Journal of Applied Electrochemistry, vol.53, no.8, pp.1643-1655, 2023 (SCI-Expanded)
The originality of our current work is based on the use of H3PO4 functionalized waste poplar sawdust as a supercapacitor electrode material and catalyst for NaBH4 methanolysis reaction. N2 adsorption–desorption, scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM–EDX), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) are utilized for characterization of the activated carbon (AC). In the first stage of our study, the effect of H3PO4 ratios and carbonization temperature on the hydrogen generation rate (HGR) is investigated and optimized. The optimum H3PO4 and carbonization temperature for NaBH4 methanolysis on AC are determined as 4:1 and 600 °C, respectively. The optimum points for the methanol concentration, NaBH4 concentration, reaction temperature, and catalyst amount affecting the HGR values for the methanolysis reaction on the KV4-600 catalyst under these conditions are determined as 4 ml, 1.25 wt% NaBH4, 60 °C, and 50 mg, respectively. Moreover, the HGR, activation energy, and the reaction completion duration under optimized reaction conditions are obtained as 19,050.00 mL min−1 gcat−1, 11.76 kJ mol−1, and 60 s, respectively. The performance of the KV4-600 as a supercapacitor electrode material is evaluated by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The specific capacitance of the KV4-600 at a specific current of 0.25 A g−1 is found to be 161.15 F g−1. KV4-600 shows satisfactory results both as supercapacitor electrode material and as catalyst for NaBH4 methanolysis. Graphical Abstract: [Figure not available: see fulltext.]