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Self‐cross‐linkable ferrocenyl‐containing polymethylhydrosiloxanes were synthesized. Karstedt's catalyst and cis‐[PtCl2(BnCN)2] were examined as cross‐linking catalysts at room temperature for the reaction between Si–H groups of the ferrocenyl‐containing polymethylhydrosiloxanes. Cis‐[PtCl2(BnCN)2] is an effective catalyst that allows cross‐linked ferrocenyl‐containing silicones (silicone rubbers) to be obtained with no visible mechanical defects (bubbles or cracks) compared with Karstedt's catalyst. The ferrocene content of the ferrocenyl‐containing silicone rubbers was found to be approximately 50 wt.% by energy‐dispersive X‐ray analysis. Compared with cross‐linked non‐modified polymethylhydrosiloxanes, the ferrocenyl‐containing silicone rubbers exhibited improved tensile properties (the tensile strength increased from 0.47 to 0.75 MPa) and a 1.5–2.5 times lower cross‐linking degree. The surface resistivity of the ferrocenyl‐containing silicone rubbers (50 wt.% ferrocenyl units) was approximately 7 × 109 Ω/□, which was 10,000 times lower than that of pure polymethylhydrosiloxane. The obtained flexible electroactive ferrocenyl‐containing silicone rubbers can potentially be applied as coatings for electronic and electrostatic‐sensitive devices, interfaces, and sensors.

Cobalt(II)-pyridinedicarboxamide-co-polydimethylsiloxane (Co-Py-PDMSs) and cobalt(II)-bipyridinedicarboxamide-co-polydimethylsiloxane (Co-Bipy-PDMSs) polymer−metal complexes were prepared by complexation between Py-PDMSs or Bipy-PDMSs ligands and cobalt(II); the metal content in these complexes varied from 0.09 to 2.41 wt %. The Co II binding patterns (the Co−N Py and Co−O coordination in Co-Py-PDMSs and Co−N Bipy in Co-Bipy-PDMSs) were established by UV−vis and IR methods and by comparison with model Co II complexes exhibiting relevant O,N,O-and N,N-coordination environments, respectively. The mechanical properties of the polymer−metal complexes were controlled by the coordination of Py-PDMSs or Bipy-PDMSs to Co II at various metal-toligand molar ratios (1:(1−6)) and by the variation of the polydimethylsiloxane unit length (M n : 850−900, 5000, or 25 000 g•mol −1 ). Utilization of the chelated Py-PDMSs and Bipy-PDMSs polymer ligands, which are capable of tri-or bidentate binding of Co II , led to (2−4)-fold increases in tensile strength (up to 1.75 MPa) and much higher elongation at break ((2−3)-fold increase up to 2100%) compared with the previously reported Co II -based polymer− ligand systems featuring monodentate ligation entities. Changing the main-chain ligand from Py-PDMSs to Bipy-PDMSs led to an increase in tensile strength of (2−4)-fold in comparison with Py-PDMS and a lower hysteresis (4%). The room temperature selfhealing efficiency was up to 96% for Co-Py-PDMSs and 40% for Co-Bipy-PDMSs, as measured for a polydimethylsiloxane unit with M n = 25 000 g•mol −1 .

Two series of hybrid inorganic-organic derivatives, obtained via the modification of protonated Ruddlesden–Popper phases H2Ln2Ti3O10 (Ln = La, Nd) with intercalated n-alkylamines and grafted n-alkoxy groups, have been systematically investigated in relation to photocatalytic hydrogen production from a model of 1 mol % aqueous solution of methanol for the first time. Photocatalytic measurements were performed both for bare samples and for their composites with Pt nanoparticles as a cocatalyst using an advanced scheme, including dark stages, monitoring of the volume concentration of the sample in the reaction suspension during the experiment, shifts of its pH and possible exfoliation of layered compounds into nanolayers. It was found that the incorporation of organic components into the interlayer space of the titanates increases their photocatalytic activity up to 117 times compared with that of the initial compounds. Additional platinization of the hybrid samples’ surface allowed for achieving apparent quantum efficiency of hydrogen evolution of more than 40%. It was established that the photocatalytic activity of the hybrid samples correlates with the hydration degree of their interlayer space, which is considered a separate reaction zone in photocatalysis, and that hydrogen indeed generates from the aqueous methanol solution rather than from organic components of the derivatives.

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