Preparation Of AgIO₃/BiOIO₃、ZrGeO₄ And CeHIO₆·4H₂O And Their Properties For Degradation Of Organic Dyes

Under the double crisis of energy shortage and environmental pollution,it is of great significance to develop catalysts that can be used for energy conservation of pollutants.Photocatalytic technology is an energy-saving technology that uses sunlight to degrade pollutants at room temperature.In this paper,a novel AgIO₃/BiOIO₃ composite compound was prepared.The performance of photocatalytic degradation of pollutants was studied by using organic dyes as model pollutants under visible light.At present,most photocatalysts have high photocatalytic performance and high chemical stability while having high solar light utilization efficiency.Therefore,to get rid of the dependence on light,it is another effective energy-saving way to treat pollutants by preparing low-temperature catalysts that can degrade pollutants at room temperature without heating.ZrGeO4 compounds and CeHIO6·4H2O compounds were prepared in this paper.Organic dyes were used as model pollutants to study their degradation properties.They exhibit high degradation properties and high stability to organic dyes in complete protection from light.The results of this paper are summarized as follows:（1）A series of composite compounds AgIO3/BiOIO3 with different AgIO3 doping amount were successfully prepared by hydrothermal method.Under visible light irradiation,AgIO₃/BiOIO3（Ag-Bi-5）with AgIO3 doping amount of 5%degraded rhodamine B（RhB）was higher than that of 1%,10%,and 15%.Through testing,it was found that the photocurrent response of the Ag-Bi-5 sample was strong.Therefore,it is considered that the sample has a low carrier recombination ratio,thereby exhibiting high photocatalytic activity.And after repeated use for 5 times,Ag-Bi-5 activity did not decrease.Finally,the main active species that play a role in dye degradation are explored.（2）ZrGeO₄ compounds were successfully prepared by hydrothermal method.It is a nanoparticle with a particle size of 10-20 nm and has a Scheelite-type crystal phase.The ZrGeO₄ sample showed higher degradation activity of Rhodamine B（RhB）and methylene blue（MB）at room temperature without light.After 3 cycles of use,its activity was not significantly reduced and its chemical composition did not change during the degradation experiment,and its activity was significantly higher than the previously reported activities of CeGeO4 and ZrHIO6·4H2O.Finally,the main active species that play a role in dye degradation are explored.（3）A new and highly efficient CeHIO6·4H2O compound was successfully prepared by a simple precipitation method.The CeHIO6·4H2O sample is essentially a yellow inorganic semiconductor with a particle size of 0.2-10μm,a band gap of 2.75 eV,a specific surface area of 1.52 m²·g^-1,and an amorphous structure.At room temperature and without light,CeHIO6·4H2O samples showed high activity in the degradation of RhB,methyl orange（MO）and MB,and their activity was significantly higher than previously reported ZrGeO4,Ce（IO₃）₄,CeGeO₄,ZrHIO₆·4H₂O and Ce doped MoO₃.After 3 cycles of use,there was no significant loss of activity,and the chemical composition of CeHIO₆·4H₂O did not change during the experiment.Finally,the main active species of dye degradation and related mechanisms were explored.The results of this study have reference significance for the energy-saving treatment of pollutants and the design and preparation of photocatalysts and catalysts oriented by this function.