The Preparation And Modification Of Nano TiO₂ Photocatalyst

TiO₂ photocatalytic degradation technology can use solar energy to degrade pollutants.It has many advantages,like toxic harmless,mild reaction conditions,etc.,and it’s a very promising technology.However,TiO₂ can only absorb ultraviolet,the light energy utilization is not efficient.In this study,sol-gel process is used to synthesize TiO₂ particles.Ti（OBu）4 is used as raw material,and glacial acetic acid/acetyl acetone is used as inhibitor,various reaction conditions are studied and optimized.The results shows that when using glacial acetic acid as inhibitors,30℃ as hydrolysis temperature,and the molar ratio of glacial acetic acid: butyl titanate: water: ethanol is 0.5: 1: 4: 5,the performance of TiO₂ is best.Secondly,a dipping method is used to modify Ti O₂,and the process conditions were optimized.The results shows that when the concentration of cadmium nitrate/sodium sulfide solution is 1μmol / L,and immersion times is 5,the obtained CdS/ TiO₂ catalyst has best performance.Finally,the CdS/ TiO₂ catalyst obtained was characterized by measuring the load of CdS,and Rhodamine B was used as the target pollutant to investigate the performance of modified CdS/ TiO₂ catalyst& pure TiO₂.The results shows that the absorbing-range of modified TiO₂ is expanded and can absorb visible light.And modified CdS / TiO₂ catalyst also has better catalytic activity.After 110 minutes of lighting,a 98% degradation rate of 5mg/ L Rhodamine B can be reached.