The integration of molecular photosensitizers and catalysts into functional soft matter supports holds great promise for future energy conversion technologies.

An Ir(I) (NHC)-based hybrid material was prepared using a methodology which allowed the precise positioning and isolation of the Ir centers along the pore channels of a silica framework. The full characterization of the material by solid-state NMR spectroscopy showed that the supported Ir sites were stabilized by the silica surface, as low-coordinated single-site complexes. The material is extremely efficient for the hydrogenation of functional alkenes. The catalytic performance (TOF and TON) is one to two orders of magnitude higher than those of their molecular Ir analogues, and could be related to the prevention of the bimolecular deactivation of Ir complexes observed under homogeneous conditions.

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.

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This work demonstrates the use of imidazolium-based poly(ionic liquid)s (PILs) as efficient dispersants of multi-walled carbon nanotubes (MWCNTs). With these polymeric dispersants, highly stable fine dispersions of MWCNTs (inks) can be easily prepared in aqueous media and applied for rather simple but efficient surface modification of screen-printed electrodes (SPEs). Such a modification of SPEs remarkably increases the electroactive surface area and accelerates the electron transfer rate due to synergistic combination of specific features of MWCNTs such as strong adsorptive property and high specific surface with the advantages of PILs like ion conductivity and dispersability. We further show that the PIL/MWCNT-modified SPEs can be beneficially utilized for direct electrochemical analysis of double stranded DNA (dsDNA). Specifically, it is exemplified by the direct electrooxidation of guanine and adenine bases in salmon testes dsDNA chosen as a model system. The linear ranges for the determination of dsDNA correspond to 5-500 µg/mL for the oxidative peak of guanine and 0.5-50 µg/mL for the oxidative peak of adenine. This makes direct electrochemical dsDNA detection with the use of the easy-preparable PIL/MWCNT-modified SPEs strongly competing to currently applied spectral and fluorescent techniques. Furthermore, we show that the developed constructs are capable of sensing a single point mutation in the 12-bases single-stranded DNA fragments. Such detection is of high clinical significance in choosing an adequate anticancer treatment, where the electrochemical identification of the point mutation could offer time and cost benefits.

The immobilization of homogeneous catalysts within nanoporous membranes gives access to catalytically active and multi-functional composite materials, e.g. for use in flow reactors.

Being the major renewable source of bio-aromatics, lignin possesses considerable potential for the chemical industry as raw material. Kraft lignin is a couple product of paper industry with an annual production of 55,000,000 ton/y and is considered the largest share of available lignin. Here we report a facile approach of Kraft lignin depolymerization to defined oligomeric units with yields of up to 70 wt.%. The process implies utilization of an aqueous base in combination with a metal containing catalyst and an alcohol under non-oxidative atmosphere at 300 °C. An advantage of the developed approach is the facile separation of the oligomer product that precipitates from the reaction mixture. In addition, the process proceeds without char formation; both factors make it attractive for industrialization. The suppression of the repolymerization processes that lead to char formation is possible when the combination of metal containing catalyst in the presence of an alcohol is used. It was found that the oligomer units have structural features found in phenol-acetaldehyde resins. These features result from the base catalyzed condensation of lignin fragments with in situ formed aldehydes. Catalytic dehydrogenation of the alcohol provides the latter. This reaction pathway is confirmed by the presence condensation products of Guerbet type reactions.

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.