Despite the tremendous efforts devoted to enhancing the activity of oxygen evolution reaction (OER) catalysts, there is still a huge challenge to deeply understand the electronic structure characteristics of transition metal oxide to guide the design of more active catalysts. Herein, Fe3O4 with oxygen vacancies (Fe3O4‐Vac) was synthesized via Ar ion irradiation method and its OER activity was greatly improved by properly modulating the electron density around Fe atoms. The electron density of Fe3O4‐Vac around Fe atoms increased compared to that of Fe3O4 according to the characterization of synchrotron‐based X‐ray absorption near‐edge structure (XANES), extended X‐ray absorption fine structure (EXAFS) spectra, and density functional theory (DFT) calculation. Moreover, the DFT results indicate the enhancement of the desorption of HOO* groups which significantly reduced the OER reaction barrier. Fe3O4‐Vac catalyst shows an overpotential of 353 mV, lower than that of FeOOH (853 mV) and Fe3O4 (415 mV) at 10 mA cm−2, and a low Tafel slope of 50 mV dec−1 in 1 M KOH, which was even better than commercial RuO2 at high potential. This modulation approach provides us with valuable insights for exploring efficient and robust water‐splitting electrocatalysts.

Nonvolatile charge trap memory is an important part of the continuous development of information technology. As a 2-dimensional (2D) material with fantastic physical characteristics, molybdenum disulfide (MoS 2 ) has been receiving extensive attention for its potential applications in electronic devices. However, while various attempts have been made to devise its charge-trap gate stack, it's still impossible to avoid a certain performance degradation. Here, a MoS 2 -based nonvolatile charge trapping memory device with a charge-trap gate stack formed by implanting N ions into SiO 2 is reported. The fabricated N-implanted memory devices with the energy of 6.5 keV and the dose of 1 × 10 15 ions cm −2 exhibit a high on/off current ratio up to 10 7 , a large memory window of 9.1 V, and a high program/erase speed of 10/100 µs. Moreover, the memory device shows an excellent cycling endurance of more than 10 4 cycles. By combining the MoS 2 channel with the N-implanted chargetrap gate stack, this research opens up a fascinating field of nonvolatile charge trap memory devices.

Engineering materials for nuclear reactors exposed to high-dose irradiation breed various radiation damage, leading to performance degradation of materials, which seriously limits the application of materials in the future advanced nuclear reactors. Tungsten-based materials applied in future nuclear reactors have to withstand not only the attack of high-energy neutron and plasma, but also the repeated impact of steady-state or even transient thermal load. Researches in the past decades have proved that tailored nanostructure have advantage in annihilating radiation defects. With the rapid development of nanostructured tungsten, probing radiation application of nanostructured tungsten is of great significance in promoting the development of novel radiation-resistant materials. Herein, the development status of three kinds of nanostructured tungsten namely nanocrystalline, nanofilm and nanoporous tungsten designed for radiation tolerance and the performance enhancement mechanism of diverse nanostructure in irradiation environment is reviewed. Finally, future perspectives and technical challenges are discussed, to inspire more creative designs of novel nanostructured tungsten for radiation tolerance.

Exploring highly active, enduringly stable, and low-cost oxygen evolution reaction catalysts continues to be a dominant challenge to commercialize renewable electrochemical water-splitting technology. High-active and earth-abundant cobalt phosphides are recently considered as promising candidates. However, the poor inherent electron transfer efficiency and instability hinder its further development. In this work, a novel approach was demonstrated to effectively synthesize Co2P nanoparticles wrapped in amorphous porous carbon framework (Co2P/C). Benefiting from extremely high specific surface area of porous carbon, plenty of active sites were adequately exposed. Meanwhile, unique anchoring structure between Co2P nanoparticles and amorphous carbon outerwear insured high charge transfer efficiency and superior stability of Co2P/C. Due to these favorable properties, low overpotential of 281 mV at 10 mA cm−2 and Tafel slope of 69 mV dec−1 were achieved in resultant Co2P/C catalyst. More significantly, it only exhibited a negligible overpotential increase after 30 h stability test, and these performances entirely preceded commercial RuO2 benchmark. In summary, we proposed a simple and feasible strategy to prepare metal phosphides wrapped with amorphous porous carbon outerwear for efficient and durable electrochemical water oxidation.

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