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Ag thin films are widely used in Low-E glass. High conductivity and low emissivity require a film thickness of at least 10 nm, which is costly for the industry. The cost of Low-E coating could be drastically reduced by lowering the amount of Ag without decreasing the conductivity. For that purpose, it is necessary to understand Ag film growth and related macroscopic properties. This can be studied by thin film growth simulations. In this work, we present results of Ag growth on ZnO by magnetron sputtering and related properties with multiscale simulations (DFT, Molecular Dynamics, and kinetic Monte Carlo). A new method to take into account defects generated by magnetron sputtering has been developed. Simulated conductivity has been compared with experiments and shows the same trend with a difference attributed to electron scattering at grain boundaries. To go further, we propose patterned substrates with and without defects to find an original tuneable process to increase the conductivity of ultrathin metallic films. We show that a patterned substrate does not increase the conductivity. Instead, it leads to a controlled growth of small islands which could be used for other applications requiring plasmonic properties. Finally, conductivity is higher for the same deposited thickness when the substrate has a higher defect density.

Graphdiyne (GDY), which features a highly π-conjugated structure, direct bandgap, and high charge carrier mobility, presents the major requirements for photocatalysis. Up to now, all photocatalytic studies are performed without paying too much attention on the GDY bandgap (1.1 eV at the GW many-body theory level). Such a narrow bandgap is not suitable for the band alignment between GDY and other semiconductors, making it difficult to achieve efficient photogenerated charge carrier separation. Herein, for the first time, it is demonstrated that tuning the electronic bandgap of GDY via H-substitution (H-GDY) promotes interfacial charge separation and improves photocatalytic H evolution. The H-GDY exhibits an increased bandgap energy (≈2.5 eV) and exploitable conduction band minimum and valence band maximum edges. As a representative semiconductor, TiO is hybridized with both H-GDY and GDY to fabricate a heterojunction. Compared to the GDY/TiO, the H-GDY/TiO heterojunction leads to a remarkable enhancement of the photocatalytic H generation by 1.35 times under UV–visible illumination (6200 µmol h g) and four times under visible light (670 µmol h g). Such enhancement is attributed to the suitable band alignment between H-GDY and TiO, which efficiently promotes the photogenerated electron and hole separation, as supported by density functional theory calculations., The work in Mons was supported by the Belgian National Fund for Scientific Research (FRS-FNRS). Computational resources were provided by the Consortium des Équipements de Calcul Intensif (CÉCI) funded by F.R.S.-FNRS under Grant No. 2.5020.11. J.C. is an FNRS research director. ICN2 acknowledges funding from Generalitat de Catalunya 2017 SGR 327 and the Spanish MINECO project ENE2017-85087-C3. ICN2 was supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and was funded by the CERCA Programme/Generalitat de Catalunya. Part of the present work was performed in the framework of Universitat Autònoma de Barcelona Materials Science Ph.D. program. X.H. thanks China Scholarship Council for scholarship support (201804910551).

International audience; The rapidly growing interest in carbohydrate-based bioactive molecules calls for strategies enabling the appropriate design and large-scale delivery of the glycan moiety. Herein, we describe the robust and high-yielding chemical synthesis of an orthogonally-protected pentasaccharide intended for use as a central building block in vaccine development against Shigella flexneri 3a. Elaborated from advanced crystalline intermediates and fine-tuned catalytic processes facilitating regio-and stereoselective conversions, a robust [2 + 3] strategy was designed, which avoided several tedious purifications and efficiently delivered multigram amounts of the target pentasaccharide. Conversion of this intermediate into a donor and a linker-equipped acceptor then merging then into the frame of a [5 + 5] glycosylation step furnished a decasaccharide encompassing one trichloroacetamide moiety per repeat. Chemoselective delevulination and subsequent Pd(OH) 2-mediated hydrogenolysis enabling concomitant hydrodechlorination and azide reduction gave the ready-for-conjugation dimer of the repeating unit of the O-antigen from S. flexneri 3a featuring the natural stoichiometric O-acetylation. The proof-of-concept was established, opening the way to larger S. flexneri 3a oligosaccharides and fine-tuned glycoconjugates.

Effective methods for the synthesis of high-purity nanoparticles (NPs) have been extensively studied for a few decades. Among others, cold plasma-based sputtering metals onto a liquid substrate appears to be a very promising technique for the synthesis of high-purity NPs. The process enables the production of very small NPs without using any toxic reagents and complex chemical synthesis routes, and enables the synthesis of alloy NPs which can be the first step towards the formation of porous NPs. In this paper, the synthesis of gold-copper alloy NPs has been performed by co-sputtering gold and copper targets over pentaerythritol ethoxylate. The resulting solutions contain a mixture of gold, copper oxide, and alloy NPs having a radius of few angstroms. The annealing of these NPs, inside the solution, has been performed in order to increase their size and further induce the dealloying of the Au-Cu NPs. The resulting NPs exhibit either a nanoporous structure or are self-organized in an agglomerate of small NPs.

Low-emissivity glasses rely on multistacked architectures with a thin silver layer sandwiched between oxide layers. The mechanical stability of the silver/oxide interfaces is a critical parameter that must be maximized. Here, we demonstrate by means of quantum-chemical calculations that a low work of adhesion at interfaces can be significantly increased via doping and by introducing vacancies in the oxide layer. For the sake of illustration, we focus on the ZrO2(111)/Ag(111) interface exhibiting a poor adhesion in the pristine state and quantify the impact of introducing n-type dopants or p-type dopants in ZrO2 and vacancies in oxygen atoms (nVO; with n = 1, 2, 4, 8, 10, 16), zirconium atoms (mVZr; with m = 1, 2, 4, 8), or both (nVO + mVZr; with m/n = 1:2, 1:4, 2:2, 2:4). In the case of doping, interfacial electron transfer promotes an increase in the work of adhesion, from initially 0.16 to ∼0.8 J m-2 (n-type) and ∼2.0 J m-2 (p-type) at 10% doping. A similar increase in the work of adhesion is obtained by introducing vacancies, e.g., VO [VZr] in the oxide layer yields a work of adhesion of ∼1.5-2.0 J m-2 at 10% vacancies. An increase is also observed when mixing VO and VZr vacancies in a nonstoichiometric ratio (nVO + mVZr; with 2n ≠ m), while a stoichiometric ratio of VO and VZr has no impact on the interfacial properties.

We describe the modification of the work function (WF) of Au(111) upon deposition of self-assembled monolayers (SAMs) with two donor–acceptor (D–A) systems, one based on a ferrocene-polychlorotriphenylmethyl radical (Fc–PTM) dyad and another on its non-radical dyad analogue. Kelvin Probe Force Microscopy (KPFM) has been used to measure the changes in the Contact Potential Difference (CPD) between the tip and the SAM under application of a cycling sweep of direct current (DC) voltage bias. These measurements showed that both SAMs exhibit a hysteretic behaviour in their WF changes. Interestingly, the hysteresis loop of the radical SAM is notably reduced when irradiated with NIR light, which we attribute to the bistable nature of this SAM in which neutral radical dyad molecules are excited into a zwitterionic state following a light driven intramolecular charge transfer (ICT) from the Fc unit to the PTM radical unit. Consequently, under NIR irradiation the WF hysteresis is almost quenched and the WF value of the functionalized gold surface is significantly shifted by +250 mV recovering their original values when the irradiation is suppressed. Remarkable is the large WF shift attained, one of the highest values reported in the literature, and the unprecedented fact that it is achieved under irradiation in the IR region due to an intramolecular electronic reorganization. In contrast, the WF value and the WF hysteresis of the non-radical SAM does not change upon NIR irradiation since this SAM does not display bistability., This work was financially supported by the EC through the Marie Curie project ITN iSwitch (GA no. 642196). Computational resources were provided by the Consortium des Équipements de Calcul Intensif (CÉCI) funded by the Belgian National Fund for Scientific Research (F.R.S.-FNRS) under Grant 2.5020.11. J. C. is an FNRS research director. The authors also acknowledge the financial support from Instituto de Salud Carlos III, through “Acciones CIBER.” The Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), an initiative funded by the VI National R&D&I Plan 2008–2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. The authors also appreciate the financial support through projects: FANCY (CTQ2016-80030-R), and MOTHER (MAT2016-80826-R), granted by DGI (Spain), GenCat (2017 SGR 918), financed by DGR (Catalunya), and Severo Ochoa Program Grant SEV-2015-0496, financed by Mineco (Spain)., We acknowledge support of the publication fee by the CSIC Open Access Support Initiative through its Unit of Information Resources for Research (URICI)

6 Figuras. 3 Tablas., The effect of doping on the electronic properties in bulk single-walled carbon nanotube (SWCNT) samples is studied for the first time using a new in situ Raman spectroelectrochemical method, and further verified by DFT calculations and photoresponse. We use p-/n-doped SWCNTs prepared by diazonium reactions as a versatile chemical strategy to control the SWCNT behavior. The measured and calculated data testify an acceptor effect of 4-aminobenzenesulfonic acid (p-doping), and a donor effect (n-doping) in the case of benzyl alcohol. In addition, pristine and covalently functionalized SWCNTs were used for the preparation of photoactive film electrodes. The photocathodic current in the photoelectrochemical cell is consistently modulated by the doping group. These results validate the in situ Raman spectroelectrochemistry as a unique tool box for predicting the electronic properties of functionalized SWCNTs in the form of thin films and their operational functionality in thin film devices for future optoelectronic applications., The authors acknowledge financial support from the European Union FP7 RADDEL programme (ITN Marie Curie Actions PEOPLE-2011-290023) and the MEYS Inter Excellence Project no. LTC18039 and H2020-MSCA RISE Agreement no. 734834 (INFUSION). This work at the Instituto de Carboquímica has been funded by the MINECO and the European Regional Development Fund (ENE 2016-79282-C5-1-R), the Government of Aragon (T03-17R), and the European Commission (H2020-MSCA-ITN-2014-ETN 642742 ‘Enabling Excellence’). The work in Mons is supported by the European Union H2020 iSwitch programme (H2020-MSCA-ITN-2014-ETN 642196). Computational resources in Mons were provided by the Consortium des Équipements de Calcul Intensif (CÉCI) funded by the Belgian National Fund for Scientific Research (F.R.S.-FNRS) under Grant 2.5020.11. J. C. is an FNRS research director. The authors acknowledge the assistance provided by the Research Infrastructures NanoEnviCz (Project No. LM2015073) supported by the Ministry of Education, Youth and Sports of the Czech Republic and the project Pro-NanoEnviCz (Reg. no. CZ.02.1.01/0.0/0.0/16_013/0001821) supported by the Ministry of Education, Youth and Sports of the Czech Republic and the European Union – European Structural and Investments Funds in the frame of Operational Programme Research Development and Education. J. M. G.-D. is grateful to Spanish Ministry of Science, Innovation and Universities for his ‘Juan de la Cierva – Incorporación’ research grant. A. S. is grateful to Dr Sara Costa and Dr Johan Ek Weis for fruitful discussions and helpful comments., We also acknowledge institutional support from the Unit of Information Resources for Research at the "Consejo Superior de Investigaciones Científicas" (CSIC) for the article-processing charges contribution