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Developing an efficient and stable hydrogen evolution catalyst is the core issue to promoting the wide application of hydrogen energy. Herein, we report a novel strategy to design a self-supported ...

Oxygen evolution reaction (OER) plays an important role in various renewable energy systems. Owing to its complex four-electron redox process, the OER process with sluggish kinetics often requires electrocatalysts to reduce the overpotential and promote the reaction rate. Herein, we have proposed an “all-in-one” strategy to synthesize mutil-elemental perovskite oxides nanofibers (NFs) with hollow and porous structures by using electrospinning technology and Ostwald ripening approach. The hollow La0.7Sr0.3Co0.25Mn0.75O3 nanofibers (LSCM NFs) consist of large amounts of building block La0.7Sr0.3Co0.25Mn0.75O3 nanoparticles (LSCM NPs), forming the unique architecture and the morphologies can be engineering by adjusting the calcination temperatures and the heating rates. Notably, the hollow LSCM NFs prepared at 800 °C and 10 °C min−1 demonstrated the excellent electrocatalytic performance, with overpotential of 340 mV at current density of 10 mA cm−2 and Tafel slope of 111 mV dec−1, as well as the long-term stability in alkaline electrolyte. The hollow NFs architectures exhibited a large specific surface area, a high porosity and a large inner space, which are beneficial for the OER, reducing the overpotentials and accelerating the electrode kinetics.

The appropriate catalyst model with a precisely designed interface is highly desirable for revealing the real active site at the atomic level. Herein, we report a proof-of-concept strategy for creating an exposed and embedding interface model by constructing a unique Co

The key issue in efficient electrochemical detection of trace heavy metal ions (HMIs) is to design hierarchical nanostructure electrodes with high sensitivity and low detection limit. In this study, bimetallic PtAu alloy nanoparticles (PtAuNPs) with uniform size and distribution were constructed in electrospun carbon nanofibers (CNFs) by combining an electrospinning procedure and an in situ thermal reduction process. The PtAu/CNF membrane can be directly used as a sensor electrode for simultaneous detection of trace Cd2+, Pb2+, and Cu2+ by square wave anodic stripping voltammetry (SWASV). The prepared PtAu/CNF membrane is capable of simultaneously detecting Cd2+, Pb2+, and Cu2+ with a sensitivity of 0.10 μM and correlation coefficients of 0.976, 0.993, and 0.976, respectively, indicating high sensitivity and good linear relation. The excellent sensitivity and low detection limit for HMI detection were ascribed to the high conductivity of CNFs, fast response of PtAu alloy NPs, and high specific surface area of the hybrid structure. The present research provides a convenient and efficient way to construct new sensors for simultaneous trace detection of HMIs.

A concept of experiment to tune the two-dimensional MoS2 into VMo2S4 via thermodynamic driven phase engineering by combining the facile electrospinning technology and S-vapor assisted graphitization process has been demonstrated. Compared to V doped MoS2 nanosheets, the VMo2S4 nanosheets show a superior oxygen evolution reaction (OER) activity in alkaline electrolyte, reaching a current density of 10 mA cm−2 at overpotential of 295 mV with Tafel slope of 97 mV dec−1. The VMo2S4 nanosheets also show superior water splitting activity with 10 mA cm−2 at a cell voltage of 1.65 V. The theoretical and experimental results reveal that the V introduction into interplane of MoS2 leads to the significant decrease in the energy barrier for *OOH formation (0.99 eV), thus suggesting the improved transformation from *OOH to O2.

1D hollow nanostructures combine the advantages of enhanced surface-to-volume ratio, short transport lengths, and efficient 1D electron transport, which can provide more design ideas for the preparation of highly active oxygen evolution (OER) electrocatalysts. A unique architecture of dual-phase octahedral CoMn2 O4 /carbon hollow nanofibers has been prepared via a two-step heat-treatment process including preoxidation treatment and Ostwald ripening process. The hollow and porous structures provide interior void spaces, large exposed surfaces, and high contact areas between the nanofibers and electrolyte and the morphology can be engineered by adjusting the heating conditions. Due to the intimate electrical and chemical coupling between the oxide nanocrystals and integrated carbon, the dual-phase octahedral CoMn2 O4 /carbon hollow nanofibers exhibit excellent OER activity with overpotentials of 337 mV at current density of 10 mA cm-2 and Tafel slope of 82 mV dec-1 . This approach will lead to the new perception of design issue for the nanoarchitecture with fine morphology, structures, and excellent electrocatalytic activity.