fig1

Figure 1. (A) Comparison of conventional pretreatment routes with low-temperature plasma-assisted purification for the removal of carbon and PVDF residues from spent cathode materials; (B) Schematic illustration of rock-salt phase reconstruction and Li/Ni disorder recovery associated with Ni oxidation; (C) Heating protocol of in situ variable-temperature XRD and temporal evolution of Li/Ni cation disorder and a- and c-axis lattice parameters of NMC811 during heat treatment. The Li/Ni cation-mixing fraction and lattice parameters were obtained from Rietveld refinement of the XRD patterns. This figure is reprinted with permission from Ref.^[6]. Copyright © 2026 Elsevier. PVDF: polyvinylidene fluoride; XRD: X-ray diffraction.