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Microplastics are a widespread contaminant found not only in various natural habitats but also in drinking waters. With spectroscopic methods, the polymer type, number, size, and size distribution as well as the shape of microplastic particles in waters can be determined, which is of great relevance to toxicological studies. Methods used in studies so far show a huge diversity regarding experimental setups and often a lack of certain quality assurance aspects. To overcome these problems, this critical review and consensus paper of 12 European analytical laboratories and institutions, dealing with microplastic particle identification and quantification with spectroscopic methods, gives guidance toward harmonized microplastic particle analysis in clean waters. The aims of this paper are to (i) improve the reliability of microplastic analysis, (ii) facilitate and improve the planning of sample preparation and microplastic detection, and (iii) provide a better understanding regarding the evaluation of already existing studies. With these aims, we hope to make an important step toward harmonization of microplastic particle analysis in clean water samples and, thus, allow the comparability of results obtained in different studies by using similar or harmonized methods. Clean water samples, for the purpose of this paper, are considered to comprise all water samples with low matrix content, in particular drinking, tap, and bottled water, but also other water types such as clean freshwater., B. E. Oßmann thanks the Bavarian State Ministry of the Environment and Consumer Protection for funding the projects “Detection of microplastics in selected foods” and “Expansion of the analytics of microplastics in food.” S. Lacorte acknowledges funding from the Ministry of Science and Innovation of Spain (project PID2019-105732GB-C21). J. Weisser, K. Glas, T. Hofmann, N. P. Ivleva, and E. von der Esch receive funding from the Bavarian Research Foundation (Bayerische Forschungsstiftung (BFS), AZ-1258-16 (“MiPAq”). N. P. Ivleva thanks the Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung (BMBF), projects 02WPL1443A “SubμTrack” and 03F0851B “HOTMIC”) for financial support. D. Fischer and F. Fischer acknowledge funding from the projects MicroCatch_Balt, PLASTRAT, PLAWES by the BMBF in the call “Plastics in the environment,” as well as from the BONUS BLUE BALTIC project MICROPOLL, which has received funding from BONUS (Art 185), funded jointly by the EU and the BMBF. N. Zumbülte and C. S. Witzig acknowledge funding by the BMBF of the project “MicBin.”

Microplastics in food is a relatively new research field with only few studies available so far. Scientists have been pointing out that some of these studies apply questionable analytical methods. Nevertheless, media often use such results to gain attention of the readers. It is therefore of particular significance, that only those scientific studies are published, clearly presenting valid data on the content of microplastics in food. Unfortunately, the study by Zuccarello et al. shows very critical aspects regarding analytical methods used and conclusions made. The applied procedure is not described and, therefore, does not allow any assessment by other groups, which is indispensable prerequisite of any scientific publication. Moreover, the analytical method used for the identification and quantification of microplastic particles – SEM-EDX – is not sound and not validated. Therefore, in our opinion the results on the contamination of bottled mineral water with microplastics published by Zuccarello et al. are more than questionable.

Conventional methods for wettability assessment are based on volumetric measurements such as displacement tests, and have to be modified for shales because of their low porosity, ultra low permeability with natural fractures, and reactive components. These methods are time consuming and the results are often questionable; these facts that have motivated the search for new approaches to estimate this property. A methodology for measuring shales wettability that uses X-Ray Photoelectron Spectroscopy (XPS) is presented in this paper. Results are compared with conventional imbibition tests. XPS is being used as a faster way to infer the wetting condition on sandstones rocks. XPS allows knowing the chemical composition of the outer layers of a solid surface. Using XPS the organic carbon content at the surface is evaluated, and then it is correlated with the wetting condition from imbibition tests. Water wet and oil wet shales from different countries were investigated. Samples were prepared rigorously for mineralogical and XPS measurement. The relationship between wettability and surface composition as determined from XPS is reported. Wettability index measured by imbibition tests is used in this study as an indicator of the wettability of shales. The XPS spectra of oil-wet surfaces of shales reveal the existence of organic carbon and also of an organic mineral species such as Si–CH. These species have a well-defined binding energy which differs from the inorganic species of mineral grains. In this study we present quantifiable evidence that chemisorbed organic material on the surfaces defines the oil-wetting character of oil shales. In the case of gas shales gas is adsorbed onto clay surfaces, as well in natural fractures and porous giving them oil wet condition. This view is supported by a strong correlation between the organic matter content on shale surfaces, the mineral composition and the wettability. In this paper we demonstrate a different approach for measuring shale wettability using XPS analysis. Instead of waiting for many days for the results from imbibition test, XPS takes less than one day. As a result, the time needed for the wettability measurement is reduced significantly.

The selective emitter formation by laser doping is a well known process to increase the efficiency of silicon solar cells [1] , [2] . For the characterization of laser doped emitters, SIMS (Secondary Ion Mass Spectroscopy) and ECV (Electrochemical Capacitance Voltage Measurement) techniques are used to analyze the emitter profile [3] . It is very difficult to get acceptable result by SIMS on a textured surface, so only ECV can be used. It has been shown, that a charge carrier depth profile can be measured on a homogeneous emitter only by ECV. The use of laser doping results in a non-homogeneous emitter. We have shown that the emitter depth is not just a function of the pulse power, but in addition of the surface structure of the wafer. The texture seems responsible for a strong variability in the doping profile. It has been shown, that the ECV measurement is not applicable to characterize the emitter depth on laser doped areas, because of the microscopic inhomogeneities in the emitter on the macroscopic measurement area. The real emitter profiles are to complex to be characterized by SIMS or ECV. We have shown that the variation in the emitter profile is resulting from the texture in the laser-doped regions.

New materials are of key importance for scaling memories in the sub 50 nm generations. Currently high-k materials and metal gates are investigated for usage in Flash and DRAM memory. However, the requirements in the applications are different, leading to different material combinations. This paper gives an overview on new materials with focus on memory applications.