Single step synthesis of bio-inspired NiO/C as Pd support catalyst for dual application: Alkaline direct ethanol fuel...

Carbon dioxide (CO₂) is considered a useful greenhouse gas that can be captured and be used in the electro-syntheses of useful chemicals or fuels. On the other hand, there's also a tremendous interest on ethanol beneficiation as it is largely produced from crops, and it is regarded as a potential candidate for low temperature fuel cell applications. Although ethanol possesses good advantages, its resistant to oxidation poses a threat. The main objective of the study is to synthesis bio-inspired metal oxide-support catalyst which will help enhance the activity, efficiency and selectivity of Pd catalyst in CO₂ reduction, Fuel cell performance and ethanol oxidation. Here, Pd nanoparticles were supported on NiO/C through a green facile one-step process using pomegranate peel extracts as reducing agent. A series of characterizations were carried out to provide proof for and to quantify the presence of Pd, Ni, O and C in the prepared sample. Microscopic methods confirmed the successful preparation of pure NiO/C and (%5 Pd) Pd-NiO/C, evident by the key elemental components, mixed nanostructures and co-existence of Pd and NiO/C. The resultant Pd-NiO/C nanocatalyst revealed higher activity towards the oxidation of ethanol and that the nanocatalyst is more tolerant to poising by intermediate oxidation species. Enhanced cell performance with current and power densities of 66 mA cm^-2 and 26 mW cm^-2 relative to the commercial Pd/C were obtained under passive conditions at 1 M ethanol in 1MKOH. In addition, the nanocatalyst showed good selectivity to HCOOH with enhanced current efficiencies of 45%.