Li-Storage Performances of Copper l-Phenylalanine Complex Nanosheets Anode Derived from Waste Copper Etchant

Abstract Abstract In this work, copper l -phenylalanine (abbreviated as Cu(L-Phe) 2 ) complex was extracted from the waste acid Cu-printed-circuit-board (Cu-PCB) etchant via a one-step facile liquid phase precipitate reaction for the first time. The corresponding application feasibility in lithium-ion battery (LIB) and the electrochemical Li-storage mechanism were also explored. The resultant Cu(L-Phe) 2 complex displayed a nanosheet-like morphology with 200 nm in thickness. When it was used as the anode active material of LIB, the reversible discharge specific capacities were 231.1 mAh/g at 100 mA/g and 47.2 mAh/g at 5 A/g, respectively. Furthermore, with the help of surfactant sodium dodecyl sulfate (SDS), Cu(L-Phe) 2 complex nanosheets rearranged into the orderly flower-like cluster with a diameter of 13 μm; correspondingly, the reversible discharge specific capacities also increased to about 278.8 mAh/g and 108.8 mAh/g, respectively, implying higher reversibility and cycle performance. Seemingly, orderly flower-like nanosheets clusters with the hierarchical structure may facilitate to modify the electrochemical Li-storage capacity of Cu(L-Phe) 2 complex anode. Clearly, the satisfactory results may open a new path to develop the circular economy mode of acid waste Cu-PCB etchant, which is very important for environmental protection and sustainable development. Graphic Abstract