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Alloying the active metal with a second metal is an effective way to tailor the adsorption of reaction intermediates through an ensemble effect. Herein, based on theoretical calculations validating that the ensemble sites composed of Ag and Pd atoms could reduce the energy gap for *COOH and *CO intermediates generated during electrocatalytic CO2 reduction reaction (eCO2RR) by either weakening the CO adsorption or enhancing the COOH adsorption, a strategy to produce AgPd alloy nanoparticles with fine sizes for synergizing the ensemble effect and size leverage toward high CO faradaic efficiency in eCO2RR is reported. In particular, the AgPd alloy nanoparticles at an optimized Ag/Pd atomic ratio of 35/65 affords a maximum CO faradaic efficiency of 98.9% and a CO partial current density of 5.1 mA cm−2 at the potential of −0.8 V (vs RHE) with satisfactory durability of up to 25 h, outperforming those of most Pd‐based electrocatalysts recently reported and demonstrating great potential for further application in producing CO via eCO2RR at ambient conditions. [ABSTRACT FROM AUTHOR]

Corporate probability of default (PD) prediction is vitally important for risk management and asset pricing. In search of accurate PD prediction, we propose a flexible yet easy-to-interpret default-prediction single-index hazard model (DSI). By applying it to a comprehensive U.S. corporate bankruptcy database we constructed, we discover an interesting V-shaped relationship, indicating a violation of the common linear hazard specification. Most importantly, the single-index hazard model passes the Hosmer-Lemeshow goodness-of-fit calibration test while neither does a state-of-the-art linear hazard model in finance nor a parametric class of Box-Cox transformation survival models. In an economic value analysis, we find that this may translate to as much as three times of profit compared to the linear hazard model. In model estimation, we adopt a penalized-spline approximation for the unknown function and propose an efficient algorithm. With a diverging number of spline knots, we establish consistency and asymptotic theories for the penalized-spline likelihood estimators. Furthermore, we reexamine the distress risk anomaly, that is, higher financially distressed stocks deliver anomalously lower excess returns. Based on the PDs from the proposed single-index hazard model, we find that the distress risk anomaly has weakened or even disappeared during the extended period. [ABSTRACT FROM AUTHOR]

By tuning the amount of the Se precursors during the synthesis, orthorhombic PdSe2, cubic Pd17Se15, and monoclinic Pd7Se2 nanoparticles are synthesized, which show phase-dependent electrocatalysis for the ethanol oxidation reaction. This work advances the controllable synthesis of transition metal selenides and inspires their applications in electrocatalysis. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru)‐ and iridium (Ir)‐based nanomaterials have always been regarded as efficient electrocatalysts for oxygen evolution reaction (OER) in acidic electrolytes. Herein, we develop a facile dodecylamine‐assisted hydrothermal synthesis for producing carbon‐supported IrRu alloy nanoparticles with controllable Ir/Ru ratios and ultrafine sizes towards high‐efficiency OER and overall water electrolysis. In this strategy, the dodecylamine that serves as a capping and reducing agent enables the final IrRu alloy nanoparticles to possess average sizes <3 nm and high degree of dispersion on carbon substrate. By combining high OER activity of Ru with high acidic robustness of Ir, the as‐prepared IrRu/C nanoparticles at a suitable Ir/Ru ratio of 1/3 show good activity and durability for the OER electrocatalysis and overall water splitting. In specific, the Ir1Ru3/C catalyst exhibits the lowest overpotential of 302 mV at the current density of 10 mA cm−2 and the highest mass activity of 120.5 mA mg−1 at 1.532 V for OER in 0.5 M H2SO4 electrolyte. In addition, a two‐electrode acidic electrolyzer assembled with Ir1Ru3/C at anode and commercial Pt/C at cathode (Pt/C|| Ir1Ru3/C) exhibits a low cell voltage of 1.44 V for achieving the current density of 10 mA cm−2, along with a satisfied 20h durability. [ABSTRACT FROM AUTHOR]

A template-directed synthesis of one-dimensional hexagonal PdTe nanowires using Te nanowires as a template through a two-step hydrothermal process is developed, which exhibit excellent mass activity of 4.4 A mg Pd -1 for ethanol electrooxidation in an alkaline medium. This work enriches the controlled synthesis of one-dimensional noble metal chalcogenide nanomaterials.

The cation-exchange strategy has shown great potential to create a large variety of inorganic nanostructures. We herein report the cation-exchange reactions between CdSe nanocrystals and Pd 2+ cations in different solvent environments and identify three features not sufficiently noticed before: (i) the exchange between Cd 2+ and Pd 2+ cations could be fully achieved in both aqueous and organic solvents and is also independent of its parent CdSe crystal structures; (ii) the exchange between Cd 2+ and Pd 2+ cations in aqueous solvent results in amorphous Pd-Se exchanged products, while in organic solvent, it leads to a cubic Pd 17 Se 15 phase; and (iii) the exchanged Pd 17 Se 15 product exhibits better electrocatalysis for ethanol oxidation reaction in an alkaline medium relative to its amorphous counterpart and the commercial Pd/C catalyst.