Bimetallic core-shell nano-structured catalysis, has sparked great attention due to their multiple possibility of morphology, atomic arrangement and composition. In the present study, three bimetallic core-shell based nanocatalysts viz. Pd(0)@enSiO2-TiO2-Ni,...

With an aim to combine the catalytic properties of Pd nanoparticles (NPs) with the excellent characteristics of porous layered double hydroxides (LDH), in the present study, four different catalysts (Pd/Fe 3 O 4 -CoTiMgAlLDH, Pd/Fe 3 O 4 -CoTiMgLDH, Pd/Fe 3 O 4 -CoTiAlLDH and Pd/Fe 3 O 4 -CoTiLDH) were synthesized by supporting Pd NPs onto four different Fe 3 O 4 -LDH supports, which were synthesized by varying the metals in LDH. The catalytic activity of these catalysts was studied for Suzuki coupling and reductive degradation of dyes. Pd/Fe 3 O 4 -CoTiMgLDH outperformed the other catalysts in both reactions. The synthesized catalysts were examined via different characterization techniques like X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), high resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), energy dispersive X-ray mapping (SEM-EDX mapping), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and vibrating sample magnetometry (VSM).On the basis of results obtained from XPS and the experimental data, Fe 3 O 4 -CoTiMgLDH was found to be the support of choice as it not only stabilized the Pd 0 NPs but also increased the electron density on the anchored Pd 0 species, which enhanced the catalytic activity of Pd/Fe 3 O 4 -CoTiMgLDH for studied organic transformations.

The development of novel bio-based heterogeneous catalytic systems with easy separation and recyclability is significant in chemical synthesis. In this work, palladium nanoparticles have been successfully anchored on to the surface of MnO2 modified cotton fabric via a facile method for the synthesis of Pd(0)@MnO2-CF catalyst. Several characterization methods including FEG-SEM, EDX, XRD, FTIR, TGA, ICP-AES and XPS were used to confirm the immobilization of Pd NPs onto the cotton fabric. The catalytic activity of synthesized catalyst, Pd(0)@MnO2-CF, was evaluated for oxidation of alcohols, oxidative deprotection of oximes and degradation of methyl orange for which it demonstrated good activity. Besides, easy separation of the catalyst from the reaction mixture is one of its major advantages as it eliminates the need to employ other tedious work-up procedures. Further, the reusability of Pd(0)@MnO2-CF was studied by performing oxidation of 4-bromobenzyl alcohol and oxidative deprotection of 4-bromobenzaldehyde oxime consecutively for five times and a minor loss in catalytic activity was observed.

Enhancing the stability of metal nanoparticles is of great interest in the field of heterogeneous catalysis. An attractive prospect to this is incorporation of metal nanoparticles into metal organic frameworks...