The carbon nitride poly(heptazine imide), PHI, has recently emerged as a powerful 2D carbon nitride photocatalyst with intriguing charge storing ability. Yet, insights into how morphology, particle size and defects influence its photophysical properties are virtually absent. Here, ultrasonication is used to systematically tune the particle size as well as concentration of surface functional groups and study their impact. Enhanced photocatalytic activity correlates with an optimal amount of those defects that create shallow trap states in the optical band gap, promoting charge percolation, as evidenced by time-resolved photoluminescence spectroscopy, charge transport studies, and quantum-chemical calculations. Excessive amounts of terminal defects can act as recombination centers and hence, decrease the photocatalytic activity for hydrogen evolution. Re-agglomeration of small particles can, however, partially restore the photocatalytic activity. The type and amount of trap states at the surface can also influence the deposition of the co-catalyst Pt, which is used in hydrogen evolution experiments. Optimized conditions entail improved Pt distribution, as well as an enhanced wettability and colloidal stability. A description of the interplay between these effects is provided to obtain a holistic picture of the size–property–activity relationship in nanoparticulate PHI-type carbon nitrides that can likely be generalized to related photocatalytic systems.<br>

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Ausgehend von Henri Lefebvre und Paul Ricoeur entwickelt Julia Kröger eine Raumtheorie, die eine Neubewertung der (Re)Konstruktionen von Paris im Naturalismus Émile Zolas erlaubt. Um den Prozess von der Dokumentation hin zur literarischen Fiktion in seinen unterschiedlichen Stufen nachvollziehen zu können, untersucht sie neben ausgewählten Romanen auch die Arbeitsbücher des Schriftstellers und Journalisten. Dabei wird deutlich, inwiefern in Zolas Darstellungen des Stadtraums schon zahlreiche Aspekte jener urbanen Moderne vorweggenommen wurden, die bisher vor allem Texten und Theorien des 20. Jahrhunderts zugeschrieben werden.

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