional (i.e., dilute) conditions. This work provides not only a robust method to synthesize, stabilize, and study identical MSC products but also uncovers an underappreciated stabilizing interaction between surfactants and clusters. [ABSTRACT FROM AUTHOR]

Multicomponent low molecular weight gels are useful for a range of applications. However, when mixing two components, both of which can independently form a gel, there are many potential scenarios. There is a limited understanding as to how to control and direct the assembly. Here, we focus on a pH-triggered two-component system. At high pH, colloidal structures are formed, and there is a degree of mixing of the two gelators. As the pH is decreased, there is a complex situation, where one gelator directs the assembly in a "sergeants and soldiers" manner. The second gelator is not fully incorporated, and the remainder forms an independent network. The result is that there is a nonlinear dependence on the final mechanical properties of the gels, with the storage or loss modulus being very dependent on the absolute ratio of the two components in the system. [ABSTRACT FROM AUTHOR]

In regenerative medicine, natural protein-based polymers offer enhanced endogenous bioactivity and potential for seamless integration with tissue, yet form weak hydrogels that lack the physical robustness required for surgical manipulation, making them difficult to apply in practice. The use of higher concentrations of protein, exogenous cross-linkers, and blending synthetic polymers has all been applied to form more mechanically robust networks. Each relies on generating a smaller network mesh size, which increases the elastic modulus and robustness, but critically inhibits cell spreading and migration, hampering tissue regeneration. Here we report two unique observations; first, that colloidal suspensions, at sufficiently high volume fraction (Φ), dynamically assemble into a fully percolated 3D network within high-concentration protein polymers. Second, cells appear capable of leveraging these unique domains for highly efficient cell migration throughout the composite construct. In contrast to porogens, the particles in our system remain embedded within the bulk polymer, creating a network of particle-filled tunnels. Whereas this would normally physically restrict cell motility, when the particulate network is created using ultralow cross-linked micro-gels, the colloidal suspension displays viscous behavior on the same timescale as cell spreading and migration and thus enables efficient cell infiltration of the construct through the colloidal-filled tunnels. [ABSTRACT FROM AUTHOR]

Herein we present a supramolecular (delayed luminescent) Eu(III)-based pH-responsive probe/sensor with the ability to detect the urease-mediated hydrolysis of urea in aqueous solution. A series of photophysical titrations show this Eu(III) chelate behaves as an "on-off" luminescent switching probe, with its luminescence being quenched upon urea being enzymatically converted into ammonia and carbon dioxide. Calculation of the rate constant (k) and activation energy (Ea) for this hydrolysis reaction are detailed; the results demonstrate a direct observation of enzymatic activity in solution by the sensor. The potential application of this probe in detecting the onset of catheter-associated urinary tract infections (CAUTIs) is also demonstrated by incorporating 1.Eu into water-permeable hydrogels that can be utilized as an alternative coating for catheters. [ABSTRACT FROM AUTHOR]

We dynamically self-assemble an active paramagnetic colloidal network that ballistically transports nonmagnetic fluorescent colloidal particles on top of the network. The transport mechanism is put into effect by a directed hydrodynamic flow, created by the rotation of individual colloids forming the network. The ballistic transport is confined to the network, and tracer beads in meshes show a diffusive instead of a ballistic transport. We develop a simple model to explain the transport. [ABSTRACT FROM AUTHOR]

Poly(fluorene-alt-thiophene) (PFT) is a conjugated polyelectrolyte that self-assembles into rod-like micelles in water, with the conjugated polymer backbone running along the length of the micelle. At modest concentrations (~10 mg/mL in aqueous solutions), PFT forms hydrogels, and this work focuses on understanding the structure and intermolecular interactions in those gel networks. The network structure can be directly visualized using cryo electron microscopy. Oscillatory rheology studies further tell us about connectivity within the gel network, and the data are consistent with a picture where polymer chains bridge between micelles to hold the network together. Addition of tetrahydrofuran (THF) to the gels breaks those connections, but once the THF is removed, the gel becomes stronger than it was before, presumably due to the creation of a more interconnected nanoscale architecture. Small polymer oligomers can also passivate the bridging polymer chains, breaking connections between micelles and dramatically weakening the hydrogel network. Fits to solution-phase small-angle X-ray scattering data using a Dammin bead model support the hypothesis of a bridging connection between PFT micelles, even in dilute aqueous solutions. Finally, time-resolved microwave conductivity measurements on dried samples show an increase in carrier mobility after THF annealing of the PFT gel, likely due to increased connectivity within the polymer network. [ABSTRACT FROM AUTHOR]

We derive a constitutive relation to describe the deformation of a two-dimensional strongly aggregated colloidal system by incorporating the interparticle colloidal forces and contact dynamics. The theory accounts for the plastic events that occur in the form of rolling/sliding during the deformation along with elastic deformation. The theory predicts a yield stress that is a function of volume fraction of the colloidal packing, the coordination number, the interparticle potential, coefficient of friction, and the normal and the tangential stiffness coefficients. The predicted yield strain was independent of the particle volume fraction although the compressive yield stress exhibited a power-law relation with the volume fraction. The power-law exponent, however, was lower than that obtained from simulations reported in a paper by Roy and Tirumkudulu ["Yielding in a strongly aggregated colloidal gel. Part I: 2D simulations," J. Rheol. 60(4), 559-574 (2016)]. The cause for the discrepancy was identified to be the nonaffine deformation of the network. To account for such effects, a constitutive relation based on a simple fractal model was developed that predicts yield stress profile close to those obtained from simulations. [ABSTRACT FROM AUTHOR]

We investigate the microstructure details and the mechanical response under uniaxial compression of a strongly aggregating colloidal dispersion. The numerical simulations account for short-range interparticle attraction, normal and tangential deformation at particle contacts, sliding and rolling resistance (RR), and preparation conditions. The compression rates are small so that hydrodynamic interactions are negligible. In the absence of RR, the average coordination number varies only slightly with compaction while the variation is significant in its presence. The particle contact distribution is isotropic throughout the consolidation process, irrespective of the magnitude of the parameters. In this limit of strong aggregation, the elastic modulus is a weak function of the magnitude of attraction. It is shown that the yield strain does not change significantly during the entire consolidation process, and the value in the presence of RR is marginally higher than in its absence. However, the yield stress increases with volume fraction which is a direct consequence of the increased elastic modulus. The yield stress, both in the presence and absence of RR, scales similarly with volume fraction. The overall power law exponent of 5.7 of the yield stress in the presence of RR as a function of volume fraction is in good agreement with previous simulation results. [ABSTRACT FROM AUTHOR]

This article reviews recent research on the collective dynamical behavior of colloids with dipolar or multipolar interactions. Indeed, whereas equilibrium structures and static self-assembly of such systems are now rather well understood, the past years have seen an explosion of interest in understanding dynamicals aspects, from the relaxation dynamics of strongly correlated dipolar networks over systems driven by time-dependent, electric, or magnetic fields, to pattern formation and dynamical control of active, self-propelled systems. Unraveling the underlying mechanisms is crucial for a deeper understanding of self-assembly in and out of equilibrium and the use of such particles as functional devices. At the same time, the complex dynamics of dipolar colloids poses challenging physical questions and puts forward their role as model systems for nonlinear behavior in condensed matter physics. Here we attempt to give an overview of these developments, with an emphasis on theoretical and simulation studies. [ABSTRACT FROM AUTHOR]

Rheological properties, gel networkstructures, and scaling laws for κ-carrageenan in aqueous solutionwere studied by rheology and field emission scanning electron microscopy(FESEM). The FESEM micrographs verified that the κ-carrageenangels were formed by the formation of fibrils. The critical gel concentration, cg, obtained using the Winter–Chamboncriterion, was found to be proportional to temperature as expressedby cg∼ T0.85where Tis the temperature in °C.At the gel point, the critical relaxation exponent nobtained was a constant (n= 0.62) and independentof temperature. The critical gel strength Sgincreased with increasing cg. A constantgel strength Sg/cgwas obtained by normalizing Sgwith cgto eliminate the effect of temperature,showing a unique character of κ-carrageenan in aqueous solutionduring gelation. The molecular structure of the junctions at the gelpoint was analyzed using the modified Eldridge–Ferry model,which supported the similarity of the fractal structure in the κ-carrageenangels. Before the gel point, the zero shear viscosity η0of κ-carrageenan solutions diverged as the gelling systemapproached to the gel point, and a scaling law, η0∼ ε–γ, was established, whereε is the relative distance of κ-carrageenan concentration cfrom cgand γ is thescaling exponent that was found to be 1.6. Beyond the gel point, theplateau modulus Geof κ-carrageenangels depended on the polymer concentration according to a power law, Ge∼ εz, where zwas found to be 2.7. The critical gelexponent nevaluated from γ and zagreed well with the value of ndetermined fromthe Winter–Chambon criterion, further indicating that the characteristicrelaxation time of the pregel and the postgel follows the same powerlaw (symmetry at c= cg) for κ-carrageenan in aqueous solution. [ABSTRACT FROM AUTHOR]

From experimental studies, it is well known that colloidal particles suspended in a near-critical binary solvent exhibit interesting aggregation phenomena, often associated with colloidal phase transitions and assumed to be driven by long-ranged solvent-mediated (SM) interactions (critical Casimir forces), set by the (diverging) correlation length of the solvent. We present the first simulation and theoretical study of an explicit model of a ternary mixture that mimics this situation. Both the effective SM pair interactions and the. full ternary phase diagram are determined for Brownian disks suspended in an explicit two-dimensional supercritical binary liquid mixture. Gas-liquid and fluid-solid transitions are observed in a region that extends well away from criticality of the solvent reservoir. We discuss to what extent an effective pairpotential description can account for the phase behavior we observe. Our study provides a fresh perspective on how proximity to the critical point of the solvent reservoir might influence colloidal self-assembly. [ABSTRACT FROM AUTHOR]

Harnessing the optical properties of noble metals down to the nanometre scale is a key step towards fast and low-dissipative information processing. At the 10-nm length scale, metal crystallinity and patterning as well as probing of surface plasmon properties must be controlled with a challenging high level of precision. Here, we demonstrate that ultimate lateral confinement and delocalization of surface plasmon modes are simultaneously achieved in extended self-assembled networks comprising linear chains of partially fused gold nanoparticles. The spectral and spatial distributions of the surface plasmon modes associated with the colloidal superstructures are evidenced by performing monochromated electron energy-loss spectroscopy with a nanometre-sized electron probe. We prepare the metallic bead strings by electron-beam-induced interparticle fusion of nanoparticle networks. The fused superstructures retain the native morphology and crystallinity but develop very low-energy surface plasmon modes that are capable of supporting long-range and spectrally tunable propagation in nanoscale waveguides. [ABSTRACT FROM AUTHOR]

Triacylglycerols (TAGs) are the majority molecules present in edible fats and oils. Many of the functional characteristics of fat products depend on the colloidal fat crystal network present. Identifying the hierarchies of these colloidal networks and how they spontaneously self-assemble is important to understand their functionality and the oil binding capacity, and new insights into the nano- to meso-scale structure in these colloidal fat networks have been reported in recent years. Ultra small angle X-ray scattering (USAXS) is a technique new to the study of edible oil structures and, when combined with modelling and computer simulation, has enabled significant advances to be made in understanding the nano- to micro-scale crystalline structures of edible oils. In the four years since crystalline nanoplatelets (CNPs) were characterized, models have been made of these highly anisotropic nanoscale structures in which they were treated as the primary unit. In those models, CNPs were represented as close-packed rigid layers of spheres, so chosen because the van der Waals sphere–sphere interaction is known. The intent of the models was to predict the hierarchy of colloidal fat networks that would self-assemble from the components in edible oils. Initially, CNP aggregation was modelled under the assumption that all CNPs are present before aggregation begins and that their solubility in liquid oil is very low. The models successfully predicted the fractal dimensions subsequently measured using USAXS. This brief review reports on some of the latest models and simulations together with the results of USAXS experiments carried out on binary lipid systems, such as SSS in OOO, as well as certain complex systems that contain many different TAG molecules. The excellent agreement between the two approaches has established that USAXS is a powerful tool in the elucidation of the nano- to meso-length scales in fats and oils. [ABSTRACT FROM AUTHOR]

Hydrogels wit h interpenetrating network (IPN) can overcome thermodynamic incompatibility and obtain transparent materials with limited phase separation. In this report, hydroxyl-grafting polysiloxane (HPSO) was synthesized and transparent silicone hydrogels with interpenetrating network were simultaneously prepared based on radical polymerization of methacrylic monomer of 3-methacryloxypropyl tris(trimethylsiloxy)silane/N,N-dimethylacrylamide and addition polymerization of HPSO/isophorone diisocyanate. The silicone hydrogels were characterized by dehy-dration kinetics, tensile tester, light transmittance, ion permeability, oxygen perme-ability, and lysozyme deposition. The results show that increasing the proportion of hydrophobic network of HPSO in the IPN silicone hydrogel decreases equilibrium swelling ratio, ion permeability, Young's modulus, and lysozyme deposition; on the contrary, increased tensile strength, elongation at break and oxygen permeability. Puerarin and ketoconazole were used as models to evaluate the drug loading and in vitro release behavior of the silicone hydrogels. It is revealed that the amount of loaded drugs in the hydrogel decreases with the increase of HPSO network in the hydrogels. All the silicone hydrogels exhibit extended release behavior, especially for ketoconazole, the in vitro release is divided into two phases corresponding to the rapid release at initial 24 h and relatively slow release from 125 to 360 h. [ABSTRACT FROM AUTHOR]

In this study, we present two approaches to developing composite electrolytes exploiting the self-assembling nature of colloidal fillers. The first system comprises of oligomers of poly(ethylene glycol) dimethyl ether, branched fumed silica particulates and lithium salt. The fumed silica forms a three-dimensional, self-supporting network that provides mechanical stability. The large pores of the network has little effect on diffusivity of ions and oligomers, lithium transference number and ionic conductivity, with the latter showing values >10−3 S/cm at ambient conditions. The second system consists of Li exchanged hectorite clay in a mixture of low molar mass carbonates. Similar to the fumed silica, the clay provides mechanical stability through formation of a three-dimensional network. In addition, the immobile clay platelets also serve as the anion rendering the system to be a single ion conductor. Near-unity transference number is observed in this case. However, the room temperature conductivity of the clay composite is lower than the fumed silica, revealing a value of about 10−4 S/cm. The lower conductivity can be attributed to the clay not being in a fully exfoliated form as evident from morphological analysis. [Copyright &y& Elsevier]

A supramolecular gel was fabricated through mixing of a cationic gelator with methyl orange. The addition of ATP into the gel caused a distinct gel-collapse, whereas ADP and AMP preserved the gel formation. This observation provided a simple visualized way to discriminate ATP from AMP and ADP. [ABSTRACT FROM AUTHOR]

Abstract.: The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory is widely used to model interactions between weakly charged spheres in dilute suspensions. For particles bearing a higher charge, the linearized electrostatics underlying the DLVO theory is no longer valid but it is possible to map the real colloidal system to an auxiliary one that still obeys linear electrostatics but which involves a different, effective pair potential. This procedure, termed renormalization, can be performed in various ways, the most widely used being surface charge renormalization (SCR) based on the cell model. SCR is still limited to dilute suspensions since the auxiliary system is made of spheres interacting through a DLVO-like pair potential. The recent extrapolated point charge (EPC) renormalization overcomes this limitation by using point charges in the auxiliary system and has indeed been shown to produce better results than the SCR in dense suspensions. Here, we recall that the DLVO-like potential used in the SCR can be modified to account for many-body ion-colloid core exclusion effects (a model termed SCRX here); we show that the accuracy of the EPC and SCRX renormalizations is virtually identical, and conclude by explaining why the EPC method is still the most attractive option of the two in many cases.Graphical abstract: [ABSTRACT FROM AUTHOR]

Magnetically actuated swimming of microscopic objects has been attracting attention partly due to its promising applications in the bio-medical field and partly due to interesting physics of swimming in general. While colloidal particles that are free to move in fluid can be an attractive swimming system due it its simplicity and ability to assemble in situ, stability of their dynamics and the possibility of stable swimming behavior in periodically varying magnetic fields has not been considered. Dynamic behavior of two magnetically interacting colloidal particles subjected to rotating magnetic field of switching frequency is analyzed here and is shown to result in stable swimming without any stabilizing feedback. A new mechanism of swimming that relies only on rotations of the particles themselves and of the particle pair axis is found to dominate the swimming dynamics of the colloidal particle pair. Simulation results and analytical arguments demonstrate that this swimming strategy compares favorably to dragging the particles with an external magnetic force when colloidal particle sizes are reduced. [ABSTRACT FROM AUTHOR]

A safe and efficient nanocomposite hydrogel for colon cancer drug delivery was synthesized using pH-sensitive and biocompatible graphene oxide (GO) containing azoaromatic crosslinks as well as poly (vinyl alcohol) (PVA) (GO–N=N–GO/PVA composite hydrogels). Curcumin (CUR), an anti-cancer drug, was encapsulated successfully into the hydrogel through a freezing and thawing process. Fourier transform infrared spectroscopy, scanning electron microscopy and Raman spectroscopy were performed to confirm the formation and morphological properties of the nanocomposite hydrogel. The hydrogels exhibited good swelling properties in a pH-sensitive manner. Drug release studies under conditions mimicking stomach to colon transit have shown that the drug was protected from being released completely into the physiological environment of the stomach and small intestine. In vivo imaging analysis, pharmacokinetics and a distribution of the gastrointestinal tract experiment were systematically studied and evaluated as colon-specific drug delivery systems. All the results demonstrated that GO–N=N–GO/PVA composite hydrogels could protect CUR well while passing through the stomach and small intestine to the proximal colon, and enhance the colon-targeting ability and residence time in the colon site. Therefore, CUR loaded GO–N=N–GO/PVA composite hydrogels might potentially provide a theoretical basis for the treatment of colon cancer with high efficiency and low toxicity. [ABSTRACT FROM AUTHOR]

We investigate a model for colloidal network formation using Brownian dynamics computer simulations. Hysteretic springs establish transient bonds between particles with repulsive cores. If a bonded pair of particles is separated by a cutoff distance, the spring vanishes and reappears only if the two particles contact each other. We present results for the bond lifetime distribution and investigate the properties of the van Hove dynamical two-body correlation function. The model displays crossover from fluidlike dynamics, via transient network formation, to arrested quasistatic network behavior. [ABSTRACT FROM AUTHOR]

We present an experimental study on the influence of annealing temperature on morphological changes of colloidal silver nanoparticles (Ag NPs) and their optical response. Monodisperse colloidal Ag NPs with diameter of 164 nm ± 15 nm have been fabricated by a facile two-step synthesis approach. The annealing effects on the Ag NPs have been investigated by means of optical measurements, scanning electron microscopy, x-ray photoelectron spectroscopy and x-ray diffraction. By annealing up to 440 °C morphology and chemical compositions of the Ag NPs changed. These changes affect the particle size and distribution, surface morphology, crystallinity and, most importantly, the oxidation state of the surface layer. The removal of an oxide layer leads to stronger light scattering from the nanoparticles and decreases parasitic light absorption at wavelengths above 400 nm. Strong light trapping has been observed for a silicon thin film with embedded annealed Ag NPs. This study demonstrates that colloidal Ag NPs for plasmonic solar cells need to be carefully processed and that they can potentially achieve high scatter efficiencies. [ABSTRACT FROM AUTHOR]