1-Naphthol induced PtsAg nanocorals as bifunctional cathode and anode catalysts of direct formic acid fuel cells

Developing highly efficient bifunctional cathode and anode electrocatalysts is very important for the large-scale application of direct formic acid fuel cells. However, the high-cost and poor CO-tolera nee ability of the most commonly used Pt greatly block this process. To in crease the utilizatio n efficie ncy and exte nd bifunctional properties of precious Pt, herei n, coral-like Pt3Ag nano crystals are developed as an excelle nt bifunctional electrocatalyst through a facile one-pot solvothermal method. The formation mechanism of Ptgg nanocorals has been elaborated well via a series of control experiments. It is proved that 1-naphthol serving as a guiding surfactant plays a key role in the formation of high-quality nano corals. Thanks to the unique coral-like structure and alloy effects, the developed Ptgg nano corals present sign ificantly enhanced electrocatalytic properties (including activity, stability and CO-toleranee ability) towards both the cathodic oxygen reduction and anodic formic acid oxidati on, as compared with those of commercial Pt black and Pt-based nan oparticles. The prese nt synthetic method can also be extended to fabricate other bimetallic electrocatalysts with unique morphology and structure.

Trimetallic Au@PdPb nanowires for oxygen reduction reaction

The development of highly efficient and stable Pd-based catalysts is crucial to improve their sluggish oxygen reduction reaction(ORR)kinetics in acid media.To improve ORR activity and utilization efficiency of Pd,an ideal catalyst should have ORR-favorable chemical environment,optimized geometric structure,and long periods of operation.In this work,we first synthesize a novel trimetallic Au@PdPb core–shell catalyst consisting of PdPb alloy nano-layers grown on the surface of ultrathin Au nanowires(NWs)by a two-step water-bath method.The Au@PdPb NWs have the merits of anisotropic one-dimensional nanostructure,high utilization efficiency of Pd atoms and doping of Pb atoms.Because of the structural and multiple compositional advantages,Au@PdPb NWs exhibit remarkably enhanced ORR activity with a high haIf-wave potential(0.827 V),much better than those of commercial Pd black(0.788 V)and bimetallic Au@Pd NWs(0.803 V).Moreover,Au@PdPb NWs display better electrocatalytic stability for the ORR than those of Pd black and Au@Pd NWs.This study demonstrates the validity of our approach for deriving highly ORR-active Pd-based catalysts by modifying their structure and composition.