One of the emerging issues in solving the electronic waste problem is to address the growing amount of end-of-life Liion battery (LIB) waste. In this work, the regeneration of LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM 111) cathode active materials from end-of-life LIBs was successfully carried out via an easy, fast, and environmentally friendly recycling process that comprised three main stages, i.e., ascorbic acid leaching, oxalate coprecipitation process, and heat treatment. Ascorbic acid was able to leach Li, Ni, Co, and Mn ions from the spent NCM 111 cathode material with a relatively high leaching efficiency up to 90%. The following oxalic acid coprecipitation method has effectively recovered the transition metal ions in the leachate in the form of the metal oxalates MC 2 O 4 • 2H 2 O (M = Ni, Mn, and Co), as confirmed by the result of X-ray diffraction characterization. The quantitative analysis of metal ions using X-ray fluorescence revealed that the ratio of Ni, Co, and Mn in the precipitate was approximately 1:1:1, with a slightly lower amount of Mn. Regeneration of NCM 111 via the heat treatment of metal oxalates at temperatures of 800−950 °C successfully reproduced the material (R-NCM) with an R3m hexagonal-layered structure, which could be reemployed as the cathode in LIBs. Charge−discharge characterization of the as-fabricated LIB at 2.5−4.3 V revealed that the battery with the R-NCM cathode synthesized at 900 °C exhibited a slightly higher initial specific discharge capacity (164.9 mAh/g at 0.2 C) than that of commercial NCM (157.4 mAh/g at 0.2 C). Moreover, the Li-ion battery also showed a very stable performance with a capacity retention of 91.3% after 100 cycles at 0.2 C.

The simultaneous UV and first NIR absorption of the CDs/PVA composite could be maintained up to 200 °C, with minimum PL changes.

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Tunable emissive solid-state carbon nanoparticles (CNPs) have been successfully synthesized by a facile synthesis through microwave irradiation.

We report the catalyzed atomic layer deposition (ALD) of silicon oxide using SiCl, HO, and various alkylamines. The density functional theory (DFT) calculations using the periodic slab model of the SiO surface were performed for the selection of alternative Lewis base catalysts with high catalytic activities. During the first half-reaction, the catalysts with less steric hindrance such as pyridine would be more effective than bulky alkylamines despite lower nucleophilicity. On the other hand, during the second half-reaction, the catalysts with a high nucleophilicity such as triethylamine (EtN) would be more efficient because the steric hindrance is less critical. The in situ process monitoring shows that the calculated atomic charge is a good indicator for expecting the catalyst activity in the ALD reaction. The use of EtN in the second half-reaction was essential to improving the growth rate as well as the step coverage of the film because the EtN-catalyzed process deposited a SiO film with a step coverage of 98% that is better than 93% of the pyridine-catalyzed process. The adsorption of pyridine, ammonia (NH), or trimethylamine (MeN) salts was more favorable than that of EtN, n-PrN, or PrN salts. Therefore, EtN was expected to incorporate less amine salts in the film as compared to pyridine, and the compositional analyses confirmed that the concentrations of Cl and N by the EtN-catalyzed process were significantly lower than those by the pyridine-catalyzed process.