A research team led by Prof. WU Zhengyan from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences (CAS) has recently introduced a high-efficiency Z-scheme photocatalyst to deal with contaminants in water. This new solution has been published in ACS Applied Nano Materials.

In recent years, rapid industrialisation has caused increasingly severe environmental pollution. Therein, various organic pollutants in water have become major threats for human health and ecosystem security worldwide. Therefore, an effective treatment approach has become an urgent task for elimination of organic pollutants at present. 

In this research, the Bi₂WO₆(CdTeQDs/2DBWO) photocatalyst with a giant built-in electric field (BEF) was proved to extremely promote the dissociation of exciton and generation of reactive oxygen species. The researchers demonstrated that BEF plays a positive role in photocatalytic process, and the photodegradation efficiency of phenol, rhodamine B and tetracycline by BEF is much higher than that of pure Bi₂WO₆ under visible light.  

Compared with the commercial TiO₂ photocatalyst, the self-prepared CdTeQDs/2DBWO photocatalyst has a slight advantage in photocatalytic efficiency for pollutants. However, due to the complicated synthesis process and high cost, there are still some difficulties in the practical application of self-prepared photocatalyst.  

This study opens up a new route for designing high-efficiency photocatalysts.

This research was supported by the National Key R&D Program of China, the Science and Technology Service Program of CAS, the Science and Technology Major Project of Anhui Province and the Key R&D Program of Ningxia Province.

Figure 1. The prepared CdTeQDs/2DBWO photocatalyst with different proportions. (Image by YANG Pengqi) 

Figure 2. Schematic illustration of photocatalytic degradation mechanism. (Image by YANG Pengqi)