Developing efficient and stable non‐noble electrocatalysts for the oxygen evolution reaction (OER) remains challenging for practical applications. While nickel–iron layered double hydroxides (NiFe‐LDH) are emerging as prominent candidates with promising OER activity, their catalytic performance is still restricted by the limited active sites, poor conductivity and durability. Herein, hierarchical nickel–iron–cobalt LDH nanosheets/carbon fibers (NiFeCo‐LDH/CF) are synthesized through solvent‐thermal treatment of ZIF‐67/CF. Extended X‐ray adsorption fine structure analyses reveal that the Co substitution can stabilize the Fe local coordination environment and facilitate the π‐symmetry bonding orbital in NiFeCo‐LDH/CF, thus modifying the electronic structures. Coupling with the structural advantages, including the largely exposed active surface sites and facilitated charge transfer pathway ensured by CF, the resultant NiFeCo‐LDH/CF exhibits excellent OER activity with an overpotential of 249 mV at 10 mA cm−1 as well as robust stability over 20 h.

A hybrid of N-doped carbon encapsulated ultrasmall Mo2C nanodots on Ti3C2Tx MXene exhibits excellent HER performance in the entire pH range.

In situ XRD examinations demonstrate significant effects of a Li2MnO3 coating on suppressing structural degradation during charging/discharging of Ni-rich cathode materials for enhanced cycling stability.

Although 2D Ti3C2Tx is a good candidate for supercapacitors, the restacking of nanosheets hinders the ion transport significantly at high scan rates, especially under practical mass loading (>10 mg cm−2) and thickness (tens of microns). Here, Ti3C2Tx‐NbN hybrid film is designed by self‐assembling Ti3C2Tx with 2D arrays of NbN nanocrystals. Working as an interlayer spacer of Ti3C2Tx, NbN facilitates the ion penetration through its 2D porous structure; even at extremely high scan rates. The hybrid film shows a thickness‐independent rate performance (almost the same rate capabilities from 2 to 20 000 mV s−1) for 3 and 50 µm thick electrodes. Even a 109 µm thick Ti3C2Tx‐NbN electrode shows a better rate performance than 25 µm thick pure Ti3C2Tx electrodes. This method may pave a way to controlling ion transport in electrodes composed of 2D conductive materials, which have potential applications in high‐rate energy storage and beyond.

Moreover, the practical application of FeCO3 NR@Ti3C2 anode material is further primarily evaluated by coupling with a commercial Ni-rich LiNi0.8Co0.1Mn0.1O2 (marked as NCM811) cathode material. SEM image of NCM811 particles...

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF/ MS), size exclusion chromatography (SEC), and dilute solution viscometry were used to analyze the structure of three generations of Astromol (trademark of DSM) dendrimers having cyano end groups. The molecular weights, the defect contents, and the structures of the "imperfect" dendrimers were determined by MALDI/TOF/MS analysis with fractions collected using a SEC fraction collector. The peak broadening observed for these materials in SEC was studied by adding different co-solvents to the SEC mobile phase. The hydrodynamic radius of the dendrimers was measured both by dilute solution viscometry and by SEC universal calibration. Our radii data are comparable to previously published results for these dendrimers obtained by neutron scattering and support the opinion that dendrimers have compact spherical structures.

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