tet.folio: Eine Online-Plattform für die Produktion innovativer Lehr-Lern-Angebote

Als "Technology Enhanced Textbook", dem "Schulbuch der Zukunft" sowie als Verteilplattform für Interaktive Bildschirmexperimente (IBE) hat sich tet.folio in den letzten 10 Jahren zu einer universell einsetzbaren Lehr-Lern-Plattform entwickelt. Nach einer Übersicht interaktiver Beispiele aus unterschiedlichsten Fachgebieten stellen wir das Potential von tet.folio als Plattform für Autorinnen und Autoren vor. Basierend auf einfachen Konzepten werden mit tet.folio einheitlich erscheinende Lehr-Lern-Angebote umsetzbar. Effektiv herstellbar sind mit tet.folio neben individualisierten Inhalten auch entsprechende Formatvorlagen, mit denen Autorinnen und Autoren einheitlich gestaltete Lehr-Lern-Angebote schnell umsetzen können. Eine ansprechende Gestaltung der Angebote unterstützt die Fokussierung auf Lerninhalte. Die so erstellten Inhalte können, wenn gewünscht, auch als PDF im DIN-A4 Format oder für den Offline-Einsatz exportiert werden

At Least 10-fold Higher Lubricity of Molecularly Thin D2O vs H2O Films at Single-Layer Graphene−Mica Interfaces

Interfacial water is a widespread lubricant down to the nanometer scale. We investigate the lubricities of molecularly thin H2O and D2O films confined between mica and graphene, via the relaxation of initially applied strain in graphene employing Raman spectroscopy. Surprisingly, the D2O films are at least 1 order of magnitude more lubricant than H2O films, despite the similar bulk viscosities of the two liquids. We propose a mechanism based on the known selective permeation of protons vs deuterons through graphene. Permeated protons and left behind hydroxides may form ion pairs clamping across the graphene sheet and thereby hindering the graphene from sliding on the water layer. This explains the lower lubricity but also the hindering diffusivity of the water layer, which yields a high effective viscosity in accordance with findings in dewetting experiments. Our work elucidates an unexpected effect and provides clues to the behavior of graphene on hydrous surfaces.Peer Reviewe

Nanotubular J-Aggregates and Quantum Dots Coupled for Efficient Resonance Excitation Energy Transfer

Resonant coupling between distinct excitons in organic supramolecular assemblies and inorganic semiconductors is supposed to offer an approach to optoelectronic devices. Here, we report on colloidal nanohybrids consisting of self-assembled tubular J-aggregates decorated with semiconductor quantum dots (QDs) <i>via</i> electrostatic self-assembly. The role of QDs in the energy transfer process can be switched from a donor to an acceptor by tuning its size and thereby the excitonic transition energy while keeping the chemistry unaltered. QDs are located within a close distance (<4 nm) to the J-aggregate surface, without harming the tubular structures and optical properties of J-aggregates. The close proximity of J-aggregates and QDs allows the strong excitation energy transfer coupling, which is around 92% in the case of energy transfer from the QD donor to the J-aggregate acceptor and approximately 20% in the reverse case. This system provides a model of an organic–inorganic light-harvesting complex using methods of self-assembly in aqueous solution, and it highlights a route toward hierarchical synthesis of structurally well-defined supramolecular objects with advanced functionality