Search

The development of electrocatalyst possessing superior oxygen reduction reaction (ORR) activity is highly desirable due to the low sluggish kinetics at the cathode of fuel cell. Here, CoFe 2 O 4 nanoparticles embedded in N-doped carbon nanotubes electrocatalyst (denoted as CoFe 2 O 4 -NC) is synthesized via polymerization of pyrrole, absorbing metal ion and annealing under Ar/NH 3 atmosphere. By in situ integrating the catalytically active CoFe 2 O 4 nanoparticles with the N-doped carbon nanotubes and enhancing electrical conductivity, the as-obtained electrocatalyst exhibits excellent ORR activity and long-term stability with a half-wave potential of 0.86 V and 10 h continuous cycling, outperforming the reported similar catalysts. This work opens a new path for the expansion of low cost and efficient ORR electrocatalysts to substitute Pt-based metals for energy storage and conversion devices. [Display omitted] • In situ synthesis of CoFe 2 O 4 nanoparticles embedded in N-doped carbon nanotubes. • CoFe 2 O 4 -NC exhibits excellent ORR activity with a half-wave potential of 0.86 V and long-term stability. • The immobilization of particles on carbon tube prevents the CoFe 2 O 4 nanoparticles from dissolving or aggregating. [ABSTRACT FROM AUTHOR]

At present, the preparation of highly active, long-term durable, and low cost electrocatalysts toward oxygen evolution reaction is still a challenge for energy conversion and storage. This work reports CoS 1.097 embedded in flower-like biomass derived from red blood cells (RBCs) nanocatalyst, was synthesized via a one-step, hydrothermal method. Compared to pure CoS 1.097 microspheres, the generated flower-like CoS 1.097 -biomass (CoS 1.097 -B) nanosheets exhibits enhanced OER electrocatalytic activity with a onset potential of 1.43 V (vs. RHE), an overpotential of 260 mV at the current density of 10 mA cm−2, and a low Tafel slope of 83 mV dec−1. Moreover, the CoS 1.097 -B displays good OER stability with little decrease after 400 cycles. Our work provides a reference for designing catalysts with high activity and good stability using biomass under mild conditions. Image 1 • Novel synthesis of CoS 1.097 embedded in flower-like biomass nanocatalysts. • More exposed CoS 1.097 particles impart large active area. • The CoS 1.097 -B exhibits excellent activity and stability towards OER. • The CoS 1.097 -B requires an overpotential of 260 mV to reach a current density of 10 mA cm−2. • The Tafel slope of CoS 1.097 -B is only 83 mV dec−1. [ABSTRACT FROM AUTHOR]