<p>This work conducts an experimental comparison of various binary transition metal selenides (BTMSe’s) to discover promising materials for supercapacitor (SCs) electrodes. Researchers are currently investigating the potential of selenide-based materials and their nanostructures in the realm of energy storage devices. Although, there is limited research examining the practicality of employing BTMSe’s as electrode materials. Herein, selenide-based materials such as MnSe, NbSe₂ and their nanocomposite MnSe@NbSe₂ were synthesized via the hydrothermal technique. Supercapacitors (SCs) with exceptional characteristics were observed, notably outstanding cycling stability exceeding 6000th cycle, specific energy (58.72 Wh kg⁻¹), specific power (281 Wh kg⁻¹), and specific capacitance (<i>C</i>_sp) of 2079 F g⁻¹ at 1 A g⁻¹, as indicated by thorough analysis. There is a significant consensus in material synthesis methods and a plethora of new insights into the charge-storage process in emerging capacitive electrodes for future storage devices.</p> Graphical Abstract <p></p>