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International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

International audience ; Exposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing.

This paper provides an overview of the physical vapor technologies used to synthesize Cu2ZnSn(S,Se)4 thin films as absorber layers for photovoltaic applications. Through the years, CZT(S,Se) thin films have been fabricated using sequential stacking or co-sputtering of precursors as well as using sequential or co-evaporation of elemental sources, leading to high-efficient solar cells. In addition, pulsed laser deposition of composite targets and monograin growth by the molten salt method were developed as alternative methods for kesterite layers deposition. This review presents the growing increase of the kesterite-based solar cell efficiencies achieved over the recent years. A historical description of the main issues limiting this efficiency and of the experimental pathways designed to prevent or limit these issues is provided and discussed as well. Afinal section is dedicated to the description of promising process steps aiming at further improvements of solar cell efficiency, such as alkali doping and bandgap grading ; 1. R Caballero and M León acknowledge financial support via the Spanish Ministry of Science, Innovation and Universities project (WINCOST, ENE2016-80788-C5-2-R) and thank H2020 EU Programme under the project INFINITE-CELL (H2020-MSCA-RISE-2017-777968). 2. S Canulescu and J Schou acknowledge the support from Innovation Fund Denmark. 3. D-H Kim acknowledges financial support via the DGIST R&D Program of the Ministry of Science and ICT, KOREA (18-BD-05). 4.C. Malerba acknowledges the support from the Italian Ministry of Economic development in the framework of the Operating Agreement with ENEA for the Research on the Electric System. 5.A Redinger acknowledges financial support via the FNR Attract program, Project : SUNSPOT, Nr.11244141. 6. E Saucedo thanks H2020 EU Programme under the projects STARCELL (H2020-NMBP-03-2016-720907) and INFINITE-CELL (H2020-MSCA-RISE-2017-777968), the Spanish Ministry of Science, Innovation and Universities for the IGNITE project (ENE2017-87671-C3-1-R), and the European Regional Development Funds (ERDF, FEDER Programa Competitivitat de Catalunya 2007–2013). IREC belong to the SEMS (Solar Energy Materials and Systems) Consolidated Research Group of the 'Generalitat de Catalunya' (Ref. 2017 SGR 862). 7. Taltech acknowledges financial support via the Estonian Ministry of Education and Research funding project IUT19-28 and the European Union Regional Development Fund, Project TK141. 8. B Vermang has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (Grant Agreement No 715027)

Hexagonal Aluminium nitride (h-AlN) is an important wide-bandgap semiconductor material which is conventionally fabricated by high temperature carbothermal reduction of alumina under toxic ammonia atmosphere. Here we report a simple, low cost and potentially scalable mechanochemical procedure for the green synthesis of nanostructured h-AlN from a powder mixture of Aluminium and melamine precursors. A combination of experimental and theoretical techniques has been employed to provide comprehensive mechanistic insights on the reactivity of melamine, solid state metalorganic interactions and the structural transformation of Al to h-AlN under non-equilibrium ball milling conditions. The results reveal that melamine is adsorbed through the amine groups on the Aluminium surface due to the long-range van der Waals forces. The high energy provided by milling leads to the deammoniation of melamine at the initial stages followed by the polymerization and formation of a carbon nitride network, by the decomposition of the amine groups and, finally, by the subsequent diffusion of nitrogen into the Aluminium structure to form h-AlN. ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation - Flanders (FWO) and the Flemish Government – department EWI.