The structure-activity relationship between precursor fine structure and cathodes performance in Ni-rich layered oxide

Cathode’s primary particle structure plays a key role in the performance of lithium ion batteries, which can be controlled by the precursor synthesis. Regretfully, the relevance between primary particle structure and cathode performance is not explicitly elucidated, that is, what is the discrepancy of cathode’s primary particle size on the structural degradation? In order to elaborate the structure-activity relationship between them, we have systematically investigated the regulation of primary particle size through an in-depth analysis of the precursor growth mechanism, ammonia-stirring coupling and hydrodynamics optimization. Structural and electrochemical characterizations of LiNi0.92Co0.04Mn0.04O2 with different primary sizes (336, 447, 565 and 675 nm) and a rounded analysis of structural degradation after cycling provide insight into the correlation between precursor fine structure and cathode performance, i.e. larger cathode’s primary particle size can effectively inhibit CEI film formation, structure decay, the intragranular/intergranular cracks formation owing to the alleviation of localized stress.

Properties of WCCo Composites Produced by the SPS Method Intended for Cutting Tools for Machining of Wood-Based Materials

This paper presents the possibility of using the Spark Plasma Sintering (SPS) method to obtain WCCo composite materials. Such materials are used as cutting blades for machining wood-based materials. Two series of composites, different in grain size and cobalt content, were analyzed in the paper. The produced materials were characterized using Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and tribological properties were determined. In addition, preliminary tests were carried out on the durability of the blades made of sintered WCCo composites while machining three-layer chipboard. The results of the microstructure analysis proved that the SPS method makes it possible to obtain solid composites. Phase analysis showed the occurrence of the following phases: WC, Co, and Co3W9C4. The lowest friction coefficient value was found in samples sintered using powder with an average primary particle size of 400 nm (ultrafine).

Thiol Adsorption on Metal Oxide Nanoparticles

The adsorption of 2-naphthalenethiol (2-NPT) and methanethiol (MT) on 13 different metal oxide nanoparticles, of approximately 30 nm average primary particle size, has been investigated. In the case of 2-NPT,...