Nitrogen-phosphorus doped starch carbon enhanced biohydrogen production

To solve the thermodynamic limitations on the hydrogen (H-2) yield by dark fermentation (DF), the conductive carbons are usually used to mediate the H-2-DF. In this work, the nitrogen (N)-phosphorus (N) doped starch carbon (NPSC) was prepared and characterized to investigate its influence on H-2-DF. NPSC effectively raise H-2 yield compared with starch-derived carbon (SC). The optimal dosage of SC (400 mg/L) and NPSC (600 mg/L) caused the highest H-2 yield of 219.5 and 261.2 mL/g glucose, respectively, being higher than the control yield (161.4 mL/g glucose). Factually, compared with the control group without any carbon, NPSC optimized the microbial community structure and increased the abundance of C. butyricum from 19.09% to 30.87%. This fact increased the shift of metabolic pathway to butyric acid evolution, thereby promoting the substrate conversion level to H-2. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.