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A correction to the article "BMC Palliat Care 23, 136 (2024)" in the BMC Palliative Care issue discusses the addition of equal contribution acknowledgment for the first and second authors, Guojuan Chen and Xiaoling Zhang.

For high performance supercapacitors, novel hierarchical yolk-shell α-Ni(OH)2/Mn2O3 microspheres were controllably synthesized using a facile two-step method based on the solvothermal treatment. The unique α-Ni(OH)2 based yolk-shell microstructures decorated with numerous interconnected nanosheets and the heterocomposition features can synergistically enhance reactive site exposure and electron conduction within the microspheres, facilitate charge transfer between electrolyte and electrode materials, and release structural stress during OH− chemisorption/desorption. Moreover, the Mn2O3 sediments distributed over the α-Ni(OH)2 microspheres can serve as an effective protective layer for electrochemical reactions. Consequently, when tested in 1 mol·L−1 KOH aqueous electrolyte for supercapacitors, the yolk-shell α-Ni (OH)2/Mn2O3 microspheres exhibited a considerably high specific capacitance of 2228.6 F·g−1 at 1 A·g−1 and an impressive capacitance retention of 77.7% after 3000 cycles at 10 A·g−1. The proposed α-Ni(OH)2/Mn2O3 microspheres with hetero-composition and unique hierarchical yolk-shell microstructures are highly promising to be used as electrode materials in supercapacitors and other energy storage devices. [ABSTRACT FROM AUTHOR]

Ni-rich LiNi x Co y Mn 1- x - y O 2 (0.5 < x < 1) cathode materials have attracted considerable interest due to their high energy density and low cost. However, they are subject to capacity fading during cycling, such as structural degradation and irreversible oxygen release, especially under high voltage. Herein, we report an in situ epitaxial growth strategy to construct a thin layer of LiNi 0.25 Mn 0.75 O 2 on the surface of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811). Both of them share the same crystal structure. Interestingly, the LiNi 0.25 Mn 0.75 O 2 layer can be electrochemically converted into a stable spinel LiNi 0.5 Mn 1.5 O 4 (LNM) due to the Jahn-Teller effect under high voltage cycling. The derived LNM protective layer can effectively alleviate the harmful side reactions between the electrode and electrolyte and suppress oxygen release as well. Furthermore, the coating LNM layer can enhance Li + ion diffusion due to its three-dimensional channels for Li + ion transport. When used as half-cells with lithium as the anode, NCM811@LNM-1% realizes a large reversible capacity of 202.4 mA h g -1 at 0.5 C, with high capacity retention of 86.52% at 0.5 C and 82.78% at 1 C, respectively, after 200 cycles in the voltage range of 2.8-4.5 V. Moreover, the assembled pouch full-cell with NCM811@LNM-1% as cathode and commercial graphite as an anode can deliver 11.63 mA h capacity with a high capacity retention of 80.05% after 139 cycles in the same voltage range. This work demonstrates a facile approach to the fabrication of NCM811@LNM cathode materials for enhancing performance in lithium-ion batteries under high voltage, rendering its promising applications.

Cation-disordered rock-salt cathode materials are featured by their extraordinarily high specific capacities in lithium-ion batteries primarily contributed by anion redox reactions. Unfortunately, anion redox reactions can trigger oxygen release in this class of materials, leading to fast capacity fading and major safety concern. Despite the capability of absorbing structural distortions, high-ratio d 0 transition-metal cations are considered to be unfavorable in design of a new cation-disordered rock-salt structure because of their electrochemically inactive nature. Herein, we report a new cation-disordered rock-salt compound of Li 1.2 Ti 0.6 Mn 0.2 O 2 with the stoichiometry of Ti 4+ as high as 0.6. The capacity reducing effect by the low-ratio active transition-metal center can be balanced by using a Mn 2+ /Mn 4+ two-electron redox couple. The strengthened networks of strong Ti-O bonds greatly retard the oxygen release and improve the structural stability of cation-disordered rock-salt cathode materials. As expected, Li 1.2 Ti 0.6 Mn 0.2 O 2 delivers significantly improved electrochemical performances and thermal stability compared to the low-ratio Ti 4+ counterpart of Li 1.2 Ti 0.4 Mn 0.4 O 2 . Theoretical simulations further reveal that the improved electrochemical performances of Li 1.2 Ti 0.6 Mn 0.2 O 2 are attributed to its lower Li + diffusion energy barrier and enhanced unhybridized O 2p states compared to Li 1.2 Ti 0.4 Mn 0.4 O 2 . This concept might be helpful for the improvement of structural stability and electrochemical performances of other cation-disordered rock-salt metal oxide cathode materials.