Reducing the recombination rate of photoexcited electron–hole pairs is always a great challenging work for the photocatalytic technique. In response to this issue, herein, a novel Z-scheme CuInS2/In2O3 with interfacial S–O linkages was synthesized by a hydrothermal and subsequently annealing method. The Fourier transform infrared (FT-IR) and X-ray photoelectron spectrometer (XPS) measurements confirmed the formation of covalent S–O bonds between CuInS2 and In2O3. The quenching and electron spin resonance (ESR) tests revealed the Z-scheme transfer route of photogenerated carriers over the CuInS2/In2O3 heterojunctions, which was further verified theoretically via density functional theory (DFT) calculations. As expected, the CuInS2/In2O3 heterojunctions showed significantly boosted photocatalytic activities for lomefloxacin degradation and Cr(VI) reduction under visible light illumination compared with the bare materials. Accordingly, a synergistic photocatalytic mechanism of Z-scheme heterostructures and interfacial S–O bonding was proposed, in which the S–O linkage could act as a specific bridge to modify the Z-scheme manner for accelerating the interfacial charge transmission. Furthermore, the CuInS2/In2O3 heterojunction also exhibited excellent performance perceived in the stability and reusability tests. This work provides a new approach for designing and fabricating novel Z-scheme heterostructures with a high-efficiency charge transfer route.
The rational design of heterostructure photocatalysts is of great significance for maximizing the synergistic effects from individual material characteristics during photocatalytic processes. Herein, a triple-engineered Bi 4 O 5 Br 2 /FeS 2 heterojunction was successfully developed via a combined calcination–hydrothermal method. The optimized heterojunction (BOB/FS-21) demonstrated a cefalexin degradation rate of 98.6 % within 60 min, and exhibited exceptional performance in the treatment of real pharmaceutical wastewater, effectively reducing the COD from 7852 mg/L to 1987 mg/L. The superior performance was attributed to the following benefits, either directly or indirectly: i) interfacial S − O bonds built specific charge transfer channels, ii) Z -scheme mode optimized the charge transfer path, iii) photothermal-assisted effect accelerated reaction kinetics and suppressed carrier recombination. Experiments, characterizations, and calculations collectively validated these synergistic benefits driving the efficient and active charge transfer process, realizing a unified “three-in-one” functional system. Besides, the breakdown mechanism of cefalexin was investigated by employing mass spectrometry and DFT methods, and a toxicity evaluation of the intermediate products during degradation was carried out using toxicological assessments. Overall, this work establishes a triple-synergy paradigm for the design of advanced heterogeneous photocatalysts toward sustainable antibiotic remediation.
危险品化学品经营许可证（带存储）