The structure of the ionic liquid / electrode interface and its possible influence on electrochemical materials synthesis: an in situ STM and AFM Study

Ionic liquids (ILs) have become one of the most popular material classes over the past twenty years. They have been considered as alternative materials to molecular solvents and molten salts in various applications (e.g. batteries, capacitors, lubricants, solvents for electrodeposition purposes). A detailed understanding of the IL/solid interfacial nanostructure and of the spatial distribution of the electroactive species at the interface is important for the development of various technical processes using ILs. In the present work the structure of the electrified IL/solid interface was investigated using in situ scanning tunnelling microscopy (STM) and atomic force microscopy (AFM). Various ILs, namely [Py1,4]TFSA, [Py1,4]FAP, [Py1,4]FSA, [Py1,4]TfO, [EMIm]TFSA, [OMIm]TFSA, [EMIm]FAP, [EMIm]TfO and [HMIm]FAP were applied for this study. In situ AFM reveals that multiple interfacial layers are present at the IL/electrode interface. Furthermore, the applied potential determines whether cations or anions are preferably adsorbed to the substrate with stronger near surface layering detected at higher positive or negative surface potentials. Both the cation and the anion of the IL have a strong influence on the structure and composition of the interface. In situ STM shows that the appearance of the Au(111) and H-terminated p-Si(111) surfaces is different in various ILs, due to specific ion/surface and ion/ion interactions, which are dependent on the type of the functional groups (pyrrolidinium or imidazolium ring and the length of the alkyl chains), resulting in a different interfacial structure for various cations. With the same anion, the Au(111) surface undergoes the (22 x √3) reconstruction with [Py1,4]+ during cathodic polarization, but with [EMIm]+, [HMIm]+ and [OMIm]+ the herringbone superstructure has not been obtained. Furthermore, different [OMIm]TFSA superstructures with the lateral size between 1.2 and 1.7 nm are probed with in situ STM on highly ordered pyrolytic graphite (HOPG) at high negative electrode potentials, as a result of several cation and/or anion layers probed at the same time by the STM tip. AFM measurements show that the imidazolium cation is adsorbed at the H-Si(111)/[EMIm]TFSA interface leading to an ordered clustered facet structure of ~3.8 nm in size. In comparison, the Si(111)/[Py1,4]TFSA interface appears the same as the native surface under argon. The interfacial structure is sensitive to metal and semiconductor salts dissolved in the IL. In general the ion layering at the IL/solid interface is markedly different in the presence of dissolved solutes than for the pure IL systems, as the presence of salt ions alters both the IL-surface and IL-IL interactions at the interface. For instance, AFM measurements reveal that interfacial layering is markedly weaker in the presence of LiCl and SiCl4 in [Py1,4]FAP. The presence of Li+ and Si(IV) affects interactions between [Py1,4]+ and the gold surface hindering the (22 x √3) Au(111) reconstruction. Marked changes in the IL/Si(111) interfacial structure are obtained on addition of LiTFSA in [Py1,4]TFSA and [EMIm]TFSA. The concentration of the solute has also a significant effect on the structure of the IL/electrode interface. Thus, considerable changes are obtained on addition of high concentrations of NaFSA and LiTFSA in [Py1,4]FSA and [Py1,4]TFSA, respectively. For the [EMIm]TfO/Au(111) interface the structure of the innermost layer also depends on the amount of added water. A transition from a multilayered structure to a classical double layer structure occurs at -1.0 V vs. Pt on changing the water concentration from 30 to 50 vol%. The formation of a double layer structure at the IL/Au(111) interface is also obtained on increasing the concentration of SiCl4 in [Py1,4]FAP. In situ AFM force-separation measurements confirm that the dissolved solute is present within the innermost (Stern) layer. The altered interfacial structures represent the best compromise between the IL ion and solute surface affinities, packing constraints, and charge localisations. Thus, the IL EDL is highly complex both in the pure ILs and in the presence of solutes and often leads to an unpredictable electrochemical behaviour. This in turn should affect the reactions that occur at the IL/electrode interface (e.g. metal deposition). Thus, in [Py1,4]TFSA, TaF5 can be reduced to elemental Ta, while in [Py1,4]FAP the electroreduction processes are practically inhibited. The difference for Si deposition from SiCl4 in [Py1,4]TFSA and [Py1,4]FAP is roughly 1 V. The crystal sizes of the electrodeposited Ga varies upon changing the ILs. The deposit made from [Py1,4]TFSA consists of spherical structures of 60-260 nm in diameter, while the crystal sizes of a Ga deposit obtained from [Py1,4]TfO are between 15 and 110 nm. In the case of [Py1,4]FSA a nanocrystalline Ga deposit with a crystal size of less than 50 nm is obtained. Furthermore, GaSb obtained in [EMIm]TFSA and [Py1,4]TFSA exhibits a band gap of about 1.2 eV and 0.9 eV, respectively. The present work shows that the electrodeposition of metals and semiconductors in ILs is complicated. On the one hand, the (chemical) structure of the IL has an influence on the EDL structure of the Au(111)/IL interface. On the other hand, the addition of precursors, which are required for the deposition processes, can also affect the structure of the electrode/IL interface. Furthermore, the nanostructure of interfacial layers can vary if the concentration of the precursor is increased, which might facilitate the deposition processes. Such interfacial effects have to be considered for all applications that involve reactions at the IL/solid interface

Electrodeposition of zinc nanoplates from an ionic liquid composed of 1-butylpyrrolidine and ZnCl2: electrochemical, in situ AFM and spectroscopic studies

The mixtures of 1-butylpyrrolidine and ZnCl2 result in the formation of an ionic liquid, which can be used as an electrolyte for zinc electrodeposition. The feasibility of electrodepositing Zn from these electrolytes was investigated at RT and at 60 °C. The synthesized mixtures are rather viscous. Toluene was added to the mixtures to decrease the viscosity of the ILs. Vibrational spectroscopy was employed for the characterization of the liquids. The electrochemical behaviour of the liquids was evaluated by cyclic voltammetry. The electrode/electrolyte interface of this IL was probed by Atomic Force Microscopy (AFM). The suitable range for the electrodeposition of Zn was found to be ≥28.6 mol% of ZnCl2. Zn deposition occurs mainly from the cationic species of [ZnClxLy]+ (where x = 1, y = 1–2, and L = 1-butylpyrrolidine) in these electrolytes. This is in contrary to the well investigated chlorozincate ionic liquids where the deposition of Zn occurs mainly from anionic chlorozincates. Nanoplates of Zn were obtained from these mixtures of 1-butylpyrrolidine and ZnCl2

The Role of DNA Barcodes in Understanding and Conservation of Mammal Diversity in Southeast Asia

Southeast Asia is recognized as a region of very high biodiversity, much of which is currently at risk due to habitat loss and other threats. However, many aspects of this diversity, even for relatively well-known groups such as mammals, are poorly known, limiting ability to develop conservation plans. This study examines the value of DNA barcodes, sequences of the mitochondrial COI gene, to enhance understanding of mammalian diversity in the region and hence to aid conservation planning.DNA barcodes were obtained from nearly 1900 specimens representing 165 recognized species of bats. All morphologically or acoustically distinct species, based on classical taxonomy, could be discriminated with DNA barcodes except four closely allied species pairs. Many currently recognized species contained multiple barcode lineages, often with deep divergence suggesting unrecognized species. In addition, most widespread species showed substantial genetic differentiation across their distributions. Our results suggest that mammal species richness within the region may be underestimated by at least 50%, and there are higher levels of endemism and greater intra-specific population structure than previously recognized.DNA barcodes can aid conservation and research by assisting field workers in identifying species, by helping taxonomists determine species groups needing more detailed analysis, and by facilitating the recognition of the appropriate units and scales for conservation planning

A reference library for Canadian invertebrates with 1.5 million barcodes, voucher specimens, and DNA samples

The synthesis of this dataset was enabled by funding from the Canada Foundation for Innovation, from Genome Canada through Ontario Genomics, from NSERC, and from the Ontario Ministry of Research, Innovation and Science in support of the International Barcode of Life project. It was also enabled by philanthropic support from the Gordon and Betty Moore Foundation and from Ann McCain Evans and Chris Evans. The release of the data on GGBN was supported by a GGBN – Global Genome Initiative Award and we thank G. Droege, L. Loo, K. Barker, and J. Coddington for their support. Our work depended heavily on the analytical capabilities of the Barcode of Life Data Systems (BOLD, www.boldsystems.org). We also thank colleagues at the CBG for their support, including S. Adamowicz, S. Bateson, E. Berzitis, V. Breton, V. Campbell, A. Castillo, C. Christopoulos, J. Cossey, C. Gallant, J. Gleason, R. Gwiazdowski, M. Hajibabaei, R. Hanner, K. Hough, P. Janetta, A. Pawlowski, S. Pedersen, J. Robertson, D. Roes, K. Seidle, M. A. Smith, B. St. Jacques, A. Stoneham, J. Stahlhut, R. Tabone, J.Topan, S. Walker, and C. Wei. For bioblitz-related assistance, we are grateful to D. Ireland, D. Metsger, A. Guidotti, J. Quinn and other members of Bioblitz Canada and Ontario Bioblitz. For our work in Canada’s national parks, we thank S. Woodley and J. Waithaka for their lead role in organizing permits and for the many Parks Canada staff who facilitated specimen collections, including M. Allen, D. Amirault-Langlais, J. Bastick, C. Belanger, C. Bergman, J.-F. Bisaillon, S. Boyle, J. Bridgland, S. Butland, L. Cabrera, R. Chapman, J. Chisholm, B. Chruszcz, D. Crossland, H. Dempsey, N. Denommee, T. Dobbie, C. Drake, J. Feltham, A. Forshner, K. Forster, S. Frey, L. Gardiner, P. Giroux, T. Golumbia, D. Guedo, N. Guujaaw, S. Hairsine, E. Hansen, C. Harpur, S. Hayes, J. Hofman, S. Irwin, B. Johnston, V. Kafa, N. Kang, P. Langan, P. Lawn, M. Mahy, D. Masse, D. Mazerolle, C. McCarthy, I. McDonald, J. McIntosh, C. McKillop, V. Minelga, C. Ouimet, S. Parker, N. Perry, J. Piccin, A. Promaine, P. Roy, M. Savoie, D. Sigouin, P. Sinkins, R. Sissons, C. Smith, R. Smith, H. Stewart, G. Sundbo, D. Tate, R. Tompson, E. Tremblay, Y. Troutet, K. Tulk, J. Van Wieren, C. Vance, G. Walker, D. Whitaker, C. White, R. Wissink, C. Wong, and Y. Zharikov. For our work near Canada’s ports in Vancouver, Toronto, Montreal, and Halifax, we thank R. Worcester, A. Chreston, M. Larrivee, and T. Zemlak, respectively. Many other organizations improved coverage in the reference library by providing access to specimens – they included the Canadian National Collection of Insects, Arachnids and Nematodes, Smithsonian Institution’s National Museum of Natural History, the Canadian Museum of Nature, the University of Guelph Insect Collection, the Royal British Columbia Museum, the Royal Ontario Museum, the Pacifc Forestry Centre, the Northern Forestry Centre, the Lyman Entomological Museum, the Churchill Northern Studies Centre, and rare Charitable Research Reserve. We also thank the many taxonomic specialists who identifed specimens, including A. Borkent, B. Brown, M. Buck, C. Carr, T. Ekrem, J. Fernandez Triana, C. Guppy, K. Heller, J. Huber, L. Jacobus, J. Kjaerandsen, J. Klimaszewski, D. Lafontaine, J-F. Landry, G. Martin, A. Nicolai, D. Porco, H. Proctor, D. Quicke, J. Savage, B. C. Schmidt, M. Sharkey, A. Smith, E. Stur, A. Tomas, J. Webb, N. Woodley, and X. Zhou. We also thank K. Kerr and T. Mason for facilitating collections at Toronto Zoo and D. Iles for servicing the trap at Wapusk National Park. This paper contributes to the University of Guelph’s Food from Thought research program supported by the Canada First Research Excellence Fund. The Barcode of Life Data System (BOLD; www.boldsystems.org)8 was used as the primary workbench for creating, storing, analyzing, and validating the specimen and sequence records and the associated data resources48. The BOLD platform has a private, password-protected workbench for the steps from specimen data entry to data validation (see details in Data Records), and a public data portal for the release of data in various formats. The latter is accessible through an API (http://www.boldsystems.org/index.php/resources/api?type=webservices) that can also be controlled through R75 with the package ‘bold’76.Peer reviewedPublisher PD

Proliferating activity in a bryozoan lophophore

Bryozoans are small benthic colonial animals; their colonies consist of zooids which are composed of a cystid and polypide. According to morphological and molecular data, three classes of bryozoans are recognized: Phylactolaemata, Gymnolaemata and Stenolaemata. Bryozoans are active suspension feeders and their feeding apparatus, the lophophore, is fringed with a single row of ciliated tentacles. In gymnolaemates, the lophophore is bell-shaped and its tentacles may be equal in length (equitentacled lophophores) or some tentacles may be longer than others (obliquely truncated lophophores). In encrusting colonies, polypides with obliquely truncated lophophores usually border specific sites of excurrent water outlets (colony periphery and chimneys) where depleted water has to be removed. It is known that during colony astogeny, colony-wide water currents rearrange: new chimneys are formed and/or location of the chimneys within a given colony changes with time. Such rearrangement requires remodeling of the lophophore shape and lengthening of some tentacles in polypides surrounding water outlets. However, proliferating activity has not been described for bryozoans. Here, we compared the distribution of S-phase and mitotic cells in young and adult polypides in three species of Gymnolaemata. We tested the hypothesis that tentacle growth/elongation is intercalary and cell proliferation takes place somewhere at the lophophore base because such pattern does not interfere with the feeding process. We also present a detailed description of ultrastructure of two parts of the lophophore base: the oral region and ciliated pits, and uncover the possible function of the latter. The presence of stem cells within the ciliated pits and the oral region of polypides provide evidence that both sites participate in tentacle elongation. This confirms the suggested hypothesis about intercalary tentacle growth which provides a potential to alter a lophophore shape in adult polypides according to rearrangement of colony wide water currents during colony astogeny. For the first time deuterosome-like structures were revealed during kinetosome biogenesis in the prospective multiciliated epithelial cells in invertebrates. Tentacle regeneration experiments in Electra pilosa demonstrated that among all epidermal cell types, only non-ciliated cells at the abfrontal tentacle surface are responsible for wound healing. Ciliated cells on the frontal and lateral tentacle surfaces are specialized and unable to proliferate, not even under wound healing. Tentacle regeneration in E. pilosa is very slow and similar to the morphallaxis type. We suggest that damaged tentacles recover their length by a mechanism similar to normal growth, powered by proliferation of cells both within ciliated pits and the oral region

Influence of molecular organization of ionic liquids on electrochemical properties

Ionic liquids (IL) exhibit a remarkably diverse interfacial chemistry, with multiple interfacial layers present at the IL/solid interface. Ionic liquids (ILs) are pure salts with melting points typically less than 100°C. It has remarkable physical properties, which include wide electrochemical stability windows, high ionic conductivity and negligible vapor pressure. The adsorption strength of ILs onto solid surfaces is much higher than for typical organic solvents or water. The structure and composition of the interfacial layer can be tuned by varying the surface potential and the ionic structure, and by addition of solutes. This allows us to envision that IL interfacial properties can be readily matched to a particular application once the required fundamental understanding is elucidated. STM and AFM results show that the IL cation has a strong influence on the structure and composition of the interface

Formation of professional competencies of primary school teachers using ICT

The purpose of the publication is to publish the results of a study that reveals how the intensity of the use of ICT in educational activities affects the formation of professional competencies of primary education teachers. With this in mind, the aim of the study is to establish the role of ICT in shaping the online competencies of primary school teachers, to study the content of the competency based approach and the participation of social media platforms and software applications.  The object of this study is a complex of ICTs, which actively participates in the formation of competencies of teachers of primary education. The implementation of the objectives of the study requires a set of methods and theoretical analysis and synthesis, as well as methods of comparison, grouping and specification (determination of the research data on the formation of professional competencies of primary school teachers).  The results of the research were obtained through the use of qualitative studies (standard focus groups) with subsequent analysis and report preparation. The results of the analysis are used to determine the content and interaction of key and professional competencies in the field of primary education and the high level of use of ICT tools.  Almost 80% of students aged from 20 to24 used the use of Twitter, Telegram, Facebook in remote education during the academic year 2019/2020.The presented work concludes that the use of ICT, like social media platforms, software applications, software and messenger clouds, increases the level of online competence of teachers and expands the range of professional competencies. The constant modernization of educational content based on Twitter, Telegram, Facebook, etc. should be promising for the formation of key and professional competencies and strengthening motivation in the training of primary education teachers.O objetivo da publicação é divulgar os resultados de um estudo que revela como a intensidade da utilização das TIC nas atividades educativas afeta a formação das competências profissionais dosprofessores do ensino básico. Com isso em mente, o objetivo do estudo é estabelecer o papel das TIC na formação das competências online dos professores do ensino básico, para estudar o conteúdo da abordagem baseada nas competências e a participação das plataformas de redes sociais e aplicações de software. O objeto deste estudo é um complexo de TICs, que participa ativamente na formação de competências dos professores do ensino fundamental. A concretização dos objetivos do estudo requer um conjunto de métodos e análises teóricas e síntese, bem como métodos de comparação , agrupamento e especificação (determinação dos dados da investigação sobre a formação de competências profissionais dos professores do ensino básico). Os resultados da pesquisa foram obtidos por meio da utilização de estudos qualitativos (grupos de foco padrão) com posterior análise e elaboração de relatórios. Os resultados da análise são usados para determinar o conteúdo e a interação das competências essenciais e profissionais no campo da educação primária e o alto nível de uso de ferramentas de TIC. Quase 80% dos alunos de 20 a 24 anos utilizaram Twitter, Telegram, Facebook na educação à distância durante o ano letivo de 2019/2020. O trabalho apresentado conclui que o uso das TIC, como plataformas de redes sociais, aplicações de software, software e mensageiro nuvens, aumenta o nível de competência online dos professores e expande o leque de competências profissionais. A constante modernização dos conteúdos educacionais baseados no Twitter, Telegram, Facebook, etc. deve ser promissora para a formação de competências essenciais e profissionais e fortalecimento da motivação no formação de professores do ensino básico.El propósito de la publicación es dar a conocer los resultados de un estudio que revela cómo la intensidad del uso de las TIC en las actividades educativas incide en la formación de competencias profesionales de los docentes de Educación Primaria, teniendo en cuenta que el objetivo del estudio es establecer el papel de las TIC en la configuración de las competencias en línea de los maestros de escuela primaria, para estudiarel contenido del enfoque basado en competencias y la participación de plataformas de redes sociales y aplicaciones de software. El objeto de este estudio es un complejo de TIC, que participa activamente en la formación de competencias de los docentes de educación primaria.La implementación de los objetivos del estudio requiere de un conjunto de métodos y análisis y síntesis teóricos, así como métodos de comparación. , agrupación y especificación (determinación de los datos de investigación sobre la formación de competencias profesionales de los docentes de primaria). Los resultados de la investigación se obtuvieron mediante el uso de estudios cualitativos (grupos focales estándar) con posterior análisis y elaboración de informes, los resultados del análisisse utilizan para determinar el contenido y la interacción de competencias clave y profesionales en el ámbito de la educación primaria y el alto nivel de uso de herramientas TIC. Casi el 80% de los estudiantes de 20 a 24 años utilizaron Twitter, Telegram, Facebook en educación remota durante el año académico 2019/2020. El trabajo presentado concluye que el uso de las TIC, como plataformas de redes sociales, aplicaciones de software, software y mensajería nubes, aumenta el nivel de competencia online de los docentes y amplía el abanico de competencias profesionales La constante modernización de los contenidos educativos basados en Twitter, Telegram, Facebook, etc. debe ser prometedora para la formación de competencias clave y profesionales y el fortalecimiento de la motivación en la formación de profesores de educación primaria

Surface modification of battery electrodes via electroless deposition with improved performance for Na-ion batteries

Sodium-ion batteries (SIBs) are emerging as potential stationary energy storage devices due to the abundance and low cost of sodium. A simple and energy efficient strategy to develop electrodes for SIBs with a high charge/discharge rate is highly desirable. Here we demonstrate that by surface modification of Ge, using electroless deposition in SbCl3/ionic liquids, the stability and performance of the anode can be improved. This is due to the formation of GexSb1−x at the surface leading to better diffusion of Na, and the formation of a stable twin organic and inorganic SEI which protects the electrode. By judicious control of the surface modification, an improvement in the capacity to between 50% and 300% has been achieved at high current densities (0.83–8.4 A g−1) in an ionic liquid electrolyte NaFSI-[Py1,4]FSI. The results clearly demonstrate that an electroless deposition based surface modification strategy in ionic liquids offers exciting opportunities in developing superior energy storage devices