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Highlights: Plasma-assisted phosphorization has been used to prepare defect-rich metal phosphides. The p-NiCoP/NCF@CC shows high activities and excellent stability for the hydrogen evolution reaction and the oxygen evolution reaction. The p-NiCoP/NCF@CC shows great potential for overall water splitting. This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in alkaline media. Specifically, the nitrogen-doped carbon nanofiber-supported Ni-doped CoP3 with rich P defects (Pv·) on the carbon cloth (p-NiCoP/NCFs@CC) is synthesized through a plasma-assisted phosphorization method. The p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the OER. It only needs overpotentials of 107 and 306 mV to drive 100 mA cm−2 for the HER and the OER, respectively. Its catalytic activities are higher than those of other catalysts reported recently. The high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural features. The density functional theory calculation indicates that the Pv· richness, the Ni doping, and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER process. This gives the p-NiCoP/NCFs@CC with the high activities for the HER and the OER. When used in alkaline water electrolyzers, the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting. [ABSTRACT FROM AUTHOR]

Herein, Co/CoO heterojunction nanoparticles (NPs) rich in oxygen vacancies embedded in mesoporous walls of nitrogen‐doped hollow carbon nanoboxes coupled with nitrogen‐doped carbon nanotubes (P–Co/CoOV@NHCNB@NCNT) are well designed through zeolite‐imidazole framework (ZIF‐67) carbonization, chemical vapor deposition, and O2 plasma treatment. As a result, the three‐dimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P–Co/CoOV@NHCNB@NCNT, and they display exceedingly good electrocatalytic performance for oxygen reduction reaction (ORR, halfwave potential [EORR, 1/2 = 0.855 V vs. reversible hydrogen electrode]) and oxygen evolution reaction (OER, overpotential (ηOER, 10 = 377 mV@10 mA cm−2), which exceeds that of the commercial Pt/C + RuO2 and most of the formerly reported electrocatalysts. Impressively, both the aqueous and flexible foldable all‐solid‐state rechargeable zinc–air batteries (ZABs) assembled with the P–Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long‐term cycling stability. First‐principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity, reduces reaction energy barriers, and accelerates reaction kinetics rates. This work opens up a new avenue for the facile construction of highly active, structurally stable, and cost‐effective bifunctional catalysts for ZABs. [ABSTRACT FROM AUTHOR]

This work reports the use of the metal‐support interaction strengthening through defect engineering and single atom adsorption to the supports to increase the catalytic activities of metals. Specifically, the plasma treated TiO2 nanowires with the Ir nanoparticle growth and the Sr single atom adsorption (the Ir@Sr‐p‐TiO2 NWs) are synthesized and demonstrated to be efficient catalysts for OER and HER. They only need overpotentials of 250 and 32 mV to drive 10 mA cm−2 for OER and HER, respectively. Their OER and HER activities are much higher than the commercial IrO2 and Pt/C. The high activities of the Ir@Sr‐p‐TiO2 NWs mainly arise from the strengthened metal‐support interactions between the Ir nanoparticles and the p‐TiO2 NWs, achieved by the plasma generated oxygen defects (Vo·) and the Sr adsorption on the p‐TiO2 NWs. Analysis and DFT calculations indicate that the Vo· and Sr adsorption can promote the charge transfer from the p‐TiO2 NWs to the Ir nanoparticles, optimizing the adsorptions of the OER and HER intermediates on the O‐ and H‐covered Ir nanoparticles. Additionally, the strong metal‐support interactions can increase the stabilities of the Ir NPs against the chemical corrosions, increasing the OER and HER durabilities of the Ir@Sr‐p‐TiO2 NWs. [ABSTRACT FROM AUTHOR]

The carbon nanotubes (CNTs) supported amorphous Sb doped substoichiometric tin dulfide (Sb─SnSx) with a carbon coating (the C/Sb─SnSx@CNTs‐500) is reported to be an efficient anode material for K+ storage. The formation of the C/Sb─SnSx@CNTs‐500 is simply achieved through the thermally induced desulfurization of tin sulfide via a controlled annealing of the C/Sb─SnS2@CNTs at 500 °C. When used for the K+ storage, it can deliver stable reversible capacities of 406.5, 305.7, and 238.4 mAh g−1 at 0.1, 1.0, and 2.0 A g−1, respectively, and shows no capacity drops when potassiated/depotassiated at 1.0 and 2.0 A g−1 for >3000 and 2400 cycles, respectively. Even at 10, 20, and 30 A g−1, it can still deliver stable reversible capacities of 138.5, 85.1, and 73.8 mAh g−1, respectively. The unique structure, which combines the advantageous features of carbon integration/coating, metal doping, and desulfurization‐induced amorphous structure, is the main origin of the high performance of the C/Sb─SnSx@CNTs‐500. Specifically, the carbon integration/coating can increase the electric conductivity and stability of the C/Sb─SnSx@CNTs‐500. The density function theory calculation indicates that the Sb doping and the desulfurization can facilitate the potassiation and increase the electric conductivity of Sb─SnSx. Additionally, the desulfurization can increase the K+ diffusivity in Sb─SnSx. [ABSTRACT FROM AUTHOR]

The development of sodium‐ion battery (SIB) anodes is still hindered by their rapid capacity decay and poor rate capabilities. Although there have been some new materials that can be used to fabricate stable anodes, SIBs are still far from wide applications. Strategies like nanostructure construction and material modification have been used to prepare more robust SIB anodes. Among all the design strategies, the hollow structure design is a promising method in the development of advanced anode materials. In the past decade, research efforts have been devoted to modifying the synthetic route, the type of templates, and the interior structure of hollow structures with high capacity and stability. A brief introduction is made to the main material systems and classifications of hollow structural materials first. Then different morphologies of hollow structural materials for SIB anodes from the latest reports are discussed, including nanoboxes, nanospheres, yolk shells, nanotubes, and other more complex shapes. The most used templates for the synthesis of hollow structrual materials are covered and the perspectives are highlighted at the end. This review offers a comprehensive discussion of the synthesis of hollow structural materials for SIB anodes, which could be potentially of use to research areas involving hollow materials design for batteries. [ABSTRACT FROM AUTHOR]

Resonance Raman spectra and absolute differential Raman cross-sections have been measured for CdSe nanocrystals in both the wurtzite and zincblende crystal forms at four excitation wavelengths from 457.9 to 514.5 nm. The frequency and bandshape of the longitudinal optical (LO) phonon fundamental is essentially identical for both crystal forms at each excitation wavelength. The LO phonon overtone to fundamental intensity ratio appears to be slightly higher for the wurtzite form, which may suggest slightly stronger exciton-phonon coupling from the Fröhlich mechanism in the wurtzite form. The LO fundamental Raman cross-sections are very similar for both crystal forms at each excitation wavelength. © 2012 Elsevier B.V. All rights reserved.