Improved electrochemical performance of SiO2-coated Li-rich layered oxides-Li1.2Ni0.13Mn0.54Co0.13O2

Lithium-rich layered oxides (LLOs) such as Li1.2Ni0.13Mn0.54Co0.13O2 are suitable cathode materials for future lithium-ion batteries (LIBs). Despite some salient advantages, like low cost, ease of fabrication, high capacity, and higher operating voltage, these materials suffer from low cyclic stability and poor capacity retention. Several different techniques have been proposed to address the limitations associated with LLOs. Herein, we report the surface modification of Li1.2Ni0.13Mn0.54Co0.13O2 by utilizing cheap and readily available silica (SiO2) to improve its electrochemical performance. Towards this direction, Li1.2Ni0.13Mn0.54Co0.13O2 was synthesized utilizing a sol-gel process and coated with SiO2 (SiO2 = 1.0 wt%, 1.5 wt%, and 2.0 wt%) employing dry ball milling technique. XRD, SEM, TEM, elemental mapping and XPS characterization techniques confirm the formation of phase pure materials and presence of SiO2 coating layer on the surface of Li1.2Ni0.13Mn0.54Co0.13O2 particles. The electrochemical measurements indicate that the SiO2-coated Li1.2Ni0.13Mn0.54Co0.13O2 materials show improved electrochemical performance in terms of capacity retention and cyclability when compared to the uncoated material. This improvement in electrochemical performance can be related to the prevention of electrolyte decomposition when in direct contact with the surface of charged Li1.2Ni0.13Mn0.54Co0.13O2 cathode material. The SiO2 coating thus prevents the unwanted side reactions between cathode material and the electrolyte. 1.0 wt% SiO2-coated Li1.2Ni0.13Mn0.54Co0.13O2shows the best electrochemical performance in terms of rate capability and capacity retention.This publication was made possible by NPRP Grant # NPRP11S-1225-170128 from Qatar National Research Fund (a member of the Qatar Foundation). Statements made herein are solely the responsibility of the authors. FE-SEM analysis was accomplished at the Central Laboratory Unit (CLU), Qatar University, Doha, Qatar, TEM analysis was conducted at the Core Labs., QEERI, HBKU, Qatar and XPS analysis was accomplished at the Gas Processing Center (GPC), Qatar University, Doha, Qatar.Scopu

Synthesis, molecular docking with COX 1& II enzyme, ADMET screening and in vivo anti-inflammatory activity of oxadiazole, thiadiazole and triazole analogs of felbinac

Based on the core structure of Felbinac drug, three series (4a–d, 5a–d and 6a–n) of five membered heterocyclic derivatives containing three heteroatoms were designed and synthesized starting from Felbinac. In the rational design of the target molecules, the biphenyl ring along with the methylene bridge of felbinac was retained while the carboxyl group was substituted with biologically active substituents like 1,2,4-triazole, 1,3,4-thiadiazole and 1,3,4-oxadiazole, with an intent to obtain novel, better and safer anti-inflammatory agents with improved efficacy. The prepared molecules were then investigated for their anti-inflammatory, ulcerogenicity and analgesic activity in experimental animals. The tested compounds exhibited varying degrees of inflammatory activity (25.21–72.87%), analgesic activity (27.50–65.24%) and severity index on gastric mucosa in the range of 0.20–0.80 in comparison to positive control felbinac (62.44%, 68.70% and 1.5, respectively). Among all the prepared compounds, 2-(biphenyl-4-ylmethyl)-5-(4-chlorophenyl)-1,3,4-oxadiazole (6c) emerged as the most potent NSAID compound exhibiting the highest anti-inflammatory activity (72.87% inhibition) and analgesic activity (65.24%) along with the least severity index on gastric mucosa (0.20). Further, molecular docking on cyclooxygenase and in silico ADME-Toxicity prediction studies also supported the experimental biological results and indicated that 6c has a potential to serve as a drug candidate or lead compound for developing novel anti-inflammatory and analgesic therapeutic agent(s) with minimum toxicity on gastric mucosa. Keywords: Felbinac, Oxadiazole, Triazole, Thiadiazole, Anti-inflammatory, Molecular dockin

Improved electrochemical performance of SiO2-coated Li-rich layered oxides-Li1.2Ni0.13Mn0.54Co0.13O2

Lithium-rich layered oxides (LLOs) such as Li1.2Ni0.13Mn0.54Co0.13O2 are suitable cathode materials for future lithium-ion batteries (LIBs). Despite some salient advantages, like low cost, ease of fabrication, high capacity, and higher operating voltage, these materials suffer from low cyclic stability and poor capacity retention. Several different techniques have been proposed to address the limitations associated with LLOs. Herein, we report the surface modification of Li1.2Ni0.13Mn0.54Co0.13O2 by utilizing cheap and readily available silica (SiO2) to improve its electrochemical performance. Towards this direction, Li1.2Ni0.13Mn0.54Co0.13O2 was synthesized utilizing a sol–gel process and coated with SiO2 (SiO2 = 1.0 wt%, 1.5 wt%, and 2.0 wt%) employing dry ball milling technique. XRD, SEM, TEM, elemental mapping and XPS characterization techniques confirm the formation of phase pure materials and presence of SiO2 coating layer on the surface of Li1.2Ni0.13Mn0.54Co0.13O2 particles. The electrochemical measurements indicate that the SiO2-coated Li1.2Ni0.13Mn0.54Co0.13O2 materials show improved electrochemical performance in terms of capacity retention and cyclability when compared to the uncoated material. This improvement in electrochemical performance can be related to the prevention of electrolyte decomposition when in direct contact with the surface of charged Li1.2Ni0.13Mn0.54Co0.13O2 cathode material. The SiO2 coating thus prevents the unwanted side reactions between cathode material and the electrolyte. 1.0 wt% SiO2-coated Li1.2Ni0.13Mn0.54Co0.13O2shows the best electrochemical performance in terms of rate capability and capacity retention.Other Information Published in: Journal of Materials Science: Materials in Electronics License: https://creativecommons.org/licenses/by/4.0See article on publisher's website: http://dx.doi.org/10.1007/s10854-020-04481-6</p