Solid-state grinding of palladium and copper salts allowed the growth of palladium/copper oxide interface at the zeolite-Y surface. The hybrid nanostructured material was used as reusable heterogeneous catalyst for selective oxidation of various benzyl alcohols. The large surface area provided by the zeolite-Y matrix highly influenced the catalytic activity, as well as the recyclability of the synthesized catalyst. Impregnation of PdO-CuO nanoparticles on zeolite crystallite leads to the generation of mesoporous channel that probably prevented the leaching of the metal-oxide nanoparticles and endorsed high mass transfer. Formation of mesoporous channel at the external surface of zeolite-Y was evident from transmission electron microscopy and surface area analysis. PdO-CuO nanoparticles were found to be within the range of 2-5 nm. The surface area of PdO-CuO-Y catalyst was found to be much lower than parent zeolite-Y. The decrease in surface area as well as the presence of hysteresis loop in the N-adsoprtion isotherm further suggested successful encapsulation of PdO-CuO nanoparticles via the mesoporous channel formation. The high positive shifting in binding energy in both Pd and Cu was attributed to the influence of zeolite-Y framework on lattice contraction of metal oxides via confinement effect. PdO-CuO-Y catalyst was found to oxidize benzyl alcohol with 99% selectivity. On subjecting to microwave irradiation the same oxidation reaction was found to occur at ambient condition giving same conversion and selectivity.

Pd–Au nanoalloy supported on zeolite-Y (Pd–Au–Y) matrix was found to be an effective catalyst for C–Cl bond activation and oxidative coupling of 2-naphthol, leading to the formation of various biaryl products and 1,1′-bi-2-naphthol, BINOL. The same catalyst was also highly efficient for selective oxidation of benzylic alcohols to benzaldehydes. Cinnamaldehydes were obtained directly from benzaldehydes by aldol condensation with acetaldehyde generated in situ by partial oxidation of ethanol in the presence of Pd–Au–Y catalyst at 120 °C under basic condition. The biaryl products were also obtained directly from benzylic alcohols in a one-pot system by reacting with phenylboronic acid. The formation of biaryls from benzylic alcohols was believed to occur via one-pot benzylic C–H and C–Cl bond activation. A high % yield of biaryls, BINOL, aldehydes, and cinnamaldehydes was obtained by performing different reactions using the single Pd–Au–Y catalyst. The strong interaction of chloro-benzylic alcohol was predominantly located at active gold species. X-ray photoelectron and diffuse reflectance spectroscopic studies revealed the strong interaction between Pd and Au particles. Electrochemical studies provided proper evidence for the individual role of the nanoparticles (NPs) in one-pot synthesis of biaryls from benzylic alcohols.

Pd–NiO hybridized with zeolite and multiwalled carbon nanotube appeared as highly effective electrocatalyst in methanol oxidation reaction.

Selective reduction of various nitroarenes to amines was achieved up to 93% under autoclave condition in isopropanol using catalytic amount of palladium oxide/copper oxide (PdO/CuO) nanoparticles (NPs) supported on mesoporous zeolite-Y, PdO/CuO-Y. The catalyst was also found to be highly effective for one-pot cascade synthesis of the 3,3′-diaminobiphenyl from 3-nitrophenylboronic acid (NPBA). The hybridization of PdO/CuO-Y with multiwalled carbon nanotubes (MWCNTs) resulted in a highly effective and durable electrocatalyst for the methanol oxidation reaction (MOR). The mass activity of the electrocatalyst was found to be 690 A/g and was stable for 4000 s. The catalytic activity of the PdO/CuO-Y catalyst was found to be superior in terms of productivity and recyclability in comparison to that of the bared PdO/CuO NPs separated by the ultracentrifugation (UC) method. On the other hand, the one modified with the carbon matrix retained the same activity and reduced the reaction time in nitroarene reduction reaction (NAR) under identical conditions. Electrochemical studies and density functional theory (DFT) calculations were performed to understand the mechanism of the NAR process. Both the experimental and theoretical evidence explicitly demonstrated the individual role of both palladium (Pd) and copper (Cu). Pd was found to be the active site for nitroarene interaction, while CuO NPs played an important role in isopropanol oxidation.

Chiral Ni­(II)-Schiff base complexes synthesized inside the cavity of zeolite-Y were used as heterogeneous chiral catalyst for asymmetric Henry reaction. Synthesized catalysts were characterized using various spectrochemical and physicochemical techniques. Solid state NMR analysis has been used to confirm the internal location of the metal complexes. To the best of our knowledge MAS NMR has not been used to characterize chiral diamagnetic Ni2+-Schiff base complex inside zeolite-Y. The catalytic activities of the materials were dependent on temperature, solvent, and amount of catalyst. High catalytic transformation of aldehydes with nitromethane to nitro-aldol product (92% yield and 83% ee, S-isomer) was achieved at −10 °C. Initial activation of the reaction with microwave irradiation for 15 min leads to a substantial decrease in the reaction time in comparison to normal stirring. Heterogeneous catalysts were found to be advantageous over the homogeneous counterparts in terms of recyclability of the catalyst. Most importantly, product selectivity, percentage yield, and enantioselectivity were found to be high with the heterogeneous catalyst. The catalytic activities of the metal complexes were influenced by the structural modification of the Schiff base ligands. Calculation of the energy barrier using density functional theory (DFT) suggests that the activation barrier is less in the case of the encapsulated complexes.