Investigation On The Photocatalysis Of TiO₂/biomass Carbon Materials And Charge Transfer Of Electrode Interface

Bio-carbon materials are widely used in solar cells,supercapacitors,lithium-ion batteries and other fields because of their wide source,renewable and structural characteristics.TiO2 attracted much attention in the research field of photocatalysis due to its stable structure,non-toxic,low price,high photocatalytic degradation of organic pollutants ability,etc.In this paper,TiO2/C composites were prepared from tetratropyl titanate by using plane tree fluff(PTF)as carbon source.The photocatalytic properties of TiO2/C composites materials were studied by the degradation of methylene blue.The proportion of PTF and TiO2 in the samples influenced the photocatalystic performances.All the TiO2/C composites show better photocatalytic activity than Degussa P25,and the sample with 1:3 proportion of PTF and TiO2 has the highest photocatalytic activity.The ac impedance spectra of IB and VIB family metals(Cu,Ag,Au,Cr,Mo and W)in 1M Na2SO4 were also investigated by the electrochemical impedance spectroscopy technique.Charge transfer resistances(Rct)of the metals were obtained by simulation of the impedance spectra with Randle’s equivalent circuit.It is found that the charge transfer resistances of IB and VIB family metals display periodic properties.Metals with large standard electrode potentials show large charge transfer resistances.VIB family metals have larger charge transfer resistance than IB family metals.Simultaneously,for the better understanding on the electrode kinetics and the influence of various factors including temperature,cell voltage,stirring and electrode surface area and roughness on aluminum electrolysis the charge transfer process of graphite electrode in 1 M Na2SO4 was also investigated by the electrochemical impedance technique.Electrode surface area and roughness are controlled by adjusting electrode depth in electrolyte and polishing with sandpaper in different models.The impedance spectra were simulated with the Randle’s equivalent circuits.The dependence of charge transfer resistance on temperature,cell voltage,stirring rate,electrode surface area and roughness was clarified.Increasing the temperature,applied cell voltage and stirring are favor for reducing the charge transfer resistance of graphite electrode in 1 M Na2SO4.Graphite electrode in rough surface is of high reactivity and small charge transfer resistance and that with large surface is of great charge transfer resistance.