With an improved charge separation efficiency, the heterojunction catalysts are widely used to enhance photocatalytic activity. However, the transfer mechanism of photoexcited charge carriers remains unclear and the researches about products toxicity are limited. In this work, we reported type-I heterojunctions, Bi2O2CO3/Bi8(CrO4)O11 with varying mass ratios, and their applications on water purification for the first time, and explored the machanism of charge transfer. The 20% Bi2O2CO3/Bi8(CrO4)O11 heterojunction showed the highest photocatalytic activities for the degradation of typical dyes and anticiotics, including bisphenol-A (BPA), methylene blue (MB), rhodamine B (RhB), methyl orange (MO) and tetracycline (TC). The BPA photodegradation rate was 2.37 and 8.83 times higher than those of Bi8(CrO4)O11 and Bi2O2CO3, respectively. The results demonstrated that the internal electric field between Bi2O2CO3 and Bi8(CrO4)O11 could significantly boost the photocatalytic efficiency through highly promoted separation of electron-hole pairs by forming the S-scheme heterojunction. The trapping experiments and electron paramagnetic resonance (EPR) results indicated that hydroxyl radicals, holes and superoxide radicals all act as active species in the Bi2O2CO3/Bi8(CrO4)O11 heterojunction, efficiently extending the practical application of photocatalysts. The possible photodegradation pathways of MB and BPA were proposed based on the results of liquid chromatography-mass spectrometry (LC-MS). Furthermore, we verified that BPA solutions treated by Bi2O2CO3/Bi8(CrO4)O11 heterojunctions are harmless for wheat seed germination. 2D/1D Bi2O2CO3/Bi8(CrO4)O11 photocatalysts displayed great potentials as an environmentally-friendly strategy for wastewater purification.

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