Fig. 4: Mechanism of improved metal recovery in galvanic leaching system.
From: Galvanic leaching recycling of spent lithium-ion batteries via low entropy-increasing strategy
XRD pattern of a raw materials and b 40 min leaching products. The local magnification of c 003 peak and d 2θ = 43–66° at different leaching times. e Ni 2p XPS spectra of 5 min leaching products by in-depth etching and f the corresponding Ni atomic percent from the surface to the bulk. g Ni 2p XPS spectra inside raw materials and 10 min leaching products, measured after 1200 s surface etching, respectively. h The atomic percent of Ni inside different leaching products, measured after 1200 s surface etching. i Ni K-edge XANES. j The first derivative of XANES. k Ni K-edge extended X-ray absorption fine structure spectra. l–n The 2D contour Fourier-transformed Ni K-edge EXAFS analysis. All leaching products were obtained from galvanic leaching system with the optimal leaching parameters.
