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Transition-metal selenides is regarded as promising electrode materials due to their superior electrochemical performances for supercapacitors. In this study, nanorod-like hybrid of Ni0.85Se@Cu2-xSe on Ni-foam substrate is successfully synthesized via...

Designing electrocatalysts for the water oxidation reaction (WOR) and the methanol oxidation reaction (MOR) using earth-abundant elements is crucial for the development of water electrolyzers and direct methanol fuel cells. We report the synthesis of nickel phosphide nanospheres with different crystallinities (Ni 2 P-H, Ni 2 P-L, and Ni-P-a) by reacting Ni-based metal−organic frameworks and P 4 solvothermally. All the nickel phosphide nanospheres synthesized are active toward WOR and MOR, and Ni 2 P-L, with amorphous/crystalline heterostructures, shows the best electrocatalytic performance. For WOR, the overpotential at 10 mA cm −2 for Ni 2 P-L on Ni foam is 300 mV in 1 M KOH (loading 0.8 mg Ni+P cm −2 ), and the Tafel slope is ∼86.4 mV dec −1 . For MOR, Ni 2 P-L on carbon paper has the highest current density of 427.0 mA mg −1 at 1.74 V RHE in 1 M KOH + 0.5 M CH 3 OH. Structural characterizations and electrochemical kinetic studies suggest that the high electrocatalytic activity of Ni 2 P-L originates from the abundant electrochemically active sites exposed owing to the amorphous phase and the electron interaction between Ni and P, which tunes the WOR intermediate (OH*) adsorption energy. Conversion of phosphides to (oxy)hydroxides at the surface is also observed after long-term WOR.

A descriptor, SVWG (principal component scores vector of WHIM (weighted holistic invariant molecular index) descriptors and GETWAY (GEometry, Topology, and Atom‐Weights AssemblY) descriptors), was derived from a principal component analysis of a matrix of two structural variables of coded amino acid. SVWG scales were then applied in three panels of peptide quantitative structure activity relationship (QSAR) that were molded by partial least squares regression. The obtained models with the correlation coefficient (Rcum2) and cross‐validation correlation coefficient (QLOO2) were 0.893 and 0.830 for angiotensin‐converting enzyme inhibitors, 0.990 and 0.968 for antimicrobial peptides, and 0.955 and 0.908 for oxytocin, respectively. Satisfactory results showed that information related to biological activity can be systemically expressed by SVWG scales, which may be a useful structural expression methodology for study on peptide QSAR. Copyright © 2012 John Wiley & Sons, Ltd.

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