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Polymeric biomaterials such as polylactic acid (PLA) play a prominent role in the advancement of biomedical additive manufacturing (AM). PLA offers indeed a very advantageous combination of thermo-mechanical properties and functional attributes, as it is biobased, biodegradable, biocompatible and easy to print. However, PLA can be damaged by common sterilization methods and is sensitive to most chemical disinfectants, and this may impair its widespread usage. One of the most promising ways to overcome this shortcoming is to provide PLA with embedded antibacterial activity by the addition of appropriate fillers such as ZnO nanoparticles. After a detailed introduction to the basic properties of PLA and ZnO nanoparticles, the present review analyzes the main variables that govern the antibacterial activity of PLA-ZnO nanocomposites. Current applications and related manufacturing processes are also presented to showcase the importance of having embedded antibacterial functions in demanding fields such as food packaging and wound dressing. Emphasis is then placed on the emerging literature of the AM of PLA-ZnO nanocomposites, with a focus on fused filament fabrication (also known as fused deposition modeling). Existing gaps and hurdles related to the development and 3D printing of such composites are critically discussed. It is envisioned that a deeper understanding of the processability, thermo-mechanical behavior, biocompatibility and anti-bacterial efficacy of additively manufactured PLA-ZnO nanocomposites will foster their adoption in the biomedical field and, ultimately, in all circumstances where it is crucial to limit infection transmission.

A SiO2-coumarin nanohybrid was investigated for its Cu(II) sensing performance in aqueous media, and in comparison with the Cu(II)-selective coumarin used alone. Fluorescence of both coumarin itself and the nanohybrid, λex/λem 435/481 nm, was selectively quenched by Cu(II) when tested against a range of multivalent cations. The nanohybrid had enhanced Cu(II) sensing properties when compared to the coumarin including (i) improved limit of detection from μM-level (0.48 μM) of Cu(II) using coumarin alone to nM-level (0.033 μM) and (ii) an extended linear detection range of 0.033–260 μM (0.0005–4.1 mg/mL) Cu(II) compared to 0.48–55 μM for the coumarin itself. The lower limit of detection and extended range were achieved with a smaller amount of coumarin and no traces of organic solvents used to help coumarin dissolution. Characterization suggested that under applied test conditions at pH = 5, SiO2 nanoparticles with negative surface charges adsorbed coumarin and then (when present) Cu(II) ions. The SiO2-coumarin nanohybrid was then applied for the determination of Cu(II) levels in aqueous soil extracts reaching over 94% recovery rates when used against the standard soil analysis method by inductively coupled plasma mass spectrometry (ICP-MS). Graphical Abstract

We report a sensitive, yet low-cost biosensor based on laser induced graphene for femtomolar microRNA (miRNA) detection. Combined with the miRNA extraction and magnetic isolation process, the target miRNAs were purified for further detection using laser induced graphene sensor. The laser induced graphene was prepared by direct laser writing on commercial polyimide (PI) and patterned via a computer-aided design system as an electrode for electrochemical biosensing. We found that the laser reduction of PI resulted in nitrogen-doped porous graphene, not only improving its conductivity but also its sensitivity to nucleic acids. Preeclampsia specific miRNA hsa-miR-486-5p was magnetically purified and directly adsorbed on the surface of graphene electrode via graphene-miRNA affinity interaction. Surface attached miRNAs were then electrochemically quantified using [Fe(CN)6]3-/4- redox system. Our assay demonstrates detection of miRNA has-miR-486-5p up to concentrations as low as 10 fM with excellent reproducibility. Owing to its facile fabrication, low cost and high performance, the laser induced N-doped graphene biosensor presented here shows great potential for applications in detecting miRNA in biomedical applications.

Carbon dots (CDs) with N- and Cl-contained groups supported mesoporous hydroxyapatite (mHA) composites were prepared, respectively. The effect of the interfacial reaction between CDs and mHA on the photocatalytic activity was investigated. It was found that the composites exhibited different compositions and absorption properties owing to the interfacial reaction. As a consequence, while CDs with Cl-contained groups (Cl-CDs) showed the highest activity, mHA/Cl-CDs composite exhibited the lowest activity. Conversely, the composite of mHA and CDs with N-contained groups using ammonia as source (N-CDs-1) had the highest activity, although the activity of N-CDs-1 was lower that of Cl-CDs. It can be concluded that the interfacial reaction played an essential role in governing the activity of the composites. The findings were valuable in constructing CDs-based composites with excellent photocatalytic performance.

Additive manufacturing (AM) of orthopedic implants is growing in popularity as it offers almost complete design flexibility and freedom, meaning complex geometries mimicking specific body parts can be easily produced. Novel composite materials with optimized functionalities present opportunities for 3D printing osteoconductive implants with desirable mechanical properties. Standard metals for bone implants, such as titanium and its alloys, are durable and nontoxic but lack bioactivity. Bioactive glasses promote strong bone formation but are susceptible to brittle failure. Metal-bioactive glass composites, however, may combine the mechanical reliability of metals with the bone-bonding ability of bioactive glasses, potentially reducing the incidence of implant failure. Processing such composites by AM paves the way for producing unprecedented bespoke parts with highly porous lattices, whose stiffness can be tailored to meet the mechanical properties of natural bone tissue. This Perspective focuses on titanium-bioactive glass composites, critically discussing their processability by AM and highlighting their potential as a next-generation implantable biomaterial.

In this study, a hydroxyl-rich Schiff base ligand, H4L, and its resulting complexes with ZnCl2, Zn(CH3COO)2 and Zn(ClO4)2 were explored. Interestingly, depending on the zinc salt and/or the crystallisation method, four unique structures were obtained. A synthesis with ZnCl2 gave 1, a mononuclear structure ((H3L)2Zn), while with Zn(CH3COO)2, a trinuclear system [(H3L)2Zn3(CH3COO)4], 2, was found. Interestingly two multinuclear architectures were observed with Zn(ClO4)2. Firstly, diethyl ether diffusion of a methanolic reaction mixture with minimal atmospheric air volume gave 3, a hexanuclear architecture of the type [(H2L)4(H3L)2Zn6](ClO4)2, while slow evaporation of a similar mixture gave 4, a nonanuclear architecture with the formula [(H2L)6Zn9(CO3)2](ClO4)2. Compound 4 unexpectedly fixed atmospheric CO2 as CO32−, incorporating it into the architecture. As expected, a diethyl ether diffusion with a larger volume of air (∼100 mL) of a similar methanolic reaction mixture gave a mixture of 3 and 4. In addition, bulk samples of all compounds were also investigated by PXRD, and results are in good agreement with the observed single crystal data. Furthermore, complexes 1–4 were characterised using FT-IR and simultaneous thermal analysis (STA), and additionally the photophysical properties of H4L and complexes 1–4 have also been explored.

The Griess reaction is the most often exploited colorimetric method for the quantitative analysis of nitrite in aqueous media. The application of the currently used reagents are associated with limitations (e.g. linear response range). Herein, molecular fingerprint searching on well-known Griess-reagents was used as a tool for the identification of structurally similar, new reagent candidate molecules. Rapid and high-throughput experimental evaluation of the newly identified Griess-reagent candidates revealed that 14 of the 18 tested reagent candidates had equal or superior response displaying broader linear ranges and/or increased response gradient against various nitrite concentrations in aqueous media when compared to the parent compounds at room temperature.

Fluorescent carbon dots (CDs) with excitation-wavelength-dependent and excitation-wavelength-independent emission have been prepared with varying amounts citric acid (CA), ethylenediamin end-capped polyethylenimine (PEI-EC) and sodium borohydride (NaBH 4 ), their structure, optical and chemical sensing properties have been also systematically investigated. The varying of NaBH 4 and PEI-EC renders the structure and surface state change as well as photoluminescence (PL) properties. The results indicated that NaBH 4 made the CDs sensitive to Co 2+ ions, whilst the PEI-EC served to increase their sensitivity. The synergistic roles that both NaBH 4 and PEI-EC played on the selective and sensitive detection of Co 2+ were achieved via a simple adjustment of the mass ratios during synthesis. Furthermore, the PL intensity was gradually recovered until completely restored with the addition of chelating agent ethylenediaminetetraacetic acid (EDTA) to the Co 2+ quenched CDs solutions. This work provided quantitatively preparation and controllable synthesis of excitation-wavelength-dependent or independent CDs for the development of PL based sensors.

A new and highly efficient colorimetric Cu2+ chemosensor HL, synthesized by condensation between 8-hydroxyjulolidine-9-carboxaldehyde and 1,8-diaminonaphthalene, has been rationally designed and thoroughly studied. In a buffered aqueous methanol mixture, interactions between HL and Cu2+ produce an intense visible band at 421 nm, considerably red-shifted (~ 100 nm) from the peak maxima of HL (320 nm). Absorbance spectrophotometry experiments pointed to an exceptional 2.3 nM limit of detection (LoD) calculated from the ratiometric response upon Cu2+ binding. Furthermore, without the aid of instrumentation an impressive 0.5 µM LoD is possible by naked-eye observations, far below the 31.5 µM (2 mg/L) guidelines for drinking water established by the World Health Organization. Spectrophotometric pH titrations allowed the determination of the equilibrium constants and speciation plots for the formation of the various chemical species of HL in the absence and presence of Cu2+, with only mononuclear complexes being found. Additional studies highlighted the selectivity of HL to Cu2+ when in the presence of other metal ions, and a 1:1 (M:L) binding stoichiometry has also been confirmed with results from Cu2+ titrations, Job’s plot and ESI-HRMS in good agreement. The Cu2+ sensing mechanism was also found to be reversible by cycling with H2Na2EDTA.

Herein, we report the synthesis and characterization of a chemosensor, 5-(diethylamino)-2-(2,3-dihydro-1H-perimidin-2-yl)phenol (HL), synthesized from a condensation between 4-(diethylamino)salicylaldehyde and 1,8-diaminonaphthalene. Upon investigation of the sensing properties of HL, it was found that this sensor may be employed for simple yet efficient detection of Cu2+ in aqueous methanol solutions. The selective and ratiometric response to Cu2+ yielded an outstandingly low limit of detection of 3.7 nM by spectrophotometry and is also useful as a naked-eye sensor from 2.5 μM. The system was studied by spectrophotometric pH titrations to determine Cu2+ binding constants and complex speciation. Binding of Cu2+ to HL occurs in 1:1 stoichiometry, in good agreement with high-resolution electrospray ionization mass spectrometry (ESI-HRMS) results, Cu2+ titrations, and Job's plot experiments, while the coordination geometry was tentatively assigned as square pyramidal by spectroscopic studies.

Additive manufacturing (AM) is rapidly evolving from “rapid prototyping” to “industrial production”. AM enables the fabrication of bespoke components with complicated geometries in the high-performance areas of aerospace, defence and biomedicine. Providing AM parts with a tagging feature that allows them to be identified like a fingerprint can be crucial for logistics, certification and anti-counterfeiting purposes. Whereas the implementation of an overarching strategy for the complete traceability of AM components downstream from designer to end user is, by nature, a cross-disciplinary task that involves legal, digital and technological issues, materials engineers are on the front line of research to understand what kind of tag is preferred for each kind of object and how existing materials and 3D printing hardware should be synergistically modified to create such tag. This review provides a critical analysis of the main requirements and properties of tagging features for authentication and identification of AM parts, of the strategies that have been put in place so far, and of the future challenges that are emerging to make these systems efficient and suitable for digitalisation. It is envisaged that this literature survey will help scientists and developers answer the challenging question: “How can we embed a tagging feature in an AM part?”.

Hybrid nanostructures comprising disparate materials and having intricate shapes and facets are highly desired in photocatalytic applications requiring high selectivity. However, to produce such structures requires precise morphological control, and this is largely dictated by the stringent requirements of the reaction conditions, in addition to intricate, expensive, or tedious preparation steps. We present a simple, inexpensive, and scalable method for the preparation of hybrid nanostructures that combines carbon dots with hexagonal nanoplates of nickel-based compounds. The resultant heterostructure not only improves visible light absorption, but also exhibits enhanced photocatalytic activity for the reduction of 4-nitrophenol to 4-aminophenol when compared to carbon dots or hexagonal nanoplates of nickel-based compounds alone. The enhanced photocatalytic activity is due to the higher separation and transfer efficiency of photoexcited charge carriers at the interface between the carbon dot and hexagonal nanoplate of nickel-based compounds. This work opens up a straightforward and effective route to yield inexpensive and efficient photocatalysts for improved solar energy capture and conversion.

We have firstly prepared CsPbBr3@SiO2 nanocomposites with a spherical morphology and diameters less than 125 nm via confined condensation into polystyrene. The obtained CsPbBr3@SiO2 exhibits high stability in polar solvents and can be used as a solution-processable luminescent ink.

A series of fluorescent coumarin derivatives 2a&ndash, e were systematically designed, synthesized and studied for their Cu2+ sensing performance in aqueous media. The sensitivities and selectivities of the on-to-off fluorescent Cu2+ sensing signal were in direct correlation with the relative arrangements of the heteroatoms within the coordinating moieties of these coumarins. Probes 2b and 2d exhibited Cu2+ concentration dependent and selective fluorescence quenching, with linear ranges of 0&ndash, 80 &mu, M and 0&ndash, 10 &mu, M, and limits of detection of 0.14 &mu, M and 0.38 &mu, M, respectively. Structural changes of 2b upon Cu2+ coordination were followed by fluorescence titration, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), mass spectrometry, and single crystal X-ray diffraction on the isolated Cu2+-coumarin complex. The results revealed a 1:1 stoichiometry between 2b and Cu2+, and that the essential structural features for Cu2+-selective coordination are the coumarin C=O and a three-bond distance between the amide NH and heterocyclic N. Probe 2b was also used to determine copper (II) levels in aqueous soil extracts, with recovery rates over 80% when compared to the standard soil analysis method: inductively coupled plasma-mass spectrometry (ICP-MS).

Laser reduced graphene has been increasingly attracting broad attention owing to its unique properties and potential applications in energy conversion and storage, flexible electronics, optoelectronics, and nanocomposites. In this study, graphene sheets decorated with Au nanoparticles are fabricated in situ using milliwatt femtosecond laser reduction. The findings reveal an enhancement in both the reduction of graphene oxide sheets and the nucleation and growth of the Au nanoparticles during the in situ laser treatment. Three stages of reactions are considered, namely, (i) the spontaneous redox reaction between HAuCl4 and graphene oxide, (ii) the laser‐induced decomposition of HAuCl4 and reduction of graphene oxide, and (iii) the localized surface plasmon resonance enhanced photoreduction in the presence of Au particles. Moreover, the Au nanoparticles form densely and evenly distributed square‐lattice‐like microcrack networks that ensure a linear resistance change over the tested strain range. This microcrack network architecture enables the development of flexible graphene/Au strain sensors with gauge factors up to 52.5, and linear behaviour up to 25.4% strain. This strain sensor is demonstrated to effectively monitor human motions. The findings leverage the resistive properties of graphene/metal nanoparticle composites with fundamental mechanisms, laying a critical step toward highly functional, low‐cost, flexible, and wearable graphene‐based electronics.

One of the most widely used methods for exfoliating crystalline nanocarbon is via strong oxidizing acid treatment of bulk carbon sources, such as graphite, carbon black and coal. Not only is such method dangerous and accompanied by the liberation of toxic gases, it is also plagued by issues of purity, requiring the thorough and costly removal of the excess oxidizing acids and salts formed during the process. Herein we report a facile, green and inexpensive top-down strategy towards fluorescent carbon dots (CDs) from coal without incurring the burden of tedious or inefficient post-processing steps and facing the danger of highly toxic gas liberation. The presented approach shows a high yield and great potential for carbon dot production scale-up using coal, one of our most abundant and low-cost resources. The prepared CDs demonstrate photocatalytic behavior capable of rapidly degrading organic dyes under visible light. Our findings may lead to alternative uses of coal, particularly for applications including the treatment of environmental pollution, solar energy conversion or storage, and highlight coal’s applicability in areas other than energy producing via burning of this great resource.

The Griess reaction is the most often exploited colorimetric method for the quantitative analysis of nitrite in aqueous media. The application of the currently used reagents are associated with limitations (

Despite their impressive optical properties, lead halide perovskite quantum dots (PQDs) have not realized their potential, especially in bioimaging applications, as they suffer from poor moisture and thermal stability, solvent incompatibility, and significant toxicity. Here, a spray-assisted coil-globule transition method for encapsulating CsPbBr

Two-dimensional (2D) tungsten disulfide (WS2) nanoflakes were synthesised and hybridised with carbon dots (CDs) using a facile two-step method of exfoliation of bulk tungsten disulphide followed by microwave irradiation of nanoflakes in a solution of citric acid. Physicochemical characterisation indicated that the hybrid consists of graphitic carbon dots with diameters of approximately 2–5 nm, attached to monolayer tungsten disulphide via electrostatic attraction forces. This synthesised hybrid material was investigated for photocatalytic applications. We found that within one hour approximately 30% more of the model organic dye was photodegraded by the hybrid material compared with the pristine 2D WS2. This enhancement was associated to the affinity of the CDs to the organic dye rather than heterojunctioning. Comparisons of the photocatalytic efficacy of this hybrid material with those of recently reported 2D transition metal dichalcogenides and their hybrids showed a significantly higher turnover frequency. Additionally, the presented microwave based synthesis method for developing hybrids of 2D WS2 and CDs, without making significant changes to the base 2D crystal structure and its surface chemistry, has not been demonstrated before. Altogether, the hybrid 2D material provides great potential for photocatalysis applications.

Here we report the fluorescence response of water dispersible CdSe/ZnS core–shell quantum dots capped with 2-mercaptopropionic acid (2MPA) towards different concentrations of heavy metal cations, namely mercury, lead and cadmium. Upon exposure to different concentrations of the various metal cations, a concentration-dependent decrease in the QDs’ fluorescence emission was observed, which was decaying exponential in nature. The greatest degree of quenching was achieved in the presence of mercury. The resultant quantum dots were subsequently characterised by UV–vis spectroscopy, photo-luminescent spectroscopy, Raman Spectroscopy and X-ray diffraction. The quantitative detection of mercury, lead and cadmium cations by these capped quantum dots makes them exciting candidates for heavy metal sensing applications.

Fluorescent quantum dots (QDs) are semiconducting nanocrystals (NCs) that find numerous applications in areas, such as bio labelling, sensors, lasers, light emitting diodes and medicine. Core-shell quantum dots were developed to improve the photoluminescence efficiency of single quantum dots. Capping their surface with organic ligands as well as their extraction into aqueous media enables their use in sensing applications. The current review highlights the importance and applications of core shell quantum dots as well as their surface modifications and applications in the field of medicine and as sensors for chemical and biochemical analysis.

Although reports have shown shifts in carbon dot emission wavelengths resulting from varying the excitation wavelength, this excitation-dependent emission does not constitute true tuning, as the shifted peaks have much weaker intensity than their dominant emission, and this is often undesired in real world applications. We report for the first time the synthesis and photoluminescence properties of carbon dots whose peak fluorescence emission wavelengths are tunable across the entire visible spectrum by simple adjustment of the reagents and synthesis conditions, and these carbon dots are excited by white light. Detailed material characterization has revealed that this tunable emission results from changes in the carbon dots' chemical composition, dictated by dehydrogenation reactions occurring during carbonization. These significantly alter the nucleation and growth process, resulting in dots with either more oxygen-containing or nitrogen-containing groups that ultimately determine their photoluminescence properties, which is in stark contrast to previous observations of carbon dot excitation-dependent fluorescence. This new ability to synthesize broadband excitable carbon dots with tunable peak emissions opens up many new possibilities, particularly in multimodal sensing, in which multiple analytes and processes could be monitored simultaneously by associating a particular carbon dot emission wavelength to a specific chemical process without the need for tuning the excitation source.

The transition from nanoparticles suspended in aqueous solutions into solid fluorescent structures is developed for application in solid functional devices. The presented approach enables the organization of carbon dots into rod-like shapes that can still be re-dispersed into aqueous solution. Schiff bases forming at the surface of carbon dots not only protect their surface states, but also provide sites for tethering to other carbon dots. As a consequence, the large assemblies of CDs can come together to form regular, well ordered structures whilst still maintaining their photoluminescence properties. This opens up enormous possibilities for device manufacture, as these self-assemblies could be grown or grafted onto templates forming regular structures, and find innumerable applications ranging from optoelectronic devices, light harvesting to artificial photosynthesis.

Copper ion (Cu(2+)) and L-cysteine (L-Cys) detection is critically important since an abnormal level of Cu(2+) or L-Cys is an indicator for many diseases. In this paper, we demonstrate an "off-on" approach for highly sensitive and selective detection of Cu(2+) and L-Cys using carbon dots (CDs) as fluorescent probes. CDs were prepared by using mesoporous silica (MS) spheres as nanoreactors. The binding ability of CDs towards metal ions was examined by comparing the fluorescence intensities of CDs before and after the addition of the metal ions. The addition of Cu(2+) cations leads to their absorption on the surface of CDs and the significant fluorescence quench of CDs (turn-off). The resulting in CDs-Cu(2+) system was found to be sensitive to L-Cys. The addition of L-Cys not only serves to shelter the CDs effectively from being quenched, but also to reverse the quenching and restore the fluorescence (turn-on) due to its ability to remove Cu(2+) from the surface of CDs. This method is facile, rapid, low cost, and environment-friendly. A detection limit as low as 2.3×10(-8) M for Cu(2+) and 3.4×10(-10) M for L-Cys is obtained, which is promising for biological applications.

This work describes preliminary steps towards nano-scale reservoir computing using quantum dots. Our research has focused on the development of an accumulator-based sensing system that reacts to changes in the environment, as well as the development of a software simulation. The investigated systems generate nonlinear responses to inputs that make them suitable for a physical implementation of a neural network. This development will enable miniaturisation of the neurons to the molecular level, leading to a range of applications including monitoring of changes in materials or structures. The system is based around the optical properties of quantum dots. The paper will report on experimental work on systems using Cadmium Selenide (CdSe) quantum dots and on the various methods to render the systems sensitive to pH, redox potential or specific ion concentration. Once the quantum dot-based systems are rendered sensitive to these triggers they can provide a distributed array that can monitor and transmit information on changes within the material., Comment: 8 pages, 9 figures, accepted for publication in Nano Communication Networks, http://www.journals.elsevier.com/nano-communication-networks/. An earlier version was presented at the 3rd IEEE International Workshop on Molecular and Nanoscale Communications (IEEE MoNaCom 2013)

Conventional X-ray microcomputed tomography (micro-CT) is not usually sufficient to determine microscopic compositional distributions as it is limited to measuring the X-ray attenuation of the sample, which for a given dataset can be similar for materials of different composition. In contrast, the present work enables three-dimensional compositional analysis with a data-constrained microstructure (DCM) modeling methodology, which uses two or more CT datasets acquired with different X-ray spectra and incorporates them as model constraints. For providing input data for DCM, we have also developed a method of micro-CT data collection that enables two datasets with different X-ray spectra to be acquired in parallel. Such data are used together with the DCM methodology to predict the distributions of corrosion inhibitor and filler in a polymer matrix. The DCM-predicted compositional microstructures have a reasonable agreement with energy dispersive X-ray images taken on the sample surface.

Many 21st century technological solutions are reliant on the development of new materials with improved properties, and increasingly on materials that can be optimised to perform more than one function. High-throughput and combinatorial methodologies are being used more frequently to discover and design improved materials in a time efficient manner for a variety of applications. A number of technological challenges involve the field of electrochemistry, such as battery development, electrocatalysis, photocatalysis, corrosion protection, sensor development, photovoltaics and light-emitting materials. This review focuses on the utilisation of high-throughput and combinatorial methods that have incorporated, or are associated with, electrochemical methods. In many cases electrochemical determinations are well-suited for high-throughput methodologies, enabling direct quantitative analysis of properties. However, in other circumstances electrochemical measurements are complicated by additional factors. Hence the limitations of high-throughput and combinatorial electrochemistry are also discussed within.

Copper surface coatings produced by the cold spray process have been simulated by means of a two-dimensional computer simulation and compared with experimental data in terms of their porosity. During cold spray, solid state powders containing micrometer-sized particles are accelerated to supersonic velocities and fired onto a substrate, whereupon they undergo plastic deformation and subsequently adhere. Many factors may determine the resultant coating properties, among which include the particle size distribution, velocity, stagnation temperature, and pressure. The approach taken herein differs from those traditionally employed for modeling particle deformations and the subsequent formation of a surface coating. Such approaches rely heavily on the distribution of kinetic energy, elasticity, and fluidity of particles impacting the surface. Consequently, they are computationally impractical to simulate a bulk sample with statistical distributions of particle shape, size, and various experimental conditions. Rather than modeling the physical processes involved in particle deformations, our approach relies on correlating empirical and phenomenological statistical relationships of particle sizes and velocities obtained from experimental data to simulate coatings several hundreds of micrometers thick. In doing so, it enables the porosity of the coating to be related to both the temperature and particle size of the cold spray powders.