화학공학소재연구정보센터
Journal of Materials Science, Vol.55, No.1, 125-139, 2020
"Romanesco broccoli"-like palladium nano-fractals for superior methanol electro-oxidation
Palladium nanoscale particles possessing distinct planes/facets for fuel cell applications are challenging to construct using simple methods. This work exhibits a facile-solution phase room-temperature synthesis of highly branched and exceptionally ordered 3D Pd nano-fractals (200-300 nm). Using high-resolution atomic imaging, we explain the mechanism of growth and proliferation of facets after twinning. Due to its unique and novel shape, there is an unprecedented 2.025 eV blue shift in d-region of XPS spectra of Pd nano-fractals indicating a phenomenal increase in surface electron density. This is highly favorable for utilizing this promising catalyst for enhanced surface activity. The Pd nano-fractal structures are tested as anodic material, and they show significantly enhanced electrocatalytic activity and superior long-term stability towards methanol oxidation reaction in alkaline media. Thus, low-index enclosed Pd nanostructures could be useful catalysis materials if uniquely shaped and morphologically controlled at nanoscales.