Intermetallic PtBi Nanoplates Boost Oxygen Reduction Catalysis with Superior Tolerance over Chemical Fuels

The crossover issue of small-molecule organic fuels usually makes the Pt-based nanocatalysts exhibit low efficiency, and poor tolerance and durability under the practical fuel cell operating conditions. Here, a new approach to prepare a class of intermetallic hexagonal PtBi nanoplates with superior tolerance over chemical fuels for boosting oxygen reduction catalysis is reported. The time-dependent morphology studies reveal that the well-defined hexagonal PtBi nanoplates are transformed from a new reaction immediate (triangular/truncated triangular bismuth oxides nanoplates). Different from conventional Pt-based catalysts, the hexagonal PtBi nanoplates exhibit much improved tolerance over CH3OH, HCOOH, and CO. X-ray photoelectron spectroscopy results reveal that the charge displacement resulting from Pt-Bi bonding is the main factor in enhancing the tolerance. The PtBi nanoplates also exhibit much higher ORR activity than all the reported PtBi nanoparticles. Considering their exceptional antipoisoning ability and high activity, these hexagonal nanoplates show great potential in the development of commercial fuel cells.