Molecular metal oxides, or polyoxometalates (POMs) offer unrivalled properties in areas ranging from catalysis and energy conversion through to molecular electronics, biomimetics and theranostics. While POMs are ubiquitous metal oxide model systems studied in most areas of chemistry and materials science, their technological deployment is often hampered by their molecular nature, as this leads to increased degradation, leaching and loss of reactivity, particularly when harsh applications, such as water electrolysis, thermal catalysis or highly basic/acidic reaction solutions are targeted. Therefore, immobilization of POMs on heterogeneous substrates has recently become a central theme in POM research. While early studies focused mainly on metal oxide and semiconductor supports, more recently, POM integration in soft matter matrices including polymers, conductive polymers, hydrogels and stimuliresponsive matrices have led to breakthroughs in multifunctional composite design. This Progress Report will summarize the recent pioneering studies in this emerging field, highlight current challenges which need to be overcome to allow a more widespread technological deployment and provide the authors' view of some of the most promising future directions of the research field. In addition, we provide an unprecedented summary of the correlations between structure (on the molecular, nano-and microscale) and resulting reactivity, so that materials design beyond empirical studies can be further developed. We believe that this timely Progress Report will serve as a focal point to further develop the field, as well as point of reference for newcomers in the area of knowledge-driven bottom up materials design. Given this broad range of interest groups, we believe that Advanced Functional Materials is the ideal journal for this Progress Report.

Polydehydroalanine (PDha) is a polyampholyte featuring both a –NH2 and a –COOH in every repeat unit and with that presents a rather high charge density. The synthesis and polymerization of two monomers, benzyl 2‐tert‐butoxycarbonylaminoacrylate and methyl 2‐benzyloxycarbonylaminoacrylate is herein reported, which feature different protective groups and, after polymerization, the resulting PtBABA and PBOMA can be transformed into PDha using polymer‐analogous modification reactions. More important, the current choice of protective groups allows either simultaneous deprotection in one step in both cases, but also the orthogonal deprotection of either –NH2 or –COOH moiety for PtBABA, given that appropriate conditions are chosen. The polymers are prepared using free radical polymerization and all (intermediate) polymeric materials are investigated using a combination of NMR spectroscopy and size exclusion chromatography.

Recently, porous photocatalytically active block copolymer membranes were introduced, based on heterogenized molecular catalysts. Here, we report the integration of the photosensitizer, i. e., the light absorbing unit in an intermolecular photocatalytic system into block copolymer membranes in a covalent manner. We study the resulting structure and evaluate the orientational mobility of the photosensitizer as integral part of the photocatalytic system in such membranes. To this end we utilize transient absorption anisotropy, highlighting the temporal reorienta-tion of the transition dipole moment probed in a femtosecond pump-probe experiment. Our findings indicate that the photosensitizer is rigidly bound to the polymer membrane and shows a large heterogeneity of absolute anisotropy values as a function of location probed within the matrix. This reflects the sample inhomogeneity arising from different protonation states of the photosensitizer and different intermolecular interactions of the photosensitizers within the block copolymer membrane scaffold.

Heterogeneous light-driven catalysis is a cornerstone of sustainable energy conversion. Most catalytic studies focus on bulk analyses of the hydrogen and oxygen evolved, which impede the correlation of matrix heterogeneities, molecular features, and bulk reactivity. Here, we report studies of a heterogenized catalyst/photosensitizer system using a polyoxometalate water oxidation catalyst and a model, molecular photosensitizer that were co-immobilized within a nanoporous block copolymer membrane. Via operando scanning electrochemical microscopy (SECM), light-induced oxygen evolution was determined using sodium peroxodisulfate (Na 2 S 2 O 8 ) as sacrificial electron acceptor. Ex situ element analyses provided spatially resolved information on the local concentration and distribution of the molecular components. Infrared attenuated total reflection (IR-ATR) studies of the modified membranes showed no degradation of the water oxidation catalyst under the reported light-driven conditions.

Die heterogene lichtgetriebene Katalyse ist ein Eckpfeiler nachhaltiger Energieumwandlung. Die meisten katalytischen Studien konzentrieren sich auf die Analyse von Wasserstoff und Sauerstoff, wobei in der Regel über die Gesamtantwort gemittelt wird, und somit eine Korrelation von Heterogenitäten der Matrix mit unterschiedlichen molekularen Aktivitäten limitiert ist. Hier berichten wir von Untersuchungen eines heterogenisierten Katalysator-Photosensibilisator-Systems, bei dem ein Polyoxometalat-Katalysator zur Wasseroxidation und ein molekularer Modell-Photosensibilisator gemeinsam in einer nanoporösen Blockcopolymer-Membran immobilisiert wurden. Mittels elektrochemischer Rastersondenmikroskopie (SECM) wurde die lichtinduzierte Sauerstoffentwicklung mit Natriumperoxodisulfat (Na 2 S 2 O 8 ) als Opferelektronenakzeptor an den modifizierten Blockcopolymer-Membranen lokal bestimmt. Ex situ elementspezifische Analysen erzielten räumlich Informationen über die lokale Konzentration und Verteilung der molekularen Komponenten. Untersuchungen der modifizierten Membranen mittels abgeschwächter Infrarot-Totalreflexion (IR-ATR) zeigten keinen Abbau des Wasseroxidationskatalysators unter den beschriebenen lichtinduzierten Bedingungen.