Transition metal-complexed lactone-functionalized poly(benzofuran-co-arylacetic acid) for enhanced supercapacitor efficiency

Energy is a crucial and often debated topic in today’s world. Polymer–metal complexes significantly enhance the electrochemical performance of supercapacitors, providing benefits in conductivity, stability, and charge storage capacity. This study investigates the following transition metals: cobalt, nickel, copper, and zinc, which are used to synthesize organometallic polymers with poly(benzofuran-co-arylacetic acid) to enhance electrochemical performance. The synthesized organometallic polymers were then thoroughly characterized using advanced spectroscopic techniques, including Fourier-transform infrared spectroscopy, photoluminescence, X-ray photoelectron spectroscopy, and electron paramagnetic resonance spectroscopy. The compounds were obtained as amorphous powders with different degrees of crystallinity. X-ray photoelectron spectra confirm that the metals in the structure of the complexes exist mainly in the form of M 2＋ oxidation state. The influence of the type of complexed metal on thermal stability, optical, and electrochemical properties was investigated and compared with that of the organic ligand. The metal complexes were used as electrode materials in all-in-one two-electrode supercapacitor devices, yielding impressive results. The Co-PBAAA-based supercapacitor exhibited a greater contribution from capacitive energy storage than other reported Zn-, Ni-, and Cu-complexes, suggesting that electric double-layer capacitors and surface-confined faradaic reactions play a key role in enhancing the electrochemical properties. The Co-PBAAA-based supercapacitor device exhibits the highest specific capacitance value at each scan rate, indicating superior performance. At 10 mV s −1 , a specific capacitance of 793 F g −1 was achieved, which is very promising for energy storage applications. The energy and power density values measured for the Co-PBAAA-based supercapacitor device are promising, with values of 110.19 Wh kg −1 and 3966.67 W kg −1 , respectively. • Co 2＋ , Ni 2＋ , Cu 2＋ , and Zn 2＋ metal complexes of poly(benzofuran-arylacetic acid. • Incorporating metallic ions positively impacts supercapacitive properties. • The Co-PBAAA-based supercapacitor device exhibits the highest specific capacitance value. • At 10 mV/s, a specific capacitance of 793 F/g was achieved. • The energy and power density values measured are 110.19 Wh/kg and 3966.67 W/kg.