Abstract
A rational design and selection of electrocatalytic cathode host materials are significant to achieve sustainable, efficient and stable catalysis towards H2O2 electroreduction. Herein, we described a facile synergetic strategy to generate a novel free-standing electrode (Pd-Co3O4/3D RGO@polyimide (PI) foam, PCRP) with well-developed porous and hollow structure, which derived from cobalt-based MOFs (ZIF-67) as an advanced Pd host, rooting on the 3D conductive graphene/PI foam to realize the significant promotion towards H2O2 electroreduction. Such 3D hollow structure design not only offers a high specific area to develop a number of exposed catalytic activity sites but also restricts the aggregation of nanoparticle catalysts within catalysis. Utilizing the electrode structural advantages and reducing the particle diameter of noble metal catalysts to improve the catalytic performance was possible. When evaluated as a co-catalyst for H2O2 electroreduction, the as-developed electrode displayed an optimized reduction current density of 962 mA·cm?2 at ?0.8 V in alkaline due to the synergetic influence of Pd nanoparticles and Co3O4 hollow cages. Notably, the loading of noble metal on the PCRP electrode was only close to 2.0 wt% in Pd-Co3O4 hybrids. What's more, the obtained PCRP electrode also exhibited robust stability, low apparent activation energy (9.071 kJ·mol?1), good reproducibility and repeatability (903 mA·cm?2after 1000 cycles with a 0.0058% current density decay per cycle at ?0.8 V) superior to that of single Co3O4 nanoparticles or Co3O4/3D RGO hybrids with simple configuration, implying its great promise for novel energy transformation systems.
NSTL
Elsevier