Construction of nitrogen-doped graphene/BiOCl Schottky heterojunction for efficient photocatalytic degradation and CO reduction.

The advancement of an efficient photocatalyst via a straightforward process is critical for environmental remediation and energy conversion. In this study, a series of multifunctional nitrogen-doped graphene/BiOCl (NGBOC) Schottky heterojunction photocatalysts were successfully prepared by hydrothermal method. The systematic characterization and analysis results showed that the addition of NG guided the formation and growth of BiOCl to thinner and smaller nanosheets, during which, under the strong interaction between both, more abundant oxygen vacancies were introduced into BiOCl and a small amount of N element was doped in lattices, ultimately BiOCl and NG with excellent electron transport form Schottky heterojunction. This series of favorable effects not only improve the adsorption capacity of BiOCl to pollutants, but also accelerate the separation and migration rate of photogenerated carriers. Under visible light, the 3NGBOC with optimal content of NG exhibits the highest photocatalytic activity for the degradation of Rhodamine B (RhB) and tetracycline (TC), which is more than four times higher than that of the reference BiOCl. Meanwhile, The NGBOC photocatalysts is highly reusable and has the potential to be recycled five times. Besides, under simulated sunlight, the conversion rate of CO to CO over 3NGBOC was about twice that of a single BiOCl. In addition, capture experiments and room temperature electron paramagnetic resonance (EPR) strongly support the dominant role of hydroxyl radicals and superoxide radicals in photocatalytic reactions. This study reveals the design and preparation of multifunctional BiOCl-based Schottky heterojunction photocatalyst, provides a green economic strategy and promising scheme for promoting environmental remediation and energy conversion.