Efficient synthesis of palladium nanoparticles using guar gum as stabilizer and their applications as catalyst in reduction reactions and degradation of azo dyes

摘要

Palladium is very expensive metal and has numerous applications especially as a versatile hydrogenation and dehydrogenation catalyst for chemical -reactions. The main hurdle in its wide use is the high materials cost. In the present study a cost effective palladium nano catalyst was prepared using the green method of synthesis with guar gum as capping and reducing agent. The formations of palladium nanoparticles were confirmed by -UV-spectrophotometer while for morphology and nature, SEM and XRD were performed that confirmed the crystalline nature of PdNPs and proved the roughly spherical shape of nanoparticles. FT-IR analysis showed different functional groups of reducing agent and proved that guar gum have the ability to stabilized as well as to reduce the Pd (II) to Pd (0). Specific signal for the palladium is present in EDX spectra that further confirmed the formation of PdNPs. The catalytic efficiency was studied using the hydrogenation of 4-nitrophenol. Rate constant of prepared nano-catalyst was 0.1436/min, its efficiency, TON, TOF, in above mention reaction is 90.83, 27.78, and 185.2/hrs, respectively. Data obtained proved synthesized PdNPs to be efficient heterogeneous catalyst for the reduction of 4-NP and for the degradation of azo dyes.