Controllable Synthesis and Enhanced Electrocatalysis of Iron-based Catalysts Derived From Electrospun Nanofi bers

摘要

Proton exchange membrane fuel cell (PEMFC) is one of the most promising energy conversion devices to solve the energy shortage without polluting the environment. [ 1 ] There are already many successful PEMFC models, such as the power sources in electric vehicles [ 2,3 ] and in the microano-devices of our previous works. [ 4 ] But, their commercialization and widespread implementation are limited by high cost, weak durability and poor poison tolerance of Pt-based catalysts. [ 5 ] A mass of Pt-based catalysts are required for reducing the overpotential of oxygen reduction reaction (ORR) in the acidic environment of the cathode of PEMFC. [ 6 ] Although many studies have utilized shape-controlling, [ 7 ] alloying with other elements [ 8–11 ] and modifying with nanoparticles [ 12 ] to improve Pt-based catalysts, the high costs of the catalysts cannot be really reduced. Several delicate processes have been invented to produce inexpensive catalysts of transition metal coordinated with nitrogen on carbon support (TMN-C), which are promising substitutes for Pt-based catalysts. [ 13–22 ] Their catalysis active sites are TM-N x, which were discovered by Jasinski, [ 23 ] and can be achieved by heating a mixture of transition metal salt, nitrogen source and carbon support. [ 13–15,24,25 ] In addition to TM-N-C, metal-free catalysts, such as nitrogen-doped graphene, [ 20,26 ] carbon nanotubes [ 27 ] and carbon nanocages, [ 28 ] have also shown good ORR performance.