Low-cost cement-polypyrrole composite electrodes for next-generation high performance supercapacitors

Supercapacitors (SCs) have emerged as highly promising energy-storage devices for managing intermittent power supplies. In this study, cement as an abundant building material is explored as an active electrode component and reinforced with polypyrrole (PPy) to enhance conductivity and electrochemical performance. A comprehensive material characterization, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDX), is employed to elucidate the structural and chemical properties of the cement/PPy composites. Electrochemical measurements demonstrate the favorable performance of the fabricated SCs. In a two-electrode system using activated charcoal as the negative electrode, the hybrid SC device exhibits a specific capacitance of 44.95 F g−1 with corresponding energy and power densities of 6.245 Wh kg−1 and 198.12 W kg−1, respectively. Additionally, cement/PPy composites deposited on nickel foam exhibited enhanced electrochemical performance, reaching a maximum areal capacitance of 62.7 mF cm−2. These findings successfully demonstrate the potential of cement-based composites as viable electrode materials for SCs, providing an excellent and sustainable alternative for large-scale energy-storage applications.