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• Amorphisation and recrystallisation technique was employed for simulated synthesis. • Composite nanosheets (2D) and nanoporous (3D) materials were generated. • XRDs and microstructures showed presence of layered-spinel intergrowths. • Bulk and nanoporous LiMn 2 O 4 can withstand stresses associated with cycling. Mechanical stresses originate from various factors, such as mechanical load, operational vibration, diffusion during cycling, and thermal expansion coefficients. Li-ion intercalation causes lattice expansion that will impart stress on neighbouring regions and ion mechanical degradation within the layers, which leads to weaker battery performance and eventual failure. The current study reports on the advances in the simulated synthesis of nanosheet, nanoporous, and bulk ternary LiMn 2 O 4 spinel from an atomic perspective, during which amorphisation and recrystallisation techniques were employed and the microstructures reflect the spinel and layered heterostructures. Analysis of mechanical and structural properties is carried out via stress-strain, x-ray diffraction (XRD), radial distribution functions (RDF) graphs, and molecular graphics systems before and after subjection to strain. Subsequently, molecular graphics for the nanoporous material indicated a rigid tunnel framework, whilst the bulk framework showed tilting upon compression. These structural deformations within the bulk might prevent efficient Li transport into/out of the electrode materials. [ABSTRACT FROM AUTHOR]

Nano-architectured Li x TiO 2 are promising as anode electrode materials for lithium rechargeable batteries due to their ability to accommodate and transport lithium atoms at low and elevated temperatures. In the current study, lithiated nanosheets with concentrations, Li 0. 03 TiO 2 and Li 0. 07 TiO 2 , were crystallised from amorphous precursors at 2000K, using large scale molecular dynamics (MD) simulation method, which was followed by a cooling process towards 0 K. The cooled nanosheets, Li 0. 03 TiO 2 and Li 0. 07 TiO 2 , were subsequently heated at temperature intervals of 100 K from 100 K to 500 K with a Nose-Hoover thermostat. The calculated Ti-O radial distribution functions (RDFs), were used to confirm the extent of crystallisation after cooling. The simulated X-ray diffraction (XRD) spectra, at low (0 K) and high (500 K) temperatures, exhibit peaks associated with both rutile and brookite polymorphs. Microstructural features also depicted diffusion pathways with rutile and brookite character, consistent with XRD results. These results confirm that the Li 0. 03 TiO 2 and Li 0. 07 TiO 2 nanosheets are good candidates for anode materials in lithium ion batteries (LIB), since they can contain and transport lithium ions well, even under higher temperature conditions. Lithiated snapshots of evolving microstructures of nanosheets (Li 0. 03 TiO 2) at 0 K and 500 K with different types of defects. Image 1 • We report first time atomistic simulation of TiO 2 nanosheets materials intercalated with 0.03 and 0.07 Li ions. • The L 0.03 TiO 2 and L 0.07 TiO 2 nanosheets shows wide open channels after recrystallisation synthesis. • The crystalline L 0.03 TiO 2 and L 0.07 TiO 2 nanosheets show closed channels after cooling process. • The materials shows similar characteristics at low and high temperature which are then excellent anode electrode materials. [ABSTRACT FROM AUTHOR]