Enhancing Photocatalyst Efficiency by Constructing a Flake-like Janus Structure for Efficient Degradation of Benzotriazole

The significance of photocatalysts in scientific research cannot be contested. Enhancing the photocatalytic efficiency is contingent upon catalyst structure design and synthesis strategies that enhance the separation and migration of photogenerated charge carriers. In this study, we utilized the paraffin–water interface as a protective shield for TiO₂ and employed in situ photopolymerization to prepare composite photocatalysts with a distinctive “Flake-like Janus” (FLJanus) structure. The FLJanus structured is composed of a layer of nanosized TiO₂ and a layer of conjugated polymer. We conducted a series of comparisons between the FLJanus structured photocatalyst and a randomly structured photocatalyst prepared under the same conditions. The FLJanus structured photocatalysts exhibit a 126% enhancement in the degradation efficiency of benzotriazole (BTA) compared to the randomly structured photocatalyst. Under simulated sunlight, the best photocatalyst we tested achieved a 90% degradation of BTA within 1 h. The photocurrent results showed that the FLJanus structured photocatalyst exhibited a two-fold increase in photocurrent, while the fluorescence spectra (photoluminescence) indicated a lower fluorescence emission peak, suggesting an enhanced efficiency in photogenerated charge carrier separation. By electron paramagnetic resonance tests and the analyzing of band structure, the electron-transfer mechanism of the Janus composite catalyst was determined in greater detail, indicating that the FLJanus structure had a decisive impact on the spatial charge separation ability of photocatalyst particles. This research shows an inexpensive and scalable preparation method for improving the efficiency of photocatalysts.