Photothermal Catalytic Degradation of Bisphenol A by CoPc/BiO_2–<i>x</i> Composites under Infrared Light Irradiation: Synergetic Effect of Light and Temperature

Recently, the photothermal synergistic effect, as an emerging concept, has gradually gained the attention of researchers. However, developing an efficient photothermal synergistic catalyst for the degradation of organic pollutants in water is a formidable challenge. In this paper, a novel cobalt phthalocyanine (CoPc)/BiO_2–<i>x</i> photothermal catalyst is designed. Under near-infrared light (NIR) irradiation, the photogenerated electron–hole pairs generated inside BiO_2–<i>x</i> can migrate to the surface of the material and be captured by the abundant oxygen vacancies on the surface of BiO_2–<i>x</i>, enhancing the catalytic activity of BiO_2–<i>x</i>. Meanwhile, the introduction of CoPc broadens the absorption range of light and induces the photothermal effect. It can lead to an increase in the local surface temperature and the gradual release of the lattice oxygen within BiO_2–<i>x</i>, which is converted into reactive oxygen, especially •O₂^–, to further promote the degradation of Bisphenol A (BPA) pollutants in water. As a result, the prepared CoPc/BiO_2–<i>x</i> photothermal catalysts exhibit a better BPA removal efficiency (about 80%), as compared to that of the pristine BiO_2–<i>x</i>. This work provides a new idea for constructing an efficient photothermal catalytic system base on the synergetic effect of light and temperature, which can be used for the photothermal catalytic treatment of aqueous organic phenolic pollutants.