Phosphorus and oxygen doped carbon-based on Spirulina microalgae as efficient metal-free catalysts to obtain H2 from methanolysis of NaBH4

Metal-free catalysts (SP-KOH-P) doped phosphorus and oxygen as a result of modification with H3PO4 to the surface of the activated carbon sample (SP-KOH) obtained by activation of KOH with Spirulina microalgae were used to obtain hydrogen (H-2) from methanolysis of NaBH4. The characteristic structure of SP-KOH-P and SP-KOH metal-free catalysts were examined by XRD, TEM, elemental analysis, FTIR, and ICP-MS. The effects of the amount of catalyst, NaBH4 concentration, reusability, and temperature on H-2 production rate from NaBH4 methanolysis reaction were investigated. The hydrogen production rate (HGR) obtained with 25 mg SP-KOH-P was found to be 19,500 mL min(-1) g(-1). The activation energy (Ea) value of SP-KOH-P metal-free catalyst sample was calculated as 38.79 kJ mol(-1). (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.