Formulation and optimization of Ni-MOF/CuSe nanocomposite ink for high-performance flexible microsupercapacitor

The growth of flexible and wearable electronics drives progress in printed, flexible micro-supercapacitors for energy storage. This study fabricates flexible and foldable micro-supercapacitors using a nanocomposite of Ni-based Metal-Organic Framework (Ni-MOF) and copper selenide (CuSe). The conductive ink, blending Ni-MOF and CuSe, ensures thorough mixing for screen-printing. The resulting devices exhibit impressive electrochemical performance, with the NC-5 FAS device showing high areal capacitance, promising energy density and (3.65 mWhcm −2 and power density (73.8 mWcm −2 ). Integration into a 3D enclosure configuration enhances performance, with improved capacitance, energy density (47.08 mWhcm −2 ) and power density and outstanding power density (985.8 mWcm −2 ), maintaining capacitance retention of the 93.9 % and with highly robust mechanical durability during flexibility tests. This study highlights tailored nanocomposite's potential to revolutionize flexible and foldable energy storage, advancing high-performance, portable electronics. • Printed NC-5 FAS exhibits superior performance with 47.08 mWh cm −2 energy density and 985.8 mW cm −2 power density. • The formulated Ni-MOF/CuSe ink, with 5306 mPa·s viscosity, enables efficient fabrication of flexible supercapacitors. • The 3D FlexiPower Bank enhances the microsupercapacitor discharge time and energy storage by fourfold. • The versatile microsupercapacitors maintain 93.9% capacitance retention and strong durability at various bending angles.