Copper ferrite synthesis from spent Li-ion batteries for multifunctional application as catalyst in photo Fenton process and as electrochemical pseudocapacitor

In this study, from copper recycled from spent lithium-ion batteries (LiBs) is made the synthesis of cupper ferrite (CuFe2O4-LiB). X-ray diffraction, energy dispersive X-ray spectroscopy and inductively coupled plasma optical emission spectrometry (ICP OES) identified the structure and composition of CuFe2O4-LiB. Scanning electron microscopy and transmission electron microscopy showed agglomerates of nanometric spherical particles. This study investigated the multifunctionality of CuFe2O4-LiB. Photocatalytic properties were analyzed by monitoring the decolorization of methylene blue (MB) in a heterogeneous photo-Fenton process in the presence of solar radiation. Decolorization efficiency was 96.1% in 45 min of reaction. Ion chromatography detected formic and acetic acids as products of MB degradation, and by ICP OES measured lower concentrations of 0.09 mgL(-1) and 0.37 mgL(-1), respectively for iron and copper ions in the treated solution. CuFe2O4-LiB electrodes showed great reversibility, charge efficiency, and a specific capacitance of 2.4 Fg(-1) (10.0 mVs(-1)), which are favorable characteristics for pseudocapacitors.