Engineering the atomic interface of porous ceria nanorod with single palladium atoms for hydrodehalogenation reaction

Tuning the electronic properties of single atom catalysts(SACs)between the central metal and the neighboring surface atoms has emerged as an efficient strategy to boost catalytic efficiency and metal utilization.Here we describe a simple and efficient approach to create atomically dispersed palladium atoms supported over defect-containing porous ceria nanorod containing palladium up to 0.26 wt.%.The existence of singly dispersed palladium atoms is confirmed by spherical aberration correction electron microscopy and extended X-ray absorption fine structure measurements.This catalyst shows excellent efficiency in hydrodehalogenation reactions at low H2 pressure under mild conditions,along with satisfactory recyclability and scalability.Density functional theory(DFT)calculations reveal that the high activity stems from the spatial isolation of palladium atoms and the modified electronic structure of palladium confined in defect-containing ceria nanorod.This work may lay the foundation for the facile creation of single atom catalysts within the synthetic community and shed light on the possibility for scale-up production.

An effective method for the hydrodehalogenation of organic halides

THE reduction of organic halides to the corresponding hydrocarbons plays an important role inorganic synthesis and environmental decontamination.It is one of the earliest reactions de-scribed in the organic chemical literature.A number of successful approaches have been report-ed hitherto,but the hydrodehalogenation of chloroarenes and organic fluorides is still a

Highly selective hydrogenation of halonitroaromatics to aromatic haloamines by ligand modified Ni-based catalysts

Ligand modification of Ni-based catalysts by coordination of dicyandiamide to Ni metal leads to enhanced selectivity for the selective hydrogenation of halonitroaromatics.The selectivity of above 99.9%to aromatic haloamines can be achieved at the conversion of 100%.The results of H_2-TPD and FT-IR experiments show that Ni^-H~＋ species possessing the properties of Lewis acid site on the surface of Raney Ni could be responsible for the hydrodehalogenation.When Raney Ni was treated by dicyandiamide,Ni^-H~＋ species interacted with N atom from the dicyandiamide.This interaction was stable even at reaction temperature,which reduced the possibility to form the intermediate state of Ar-Cl...H~＋Ni^-.And then C-Cl bond could not be polarized and activated.The hvdrodechlorination process was suppressed effectively.

Palladium nanoclusters entrapped in polyurea:A recyclable and efficient catalyst for reduction of nitro-benzenes and hydrodechlorination of halogeno-benzenes

Polyurea-entrapped palladium nanoclusters have been prepared by interfacial polymerization in W/O emulsion and showed high thermal stability and chemical stability with the content of 0.12 mmol g-1 Pd.This catalyst exhibited dual catalytic activity for reduction of nitro compounds and hydrodehalogenation of aromatic chlorides in atmospheric hydrogen with 100% yield for reduction of nitro compounds and 】99% yield for hydrodehalogenation of aromatic chlorides.This immobilizing method was particularly effective and eliminated the need of special chelating groups.

FeCl_3·6H_2O-catalyzed selective reduction of allylic halides to alkenes with concomitant oxidation of benzylic alcohols to aldehydes

Iron-catalyzed direct reduction of allylic halides with benzylic alcohol was achieved,providing a new,simple,and efficient method for conducting highly regioselective hydrodehalogenation.This method not only features a readily available reductant,an inexpensive catalyst,simple manipulation,and good tolerance of functional groups including nitriles,nitro,esters,and methoxyl groups,it also has mild reaction conditions and shows complete regioselectivity in that only halides sited at the allylic position are reduced.Alternatively,this method can be applied in the selective transformation of benzylic alcohols to aromatic aldehydes without overoxidation to carboxylic acids.