Green Synthesis of Co(0) and CoB Nanoparticles from Bean Shell Extract and Determination of the Effect of Their Activity on Sodium Borohydride Hydrolysis

Abstract

Abstract The study investigated the effect of Co(0) and Co-B NPs catalysts synthesized using the method of green synthesis on the NaBH4 hydrolysis process. The investigation of the structure and surface morphology of the catalysts was evaluated using XRD, SEM-EDX, TEM, FTIR, and XPS analyses. The effect of catalysts on NaBH4 was examined at different catalyst amounts, different NaBH4/NaOH concentrations, and different temperature values. At 30°C solution temperature, the highest HGR and TOF values for Co(0) NPs catalyst were determined as 7326 mL.min− 1.g− 1cat and 8572 mL.min− 1.g− 1cat, respectively. Under the same conditions, HGR and TOF values for Co-B NPs catalyst were determined as 12524 mL.min− 1.g− 1cat and 15189 mL.min− 1.g− 1cat, respectively. The calculated activation energies for Co(0) and Co-B NPs catalysts are 37.68 kJmol− 1 and 21.28 kJmol− 1, respectively. Enthalpy and entropy values were calculated as 4.43 kJmol− 1 and 44 Jmol− 1K− 1 for Co(0) and 23.16 kJmol− 1 and 98 Jmol− 1K− 1 for Co-B NPs, using Eyring's equation, respectively. The catalysts showed a small decrease in activity over five cycles, indicating that they have potential for reusability.