Extraction of Novel Effective Nanocomposite Photocatalyst from Corn Stalk for Water Photo Splitting under Visible Light Radiation

Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets could be successfully prepared from corn stalk pith using a simple alkaline hydrothermal treatment process followed by calcination in an inert atmosphere. The produced nanocomposite was characterized by SEM, EDX, TEM, FTIR, and XRD analytical techniques, which confirm the formation of multilayer graphene sheets decorated by inorganic nanoparticles. The nanocomposite shows efficient activity as a photocatalyst for water-splitting reactions under visible light. The influence of preparation parameter variations, including the alkaline solution concentration, hydrothermal temperature, reaction time, and calcination temperature, on the hydrogen evolution rate was investigated by preparing many samples at different conditions. The experimental work indicated that treatment of the corn stalk pith hydrothermally by 1.0 M KOH solution at 170 degrees C for 3 h and calcinating the obtained solid at 600 degrees C results in the maximum hydrogen production rate. A value of 43.35 mmol H-2/gcat.min has been obtained associated with the energy-to-hydrogen conversion efficiency of 9%. Overall, this study opens a new avenue for extracting valuable nanocatalysts from biomass wastes to be exploited in hot applications such as hydrogen generation from water photo-splitting under visible light radiation.

Automated summary

Novel (Ca, Mg)CO3&SiO2 NPs-decorated multilayer graphene sheets were successfully prepared from corn stalk pith using a simple alkaline hydrothermal treatment process followed by calcination in an inert atmosphere. The nanocomposite exhibited efficient activity as a photocatalyst for water-splitting reactions under visible light. The study investigated the influence of preparation parameters on the hydrogen evolution rate and found the optimal condition to achieve the maximum hydrogen production rate of 43.35 mmol H-2/gcat.min and an energy-to-hydrogen conversion efficiency of 9%.