Green synthesis of Terminalia arjuna-conjugated palladium nanoparticles (TA-PdNPs) and its catalytic applications

Metal nanoparticles have drawn a great attention of scientific community due to a combination of their shape and size dependent unique properties like chemical, physical, theromodynamic, optical, electronic etc. and these have found increasing applications in pharmacology, bio-diagnostics, medicine, drug-delivery, catalysis, coatings, solar cells, purification of water, etc. [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Palladium nanoparticles are highly interesting than other transition metal nanoparticles for their usefulness in both homogeneous as well as heterogeneous catalysis due to their high surface-to-volume ratio and high surface energy. Use of palladium nanoparticles as a catalyst for various C–C coupling reactions such Suzuki and Heck coupling reactions has been highly exploited in organic synthesis [ 10 , 11 , 12 , 13 , 14 , 15 ]. Palladium nanoparticles have also been used as a catalyst in hydrogenation of alkenes, alkynes, allyl and benzyl alcohols and hydrogenolysis of allylic and benzylic ethers [ 16 , 17 , 18 ]. However, the examples of the utilization of phytochemical-conjugated PdNPs in C–C coupling reactions and degradation of dyes are rare [ 19 , 20 , 21 ].