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Abstract: The mechanical properties of graphene may be strongly affected by defects. In our work, the effects of the orientation and tilting angles of Stone–Thrower–Wales (STW, 5-7-7-5) defects on the mechanical properties of graphene have been investigated based on molecular dynamics simulations. When there is one centred STW defect including STW-1 defect and STW-2 defect, our study reveals that the orientation with respect to the chirality governs the mechanical properties of graphene. For STW-1 defective graphene, the strength of the armchair direction is much lower than that of zigzag direction. While the circumstance for STW-2 defective graphene is opposite, the strength of the armchair direction is much higher than the strength of the zigzag direction. Furthermore, when there is more than one STW defect, the mechanical properties of graphene depends on the tilting angle of STW defects. The breaking strength of graphene decreases with the increasing tilting angle. Our present work could provide significant insights into the effect of STW defects on the mechanical properties of graphene. [Copyright &y& Elsevier]

The failure phenomena of the full cell battery based on Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3 ceramic electrolytes generally manifests as the macroscopic fading of the capacity, the governing mechanisms in the particular term of electrolytes remain elusive. In this study, Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3 electrolytes after cycling are characterized by multiscale techniques, including Scanning Probe Microscopy, to systematically investigate the chemical and structural evolution processes. Secondary phases are proven to exist in the cycled Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3. It is demonstrated that the Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3 electrolytes suffer from both electrochemical and mechanical deterioration during the cycling processes. The changes in both chemical compositional and inhomogeneous mechanical stress result in the failure of the electrolyte and pose high resistance to lithium-ion transport. Furthermore, the ionic transport process is successfully manipulated by a local electric field with amplitude of 2 V and 4 V from the tiny tip in Scanning Probe Microscopy. Based on the observed electrochemical strain response and contact stiffness variation induced by dynamic Li-ion fluctuation under an applied AC electrical field, the degradation process of the Li 1.5 Al 0.5 Ge 1.5 (PO 4) 3 electrolyte is studied. It is determined that the chemo-mechanical degradation originates from the non-uniform Li ion distribution at the boundaries and/or voids in the interior of the electrolyte. • LAGP solid electrolytes after cycling are characterized by various techniques. • Secondary phases are proven to exist in the cycled LAGP solid electrolyte. • LAGP suffer from both electrochemical and mechanical deterioration after cycling. • Ionic transport process is successfully manipulated using SPM techniques. [ABSTRACT FROM AUTHOR]