Green synthesis of pistachio shell-derived biochar supported cobalt catalysts and their catalytic performance in sodium borohydride hydrolysis

Abstract

Pistachio shell-derived biochar supported cobalt catalysts were synthesized by using a modified impregnation-chemical reduction method. Polydopamine (PDA) and tannic acid (TA) were used as reducing and functionalizing agents. The effect of modification treatment was investigated on the physicochemical and catalytic properties. The peaks observed in XRD patterns belonged to biochar and cobalt. The surface area, total pore volume and pore diameter values of Co-PDA@BC catalyst were determined as 268 m2/g, 0.262 cm3/g and 3.03 nm, respectively. These values higher than that of Co-TA@BC catalyst. FTIR spectra exhibited bands representing the biochar structure. XPS spectra showed that cobalt was embedded in the support structure in metallic and oxide form. The use of PDA improved structural properties and catalytic activity of catalyst. The maximum hydrogen generation rate and activation energy for Co-PDA@BC was determined as 25 mL min−1gcat−1 and 31.3 kJ mol−1, respectively.