Synthesis of pH-controlled nanoparticles of CuO@CuFe2O4 as anode material for advanced lithium ion batteries

This work described a facile synthesis of combining two-component nanoparticle of CuO and CuFe₂O₄ (CFO) at three different pH values of 9, 10, and 11, followed by heat treatment at 750 °C for 3 h (denoted as CFO_9, CFO_10, CFO_11, respectively). X-ray diffraction and scanning electron microscope were used to analyze the morphological characteristics of the as-prepared samples. The results exhibited that CFO particle size decreased contrary to pH from 9 to 11. These three anode materials reached high initial capacities of over 1100 mAh g⁻¹, and the capacities excellently remained over 500 mAh g⁻¹ through 100 cycles at the current rate of 100 mA g⁻¹. Moreover, the CFO_10 electrode showed a notably capacity retention with a capacity of 621 mAh g⁻¹ after 100 times of lithiation/delithiation, demonstrating that the CFO_10 composite is a promising material for anode electrodes in lithium-ion batteries.