Photocatalytic Properties And Preparation Of Nanocarbon Modified Bi₁₂O₁₇Cl₂ Composites

As a new type of semiconductor photocatalyst,Bi₁₂O₁₇Cl₂ has become a promising photocatalyst due to its special band structure and excellent photocatalytic performance.However,due to the rapid recombination rate of electron-hole pair,the photocatalytic efficiency of Bi₁₂O₁₇Cl₂ is reduced,so it is a trend to modify it.Therefore,using Bi₁₂O₁₇Cl₂ as a researched target,nano carbon modification was applied for improving its photocatalytic ability to obtain Bi₁₂O₁₇Cl₂ based photocatalysts with high activity.The specific contents of this study are as follows:?1?A new CNTs/Bi₁₂O₁₇Cl₂ composite photocatalyst was prepared.The CNTs material with a tube size of 20 nm was evenly distributed on the surface of Bi₁₂O₁₇Cl₂ nanosheets,which not only enhanced its absorption under visible light,but also showed a better separation effect of photogenerated electrons and holes.The results showed that CNTs/Bi₁₂O₁₇Cl₂-2 had the best photocatalytic activity when the content of CNTs was 11 mg.The reaction rate of Rh B degradation was significantly higher than that of other materials?g-C₃N₄and P25?Ti O₂??,reaching 5.133min^-1g^-1,about 3.2 times more than that of pure Bi₁₂O₁₇Cl₂.In addition,the CNTs/Bi₁₂O₁₇Cl₂-2 composite particles also have good circulation stability.Through the experiments of active species capture on the catalyst,we know that h⁺and·O₂^-were the main active components,and speculate the possible photocatalytic reaction mechanism.?2?A new type of G/Bi₁₂O₁₇Cl₂ composite photocatalyst was prepared.The photocatalytic activity for degrading Rh B was investigated.The experimental results showed that when the amount of G was 7.5 mg,the photocatalytic activity of G/Bi₁₂O₁₇Cl₂-2 was the highest,and the composite particles had the better photocatalytic performance.The reaction rate of Rh B degradation over G/Bi₁₂O₁₇Cl₂-2 was 5.333 min^-1g^-1,which was about 2.6times more than that of pure Bi₁₂O₁₇Cl₂.In addition,the prepared G/Bi₁₂O₁₇Cl₂-2 composite particles also have good cycle stability.Through the active species capture experiment,it is known that h⁺and·O₂^-play a major role in the photocatalytic process.Finally,according to the results of the experiment and the results of characterization,the possible photocatalytic reaction mechanism of G/Bi₁₂O₁₇Cl₂ composite is proposed.