Visible‐Light Response and High‐Efficiency Photocatalytic Elimination of Polycyclic Organic Pollutants of Layer‐By‐Layer Assembled Ternary Nanotubular Catalysts

Recently, visible‐light response and high–efficient photocatalysis for polycyclic organic pollutants of cancer risk has attracted great attention. However, the efficient control and heterojunction fabrication of nanocomposite catalysts for enhanced separation and transfer of interfacial charges remains challenging. Herein, a ternary heterojunction composite photocatalyst (HTTC) was fabricated by utilizing the ultrathin layered titanium dioxide (TiO2) nanostructures, with photocatalytic reactive facets (A101 and R101) prepared from the commercially available TiO2, coating onto outside surface of multi‐walled carbon nanotubes (CNTs) with chemical connection of Ti‐O=C and Ti‐O−C bond, and then the single layer H2TCPP molecules chemically coated onto outside surface of ultrathin layered TiO2 nanostructures with formation of Ti−O‐C=O chemical bond by layer‐by‐layer (LbL) assembly. The interface layer synergistic effects greatly enhance photocatalytic efficiency for high concentrations solution of polycyclic organic pollutants (methylene blue (MB), Rhodamine B (RhB) and oxytetracycline (OTC) under visible light irradiation, and the photodegradation rates of the photocatalysts for MB (and RhB) were 61 times (and 8 times) higher than that of pure P25. The joint interfacial fabrication strategy and composite engineering affords us a facile guideline for the nanocomposite photocatalysts for environmental protection and ecological conservation. A ternary heterojunction composite photocatalyst was successfully fabricated by simple and high‐effective approach for environment. H2TCPP, serves as light‐harvesting agent. Meanwhile, CNTs can improve the photocatalytic efficiency, serves as electron conductor and absorbent. HTTC composite exhibited better chemical stability because of the formation of Ti‐O−C and Ti−O‐C=O bonds. The unique tube‐tube hybrid structure of the photocatalysts was contributed to induce interfacial charge transfer and enlarge specific surface area. Thus, the new material was of great significance to wastewater purification.