Owing to their natural abundance, the low potential, and the low cost of potassium, potassium-ion batteries are regarded as one of the alternatives to lithium-ion batteries. In this work, we successfully fabricated a FeP/C composite, a novel electrode material for PIBs, through a simple and productive high-energy ball-milling method. The electrode delivers a reversible capacity of 288.9 mA•h•g −1 (2nd) at a discharge rate of 50 mA g −1 , which can meet the future energy storage requirements. Density functional theory calculations suggest a lower diffusion barrier energy of K + than Na + , which allows faster K + diffusion in FeP.

The equilibrium geometries and energies of neutral BeSi(n) (n = 2-10) species and their anions have been studied at the highest level of Gaussian-3 (G3) theory. The results reveal that the ground-state structures of these clusters are Be-encapsulated in silicon cages with n >or= 8. The reliable adiabatic electron affinities of BeSi(n) have been predicted to be 1.68 eV for BeSi(2), 1.87 eV for BeSi(3), 2.33 eV for BeSi(4), 2.29 eV for BeSi(5), 2.11 eV for BeSi(6), 2.37 eV for BeSi(7), 2.95 eV for BeSi(8), 2.74 eV for BeSi(9), and 1.92 eV for BeSi(10). The dissociation energies of Be atom from BeSi(n), Si atom from BeSi(n), and Si atom from Si(n) clusters have also been calculated, respectively, to examine relative stabilities. The trend of stability of BeSi(n) changed with n is converse to that of Si(n) when n or= 8, the encapsulated Be atom in silicon cages not only results in an identical trend for stability of BeSi(n) and Si(n) but also improves the stability of Si(n) clusters.

Reasonable modification of ancillary ligands for Pt(ii) complexes can effectively improve the quantum efficiency and strengthen the rigidity of luminescent materials in organic light-emitting diodes.

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High‐energy‐density and low‐cost lithium‐ion batteries are sought to meet increasing demand for portable electronics. In this study, a cobalt‐free Li(Li0.17Ni0.17Fe0.17Mn0.49)O2 (LNFMO) cathode material is chosen, owing to the reversible anionic redox couple O2−/O−. The aim is to elucidate the Fe‐substitution function and oxygen redox mechanism of experimentally synthesized Li(Li0.16Ni0.19Fe0.18Mn0.46)O2 by DFT. The redox processes of cobalt‐containing Li(Li0.17Ni0.17Co0.17Mn0.49)O2 (LNCMO) are compared with those of LNFMO. Redox couples including Ni2+/Ni3+/Ni4+, Fe3+/Fe4+ or Co3+/Co4+, and O2−/O− are found, confirmed by a X‐ray photoelectron spectroscopy, and explained by redox competition between O and transition metals. In LNFMO and LNCMO, O ions with an Li‐O‐Li configuration readily participate in oxidation, and the most active O ions are coordinated to Mn4+ and Li+. Oxidation of O in LNCMO is triggered earlier, along with that of Co. Fe substitution activates O ions, contributes additional oxygen redox charge compensation of 0.44 e per formula unit, avoids concentrated accumulation of oxygen oxidation, and improves structural stability. This work provides new scope for designing cobalt‐free, low‐cost, and higher‐energy‐density cathode materials for Li‐ion batteries.