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. [Display omitted] • Nitrogen and phosphorus doped starch carbon (NPSC) promoted electron transfer. • Optimal dosage of starch-derived carbon (SC) and NPSC were 400 and 600 mg/L. • NPSC enriched Clostridium butyricum more efficient than SC and control groups. • Metabolism analysis revealed NPSC raised the microbial activity in H 2 evolution. • The highest H 2 yields of SC and NPSC groups were 219.5 and 261.2 mL/g glucose. [ABSTRACT FROM AUTHOR]