Oxygen and nitrogen-doped metal-free microalgae carbon nanoparticles for efficient hydrogen production from sodium borohydride in methanol

Here, the oxygen(O) and nitrogen(N) doped metal-free carbon synthesis including potassium hydroxide (KOH) activation of Spirulina Platensis microalgae, followed by nitric acid (HNO3) activation is reported for the first time. Oxygen and nitrogen-doped metal-free catalysts were investigated for efficient hydrogen (H-2) production from methanolysis of sodium borohydride (NaBH4). Compared to the catalyst obtained with the KOH activation, the catalytic activity for O and N doped metal-free showed about a four-fold improvement. The catalysts were analysed by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD), nitrogen adsorption, elemental analysis and Fourier-transform infrared spectroscopy (FTIR). The effects of temperature, NaBH4 amounts, catalyst loading and reusability experiments on the catalytic performance of obtained metal-free catalysts by H-2 release from NaBH4 methanolysis were performed. This study can provide a new alternative strategy to produce specific metal-free carbon catalysts doped heteroatom for environmentally friendly conversion to produce H-2 efficiently. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.