Cobalt boosts copper sulfide battery performance in energy storage test
Researchers improved the electrochemical properties of copper sulfide by substituting cobalt into its crystal structure, according to a new study in the Journal of Energy Storage. The finding could help manufacturers develop cheaper, longer-lasting batteries for grid storage and electric vehicles—a critical bottleneck for renewable energy adoption.
Originaltitel: Enhancing the electrochemical properties of CuS through cobalt substitution: Experimental and density functional theory insights
<p>In this work, various amounts of Co were substituted into CuS via a hydrothermal method to improve the supercapacitor and electrocatalytic performance. X-ray diffraction analysis demonstrated the phase purity and structural integrity of the Cu<sub>1-x</sub>Co<sub>x</sub>S material, with slight peak shifts, confirming the effective incorporation of cobalt. By substituting the Co<sup>2+</sup> element, the platelike CuS morphology transformed into a particular one. The Cu<sub>0</sub>.<sub>95</sub>Co<sub>0.05</sub>S material exhibited a higher specific capacitance of 1085 F g<sup>−1</sup> at 1 A g<sup>−1</sup> and retained 589.5 F g<sup>−1</sup> at 20 A g<sup>−1</sup>. The Cu<sub>0</sub>.<sub>95</sub>Co<sub>0.05</sub>S//activated carbon (AC) capacitor stored electrical energy with an energy density of 39.4 Wh kg<sup>−1</sup> and a capacity retention of 76.4% at 5 A g<sup>−1</sup> over 3000 cycles. Furthermore, the Cu<sub>0</sub>.<sub>95</sub>Co<sub>0.05</sub>S material exhibited higher electrocatalytic activity, with small overpotentials of 129.1 and 127.8 mV for the hydrogen (HER) and oxygen evolution reaction (OER), respectively, at a current density of 10 mA cm<sup>−2</sup>. The experimental results were confirmed by density functional theory (DFT) calculations of the density of state, quantum capacitance, and adsorption energy of various intermediates.</p>