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At present, it is still a great challenge to control the morphology and size of nanoparticles for obtaining more efficient and stable catalysts for direct fuel cell reactions. Herein, we have synthesized a series of Pd3Sn bimetallic catalysts with different morphologies that transitioned from nanonetwork to nanostrips and then to nanodots by altering the varieties of reducing agents and the amount of surfactant. And the formation mechanisms of nanocatalysts were also investigated. It is worth noting that Pd3Sn-dots, due to the unique structure, uniform dispersion and ultra-small size, exhibit excellent electrocatalytic activity for ethanol oxidation reaction and ethylene glycol oxidation reaction, which distinctly higher than the other Pd3Sn catalysts and commercial Pd/C catalysts. Moreover, the as-prepared Pd3Sn catalysts also performed greater long-term durability due to the electronic and synergistic effects. This work provides guidance on the morphology-dependent nanocrystals, which will show a great potential as anodic catalysts in direct fuel cell applications.

High-efficiency adsorption of solar energy is a lofty goal and the pursuit of efficient photocatalyst is also one of the tough challenges. It's a growing interesting in the technology that is on the basis of surface plasma resonance (SPR) plasma resonance of the alloy nanoparticles (NPs). We herein successfully design a facile class of trimetallic Pt-Ag-Ni alloy NPs that combined the advantages of electronic effect, size and synergistic effect. Impressively, the Pt2Ag1Ni1 NPs possess excellent electrocatalytic under visible light ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR) with the mass activity founded to be: 7.99 and 4.88 A/mg, respectively. More significantly, SPR effect induces the optimal Pt-Ag-Ni NPs mass activity enhancement at 1.83 and 1.78 times higher under visible light than under environmental conditions. The design and SPR investigation of the trimetallic Pt-Ag-Ni alloy NPs in the research may provide a new approach for further development of high-performance nanocatalysts.

Trimetallic PdAgCu hollow nanospheres (HNSs) electrocatalysts have been synthesized by a mediated and galvanic replacement method. Owing to the introduction of transition metals like Ag and Cu, the unique hollow sphere-like structure, electronic effects among the ternary metals and so on, the electrocatalytic activity and durability have been tremendously enhanced. In detail, PdAgCu HNSs show superior electrocatalytic performances for ethylene glycol oxidation reaction (EGOR) with the mass activity of 3230.4 mA/mgPd and retained mass activity of 211 mA/mgPd after the durability measurement towards ethylene glycol oxidation, which are 3.39 and 3.05 times higher than those of commercial Pd/C, respectively, indicating that the PdAgCu HNSs possess the most powerful functionality in both electrocatalytic activity and stability. Remarkably, based on the present method, large-scale commercialization of PdAgCu HNSs electrocatalysts with low-priced, easy-to-use, and eco-friendly properties will in part assist in sustainable development.

The surface plasmon resonance (SPR) effect on noble metals to convert solar energy into chemical has attracted a lot of interest. However, the lack of highly efficient photocatalysts is still the forbidden obstacle as well as their large-scale development. Therefore, we focus on plasmon resonance enhanced electrocatalytic oxidation of liquid fuel employing photocatalysts to develop unique hollow platinum-silver (Pt-Ag) nanocrystals. The hollow Pt-Ag is formed of nanodendrites (Pt1-Ag1) which display a great enhancement in catalytic activity towards ethylene glycol oxidation with the mass and specific activity found to be: 7045.2 mA/mg and 14.1 mA/cm2, respectively. This is due to: the SPR effect, efficient electronic distribution and synergistic properties, together with the unique hollow dendritic nanostructures. Impressively, the SPR effect also induces the optimum Pt-Ag nanocatalsyst under visible light irradiation conditions to display 1.7-fold enhancements in catalytic activity compared to that under dark conditions. In addition, 6.2 and 7.0-fold enhancements were obtained when the optimized Pt-Ag was employed as photoelectrocatalyst compared to the commercial Pt/C. Therefore, we present a unique catalyst which produces a high catalytic activity and long-term stability compared to those previously reported. More importantly, we also introduce a promising approach towards the designing of a plasmonic metal nanocatalyst with ideal nanostructures for liquid fuel oxidations.

Facilely tuning the nanocrystals with fascinating morphology represents a versatile approach to fabricate the ideal nanocatalysts with both enhanced catalytic activity and stability toward liquid fuel electrooxidation due to their abundant surface active areas, facilitated charger transfer, as well as the synergistic effects. However, up till now, the rational fabrication of trimetallic nanocrystals with both fascinating morphology and tunable compositions remain a challenge. To this end, we herein demonstrate a facile wet-chemical method to successfully synthesize the unique pinecone-like Pd–Au–Ag nanocatalysts with the assistance of cetyltrimethylammonium bromide (CTAB). A series of electrochemical measurements have revealed that the resulted pinecone-like Pd–Au–Ag nanocatalysts exhibited unprecedentedly high catalytic activity with the mass and specific activities of 7150.8 mA/mg and 18.2 mA/cm2 toward ethylene glycol oxidation, 7.25 and 2.14 times higher than that of commercial Pd/C (986.4 mA/mg and 8.5 mA/cm2), respectively. Our efforts in this work may open up a new way for maximizing the electrocatalytic performances of catalysts by facilely designing and adjusting their morphologies and we also trust that the electrocatalysts fabricated in this work can be well applied as potential anodic catalysts and beyond.

In this study, three-dimensional (3D) porous PdCu bimetallic alloys were synthetized through a facile one-pot method by employing hydrazine hydrate, polyvinylpyrrolidone and sodium bromide as the reducing agent, surfactant and structure-directing agent, respectively. The network nanostructure offers large open pores and special morphology which plays an important role in strengthening ethanol electrocatalytic activity and durability. The as-prepared 3D network PdCu nanocatalyst displays greatly enhanced electrocatalytic activities towards ethanol oxidation in alkaline medium. Notably, the catalyst with Pd:Cu atomic ratio of 1:1 exhibits the highest electrocatalytic activity, its mass activity of ethanol oxidation reaches 3362.50 mA/mg, which is 7.20 times than that of commercial Pd/C catalyst. This study suggests that introduction of copper could possibly improve the feasibility of the direct ethanol fuel cells for real world applications by improving electrocatalytic activity and lowering production cost.