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The performance of OER anodes based on supported nanocatalysts is highly dependent on the interactions taking place at the interface between the nanocatalyst and the employed conductive support. Herein, the versatility offered by the organometallic approach for the synthesis of metal-based nanostructures allowed preparing electrodes of tailored nanocatalyst–support interactions. A set of OER working electrodes based on Co(OH)2nanoparticles (NPs) and carbon microfibers (CFs) were prepared. The so-obtained systems differ in either the stabilizer present at the surface of the NPs (THF or 1-heptanol), the surface functionalization of the used CFs (bare CFs or oxidized-CFs) or the growth of the NPs in the presence (in situ) or the absence (ex situ) of the carbonaceous support. Correlation of a detailed structural and compositional analysis with the electroactivity of the tested nanomaterials allows extracting valuable insights about the influence of the metal–support interface on the OER performance of the studied anodes.

A new family of Ru–Hbpp dinuclear complexes containing the positively charged terpyridine derivative ligand 4-(-p-(pyridin-1-ylmethyl)phenyl)-2,2′:6′,2′-terpyridine of general formula {[Ru(L1+)]2(μ-bpp)(L-L)}m+(L-L = μ-Cl, μ-acetato, or (H2O)2; m= 4 or 5) have been synthesized and fully characterized, both in the solid state (X-ray diffraction) and in solution (1D and 2D NMR spectroscopy, UV–vis spectroscopy and electrochemical techniques). New hybrid materials have been prepared by the electrostatic interaction of these complexes with several oxidatively rugged solid supports such as SiO2, FTO–TiO2and FTO–Nafion®. These new hybrid materials were prepared and catalytically evaluated with regard to their capacity to chemically and electrochemically oxidize water to dioxygen.

This paper reports the comparison of the chemoselectivity of two different Pd catalytic systems, namely molecular and colloidal systems, in C–C coupling reactions. For this purpose, new hybrid pyrazole derived ligands containing alkylether, alkylthioether or alkylamino moieties have been synthesized and used to form Pd(ii) complexes and to stabilize Pd nanoparticles (Pd NPs). With the aim of studying the coordination mode of the ligands and further to understand their role in catalysis, both types of Pd species were characterized by appropriate techniques. In C–C coupling reactions promoted by different Pd colloidal systems, several reports evidenced that active species are molecular catalysts leached from Pd NPs. The most important feature of this work relies on the differences observed in the output of C–C coupling reactions, depending on the colloidal or molecular nature of the catalyst employed. Thus, molecular systems carry out typical Suzuki–Miyaura cross-coupling, together with the dehalogenation of the substrate in different proportions. In contrast, Pd NPs catalyze either Suzuki–Miyaura or C–C homocoupling reactions depending on the haloderivative used. Interestingly, Pd NPs catalyze the quantitative dehalogenation of 4-iodotoluene. Differences observed in the chemoselectivity of these two catalytic systems support that reactions carried out with Pd NPs stabilized with the hybrid pyrazole ligands employed here take place on the surface of the colloids.