Carbon-Shielded Selenium-Rich Trimetallic Selenides as Advanced Electrode Material for Durable Li-Ion Batteries and Supercapacitors

In order to achieve a sustainable future, researchers must continue to research improved electrode materials. Considering the high electronic conductivity, versatile redox activity, and enhanced energy storage performance, nanostructures have been employed as a novel electrode material for high-performance lithium-ion batteries (LIBs) and supercapacitors. Herein, carbon-coated selenium-rich trimetallic selenide (Cu₂NiSnSe₄@C) nanoparticles (NPs) as an efficient electrode material in energy storage devices are prepared. The prepared core-shell Cu₂NiSnSe₄@C NPs electrode is employed as an anode material for LIBs, which demonstrated a high reversible specific capacity of 988.46 mA h g⁻¹ over 100 cycles at 0.1 A g⁻¹ with good rate capability. Additionally, the core-shell Cu₂NiSnSe₄@C NPs electrode exhibited an outstanding capacity of 202.5 mA h g⁻¹ at 5 A g⁻¹ even after 10 000 cycles. Exploiting the synergistic characteristics, the core-shell Cu₂NiSnSe₄@C NPs material is also investigated as a battery-type electrode for hybrid supercapacitors. The assembled hybrid supercapacitor with Cu₂NiSnSe₄@C NPs and activated carbon showed excellent rate capability including high power (5597.77 W kg⁻¹) and energy (64.26 Wh kg⁻¹) densities. Considering the simple synthesis and enhanced energy storage properties, carbon-coated selenium-rich trimetallic selenide can be used as a durable electrode material for practical energy storage devices.