Solar Reforming Lignocellulose into H2 over pH-Triggered Hydroxyl-Functionalized Chalcogenide Nanotwins

H-2 production by lignocellulose photoreforming is deemed to be a promising approach for the conversion of solar energy to fuels yet in limited efficiency to date. Herein, we bring a record-breaking H-2 evolution activity with a large amount of observable H-2 bubbles generated in the basic alpha-cellulose photoreforming reaction using a nanotwinned CdZnS photocatalyst (CZS). Subsequently, an outdoor compound parabolic concentrator-based reactor is developed to scale up this system to 7.2 m(2) and a H-2 production rate of 615 mL h(-1) under direct solar irradiation was obtained. We demonstrated the vital function of the basic solution pH in accelerating the oxidation semireaction kinetics. The pH dependence of the hydroxylated surface over CZS nanotwins features efficient hole transfer and rapid hydroxyl radical generation by inducing favorable reaction kinetics/thermodynamics in alkaline solution, enabling highly effective photoreforming activity. This work provides a state-of-art example of efficient H-2 production via lignocellulose photoreforming.

Automated summary

This study presents an efficient method for hydrogen production through lignocellulose photoreforming, using a nanotwinned CdZnS photocatalyst in alkaline solution with observable hydrogen bubble generation. A reactor based on a compound parabolic concentrator was developed to achieve high hydrogen production under direct solar irradiation.