Boosting the capacitive property of binary metal tellurium of MnCoTe/NiFeTe yarn coils-like through surface engineering for high-performance supercapacitors

Improving the performance of electrode materials based on transition metals can significantly push advancements in energy storage devices. In this work, we offer a novel in situ tellurization approach to synthesize brand-new decorated yarn-coils MnCoTe/NiFeTe on a NiF (labeled MCTe/NFTe@NiF) which makes them attractive candidates for electrode materials in hybrid supercapacitors. At first, two consecutive hydrothermal methods were used to create electrode materials MnCo-LDH and MnCo-LDH/NiFe-LDH on nickel foam, respectively. In the following, electrode material MnCo-LDH/NiFe-LDH was subjected to a tellurization process to create MnCoTe/NiFeTe nanostructures. The direct growth strategy of electrode materials on a conductive substrate (NiF) effectively eliminates the need for polymer binder or conductive materials, thereby facilitating the redox process. The MnCoTe/NiFeTe@NiF electrode benefits from the synergistic effects of conductive tellurium and yarn coils-like morphology, resulting in faster electron/ion transport, increased efficiency, and superior electrochemical performance. The MCTe/NFTe@NiF electrode reveals highly desirable electrochemical characteristics, including a specific capacity of 223.36 mA h/g at 1 A/g, and reliable longevity surpassing 10,000 GCD cycles, with maintaining 73.18 % of its initial specific capacity at 30 A/g. We have prepared a hybrid supercapacitor (labeled MCTe/NFTe@NiF(+)//AC@NiF(-)), which utilizes the positive MCTe/NFTe@NiF and the negative AC@NiF electrodes. This hybrid supercapacitor indicated an excellent energy density of 51.55 Wh/kg, a power density of 799.98 W/kg, and showed substantial longevity (92.33 % after 10,000 GCD cycles).