Constructing Z-scheme Nd:Bi2WO6/CdS nanostructures for efficient degradation of organic pollutants: Structural, optical and photocatalytic properties, and mechanistic insights

Bismuth tungstate-based semiconductor materials exhibit unique environmental purification and energy conversion capabilities, becoming a hotspot to address the environmental pollution and energy shortage. However, the high recombination rate of carriers and dissatisfactory photocatalytic degradation efficiency limit their practical application. Here, different pH conditions of precursor solution were used to synthesize Nd:Bi2WO6 nanostructures with in situ CdS epitaxial layer (NBWO/CS) and their structure, optical properties and photocatalytic performance were studied in detail. Under the optimized pH = 6, the resulting NBWO/CS exhibits the best performance at 58.7% for RhB within 2 h, which is ascribed to the excellent separation of photogenerated electron-hole pairs. In addition, the mechanisms of photocatalytic degradation for organic contaminants as well as generation and separation of carriers were further exposed. This work provides theoretical foundations and technical support for the development of high-performance photocatalytic materials to decontaminate the environment and convert energy.