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Abstract Nowadays nickel-rich LiNi x Co y Mn 1-x-y O 2 (0.5 < x < 1) cathode materials attract great research interests due to their high specific capacity in lithium ion batteries. However, poor cycling performance and serious safety concerns trade off their benefits. Here, we present an effective etching-induced coating strategy for surface modification of LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode materials by LiAlO 2. Hydrolysis of AlCl 3 creates H+ to etch the hydroxide precursor of LiNi 0.8 Co 0.1 Mn 0.1 O 2 and to induce oriented deposition of Al(OH) 3 layer on surface of the hydroxide precursor, which is transformed into uniform γ-LiAlO 2 coating on the LiNi 0.8 Co 0.1 Mn 0.1 O 2 particles after the subsequent lithium impregnating and annealing. The 2.2 wt% LiAlO 2 -coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode delivers a high rate capacity of 135.2 mAh g−1 at 10 C and long cyclability with capacity retention of 85.8% after 200 cycles at 0.5 C. In addition, the thermal stability of LiAlO 2 -coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 is significantly improved. The enhanced battery performances are due to partial Al3+ doping and Li+ conductive LiAlO 2 coating layer that provides well-connected networks for Li+ transport, improves the structural stability and prevents core materials from the attack by side products. Graphical abstract The detailed etching-induced coating strategy for the synthesis of LiAlO 2 -coated NCM811 materials. Image 1 Highlights • The etching-induced coating strategy was designed to prepare LiAlO 2 -coated NCM811. • The modified NCM811 exhibits better rate and cycle performance. • The modified NCM811 displays smaller overpotential especially at high rate. • The coating of LiAlO 2 significantly improves the thermal stability of NCM811. [ABSTRACT FROM AUTHOR]

Deposition technology of transparentconducting oxide (TCO) thinfilms is critical for high performance of optoelectronic devices.Solution-based fabrication methods can result in substantial costreduction and enable broad applicability of the TCO thin films. Herewe report a simple and highly effective solution process to fabricateindium–tin oxide (ITO) thin films with high uniformity, reproducibility,and scalability. The ITO films are highly transparent (90.2%) andconductive (ρ = 7.2 × 10–4Ω·cm)with the highest figure of merit (1.19 × 10–2Ω–1) among all the solution-processed ITOfilms reported to date. The high transparency and figure of merit,low sheet resistance (30 Ω/sq), and roughness (1.14 nm) arecomparable with the benchmark properties of dc sputtering and canmeet the requirements for most practical applications. [ABSTRACT FROM AUTHOR]

• A PVP-bridged coating strategy was designed to prepare the LMR@γ-LAO composite. • γ-LiAlO 2 coating layer leads to a higher Li+ diffusion coefficient of the cathode. • γ-LiAlO 2 coating layer enhances the thermal stability of the cathode. • DFT calculation proves a lower Li+ diffusion energy barrier in γ-LiAlO 2. Li-rich layered materials have been considered as promising cathode materials for next-generation lithium-ion batteries due to their high capacity (≥250 mAh g−1). Unfortunately, this type of cathode material still suffers from intrinsic deficiencies of capacity fading and side reactions. Surface coating with a protective layer can resolve the above problems to some extent, whereas normal coating strategies still suffer from process complexity and are difficult to prevent phase separation that leads to the formation of an independent miscellaneous phase. Herein, we report an effective PVP-bridged coating method, in which the PVP molecules can bridge the gap between the coating shell and the electrode material core through hydrogen bonding and functional groups. Utilizing this strategy, a uniform Li-ion conductor γ-LiAlO 2 nanolayer with a thickness of 7 nm is successfully formed on the surface of the Li 1.2 Ni 0.182 Co 0.08 Mn 0.538 O 2 cathode material, which leads to an excellent rate capability (177.0 mAh g−1 delivered at 5 C) and superior cycling stability (89.3% capacity retention achieved after 100 cycles at 10 C) for the composite material. Furthermore, the exothermic reaction for the composite material takes place at a higher temperature (234.1 °C) relative to the uncoated sample (220.9 °C), implying its improved thermal stability. Galvanostatic intermittent titration technique and density functional theory calculation demonstrate a higher Li+ diffusion coefficient for the γ-LiAlO 2 coated sample and a lower Li+ diffusion energy barrier in γ-LiAlO 2. Based on the promising results, the PVP-bridged coating strategy presented in this study provides a new perspective in material design towards high-performance Li-rich cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]