Fabrication Of NiCoP Nano Photocatalysis For The Photodegradation Of Tetracycline

As an emerging class and ubiquitous occurrence of emerging and ubiquitous refractory organic pollutants,pharmaceutical and personal care products（PPCPs）have been produced and heavily consumed in modern society.The residual concentration of PPCPs in water has increased the risk of environmental pollution.As a widely used antibiotic,tetracycline（TC）has attracted extensive attention due to its large amount of discharge in the environment and its potential harm to the environment.As reported,photocatalysis is one of the most attractive method to degrade TC.Transition metal phosphide（TMPS）has advantages of low toxic,low cost and high natural abundance,which can replace the noble metal co-catalyst to achieve efficient photocatalytic degradation.Among them,NiCoP has a synergistic effect between nickel and cobalt,which can provide more redox reaction sites.Moreover,the presence of NiCoP co-catalyst could enhance the transfer rate of photogenerated charge between the materials,which can improve the photodegradation efficiency significantly.Based on the previous studies and the advantages of NiCoP co-catalyst,the following innovative works were carried out.（1）TiO₂/PPy/NiCoP nano photocatalyst was prepared by sol-gel,in-situ polymerization and one-step chemical reduction method.TiO₂/PPy/NiCoP nanocomposites was characterized by SEM、TEM、XPS、XRD methods.The effects of reaction time,initial concentration of TC,dosage of TiO₂/PPy/NiCoP nanocomposites photocatalyst,pH value,ionic strength,active groups and reusability of the TiO₂/PPy/NiCoP photocatalyst on the photodegradation of TC were investigated.The possible photocatalytic mechanism was preliminarily analyzed.At room temperature and natural pH,the removal rate of 50 mL 10 mg/L TC by 20 mg TiO₂/PPy/NiCoP was 83.2%under 3 h illumination.The results showed that hole（h⁺）and superoxide radical（·O₂^-）were the main active groups in the process of photodegradation of TC by TiO₂/PPy/NiCoP photocatalyst.The degradation efficiency of TC with TiO₂/PPy/NiCoP decreased from 83.2%to 74.3%after 5 times of recycling,indicating the stability and reusability of TiO₂/PPy/NiCoP nano photocatalyst.The experimental results showed that the coexisting ions had little effect on the photocatalytic efficiency of TiO₂/PPy/NiCoP nano photocatalyst.The TiO₂/PPy/NiCoP nano photocatalyst had good catalytic effect in a wide pH range,which was expected to be applied to the efficient removal of TC in actual wastewater.（2）With large specific surface area,GO can be used as another vectors.A novel GO/NiCoP nano photocatalyst was fabricated by one-step chemical reduction method.SEM、TEM、XPS、XRD method were used to characterized the prepared GO/NiCoP nanocomposites.The effects of the ratio between GO and NiCoP,initial concentration of TC,dosage of GO/NiCoP nano photocatalyst,pH value,ionic strength,active groups and reusability of GO/NiCoP nano photocatalyst on degradation of TC were investigated.At room temperature and natural pH,the degradation efficiency of 50mL 10 mg/L TC by 50 mg of GO/NiCoP was 88.4%under 3 h illumination.The results show that·O₂^-were the main active groups in the process of photocatalytic degradation of TC by GO/NiCoP nanocomposites photocatalyst.The degradation efficiency of GO/NiCoP on TC decreased from 88.4%to 77.7%after 5 times of recycling,which indicated that the GO/NiCoP nano photocatalyst has good stability and reusability.The experimental results showed that the coexisting ions had little effect on the photocatalytic efficiency of GO/NiCoP nano photocatalyst.The GO/NiCoP nano photocatalyst had good catalytic effect in a wide pH range,which was expected to be applied to the efficient removal of TC in actual wastewater.（3）NH₂-MIL-101（Fe）@NiCoP nano photocatalyst with the metal organic framework（MOFs）as the carrier was prepared by hydrothermal method and one-step chemical reduction method.NH₂-MIL-101（Fe）@NiCoP was characterized by various analytical methods such as SEM、TEM、XPS and so on.The effects of reaction time,initial concentration of TC,dosage of NH₂-MIL-101（Fe）@NiCoP nano photocatalyst,pH value,ionic strength,active groups and reusability of NH₂-MIL-101（Fe）@NiCoP nano photocatalyst on degradation of TC were investigated.At room temperature and natural pH,the degradation efficiency of 50 mL 50 mg/L TC by 10 mg NH₂-MIL-101（Fe）@NiCoP was 90.1%under 2 h illumination.The results showed that h⁺and·O₂^-were the main active groups in the process of photocatalytic degradation of TC by NH₂-MIL-101（Fe）@NiCoP nano photocatalyst.The degradation efficiency of NH₂-MIL-101（Fe）@NiCoP on TC decreased from 90.1%to86.6%after 5 times of recycling,which indicated that NH₂-MIL-101（Fe）@NiCoP nano photocatalyst had good stability and reusability.The experimental results showed that the coexisting ions had no obvious effect on the photocatalytic efficiency of NH₂-MIL-101（Fe）@NiCoP.The NH₂-MIL-101（Fe）@NiCoP nano photocatalyst had good catalytic effect in a wide pH range,which was expected to be applied to the efficient removal of TC in actual wastewater.