The Role of Cu₂O Mesoporous Spheres in the Removal of Organic Pollutants: Photocatalyst or Adsorbent?

Cuprous oxide (Cu2O) is a kind of functional and promising energy material, which has been used as solar cells, adsorbents, and lithium ion battery electrode materials. And its mainly application is toward photocatalytic reactivity of organics' decomposition under visible light irradiation. However, the real role of Cu2O remains debated, for these reports don't give a powerful evidence to prove its significant photocatalytic properties. Here, we describe a one-pot synthesis method to construct Cu2O mesoporous spheres with large specific surface area at room temperature. This mesoporous microstructure is controlled through an Ostwald ripening-based dissolved partly process. And Cu2O mesoporous spheres are used to study the property of removing organic pollutants. We distinguish the real role of Cu2O by carefully measure the reduced portion of photocatalyst or adsorbent, while it is reacting with organic pollutants. At last, we find out the reason that has caused the concentration of organic pollutants to decrease is mainly based on the adsorption property of Cu2O, rather than its photocatalytic effect. However, the photocatalytic effect of Cu2O is very low under visible light irradiation.