Highly coordinated Pd overlayers on nanoporous gold for efficient formic acid electro-oxidation

Design and fabrication of highly efficient and stable electrocatalysts remain key challenges in green energy technologies such as low-temperature direct liquid fuel cells.Based on in-depth theoretical calculations,here we demonstrate that surface Pd atoms with high coordination numbers(HCNs)can effectively modulate their adsorption energies for CO and OH,and thus achieve very high performance for formic acid electro-oxidation reaction(FAOR).Based on epitaxial coating Pd atomic layers onto nanoporous gold(NPG)thin membranes and a slight further decoration of Au clusters on top,the resulted core-shell structured NPG-Pd-Au electrocatalyst can demonstrate Pd intrinsic and mass activities of 8.62 mA·cm^(-2)and 27.25 A·mg^(-1)respectively at the peak potential around 0.33 V versus saturated calomel electrode toward FAOR,which are far better than those of commercial Pd/C catalysts(1.09 mA·cm^(-2)and 0.32 A·mg^(-1))tested under the same conditions.Moreover,the membrane electrode assemblies based on these low precious metal loading electrodes can achieve an anode Pd power efficiency over 10 W·mg^(-1)in a direct formic acid fuel cell,which is two orders of magnitude higher than that of the commercial Pd/C.These results provide new inspirations for the development of revolutionary electrodes for energy technologies in a rational manner.

High Li^(+)coordinated solvation sheaths enable high-quality Li metal anode

An advance Li-sphere possessing a definitely regular morphology in Li deposition enables a well-defined more robust structure and superior solid-electrolyte interphase(SEI)to achieve high-efficiency long-term cycles in Li metal anode.Here,a new sight of high Li^(+)cluster-like solvation sheaths coordinated in a localized high-concentration NO_(3)^(-)(LH-LiNO_(3))electrolyte fully clarifies for depositing advanced Li spheres.Moreover,we elucidate a critical amorphouscrystalline phase transition in the nanostructure evolution of Li-sphere deposits during the nucleation and growth.Li-sphere anode exhibits ultrastable structural engineering for suppressing Li dendrite growths and rendering ultralong life of 4000 cycles in symmetrical cells at 2 mAcm^(-2).The as-constructed Li spheres/3DCMjLiFePO_(4)(LFP)full cell delivers a high capacity retention of 90.5%at 1 C after 1000 cycles,and a robust dendrite-free structure also stably exists in Li-sphere anode.Combined with high-loading LFP cathodes(6.6 and 10.9 mg cm^(-2)),superb capacity retentions are up to 96.5%and 92.5%after 800 cycles at 1 C,respectively.Cluster-like solvation sheaths with high Li^(+)coordination exert significant influence on depositing a highquality Li-sphere anode.

A new power coordination method for islanded micro-grid basing on multi-agent system

Multi-agent system (MAS) can provide flexible and intelligent control for micro-grid (MG). In this paper, a new power coordination method of MAS is presented for MG. New way for dispatching controllable generations (CGs) and direct cooperation between storages and CGs are designed. Real-time emulations of the coordination, including the usage of both CGs and storages, have been carried out in islanded situation basing on this method, and much higher performance than conventional method is found.