Chemical functionalization or docking of transition-metal ions in covalent organic frameworks (COFs) is of importance for calibrating properties and widening potential applications. In this work, we demonstrate the successful decoration of COF with vanadium as exemplified in the context of post-synthetically modifying two-dimensional COF that features eclipsed stacking structure, large pores, hydroxyl functionalities, high thermal and chemical stability using vanadyl acetylacetonate. The potent catalytic behavior of vanadiumdecorated COF was systematically investigated in the reactions of Prins condensation and sulfide oxidation, which revealed its excellent catalytic performances in terms of efficacious activity, preservation of framework crystallinity and reusability. Our work not only contributes the first ever report of vanadium-decorated COF-catalyzed Prins reaction and sulfide oxidation but paves a new way for docking COF with metals for a broad range of applications.

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In this work, we present a facile aqueous-phase synthesis of a hybrid catalyst consisting of PtAu alloy supported on BiO microspheres. Multistep reduction of HAuCl and KPtCl salts on BiO and subsequent annealing lead to the formation of this hybrid catalyst. To the best of our knowledge, this is the first report of using BiO as a catalyst support in fuel cell applications. The material was characterized by powder X-ray diffraction and various microscopic techniques. This composite showed remarkable activity as well as stability toward the electro-oxidation of ethanol in comparison to commercially available Pt/C. The order of the reactivity was found to be commercial Pt/C (50.4 mA/mmg) < Pt/BiO(10) (108 mA/mmg) < PtAu/BiO(10) (459 mA/mmg). The enhancement in the activity can be explained through cooperative effects, namely, ligand effects of gold and BiO support, which helps in removing carbon monoxide molecules to avoid the poisoning of the Pt active sites.

CeO2 nanoboxes designed by controlling various chemical parameters enhance both the efficiency and stability of Pt nanoparticles towards the electrochemical oxidation of formic acid.