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A novel 4,4-difuoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) copolymer with diethynylbenzene has been synthesised, and its ability to act as a photosensitiser for the photocatalytic generation of hydrogen was investigated by time-resolved spectroscopic techniques spanning the ps-to ns-timescales. Both transient absorption and time-resolved infrared spectroscopy were used to probe the excited state dynamics of this photosensitising unit in a variety of solvents. These studies indicated how environmental factors can influence the photophysics of the BODIPY polymer. A homogeneous photocatalytic hydrogen evolution system has been developed using the BODIPY copolymer and cobaloxime which provides hydrogen evolution rates of 319 µmol h −1 g −1 after 24 h of visible irradiation.

Structural disorder is observed due to the fact that protonation, as well as oxidation, of the N atoms of 2,2′-bi­pyridine occurs either at either of the N atoms. The disorder extends to the remainder of the cation, with a refined occupancy rate of 0.717 (4) for the major moiety.

Amorphous hydrogenated carbon (a-C:H) films are applied 500 nm thick on Si(100) via plasma-enhanced chemical vapor deposition (PECVD) using ethyne. Present plasma conditions enrich the sp 2 -content especially toward the outermost a-C:H layers, which in turn are used to attach a photoactive Ru-polypyridyl complex to the surface. An azo-bridged dinuclear Ru-polypyridyl complex is optimized in synthesis and the final mononuclear fragment attached on a-C:H photochemically under UV-irradiation with concomitant N 2 release. The Ru-polypyridyl complex is characterized by MS, NMR, IR, UV/vis, fluorescence spectroscopy, and time-dependent density functional theory (DFT) calculations. Crystallographic data for the intermediate 4-nitro-2-(pyridin-2-yl)pyridine 1-oxide as essential precursor are established. Morphological characteristics of the a-C:H @ Si and final Ru(complex) @ a-C:H @ Si combinations are determined by atomic force microscopy (AFM) revealing individual grain-like structures. The presence of Ru on the a-C:H @ Si surface is initially verified qualitatively by laser-induced breakdown spectroscopy (LIBS) and by inductively coupled plasma-sector field mass spectrometry (ICP-SF-MS) after chemical digestion. With laser ablation-ICP-MS mapping, full Ru coverage is proven, also revealing inhomogeneities in terms of "Ru hot spots". The current investigation proves the successful attachment of a Ru-complex on a-C:H and indicates a starting point for the development of further material combinations for feasible sunlight to energy conversions. Surface FunctionalizationThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.