Study On Preparation And Properties Of The Ni-NiO/TiO₂ Hollow Tubular Porous Composites

In this study,TBOT was used as the titanium source to prepare Ti02 by sol-gel method.Then renewable lignocellulose was used as precursor,a rod-shaped nickel shell formed by electroless was used as a structural template to prepare the Ni-NiO/TiO2 hollow tubular composite.It was intended to improve the performance of TiO2 by semiconductor loading modification.Main conclusions of the study are as follows:(1)The calcination temperature,calcination time and the times of deposition of Ti02 and metallized cellulose were used as variables.Then the change of photocatalytic efficiency was looked as the indicator of investigation,RSM was used to optimize composite's preparation processes.The optimum preparation conditions of the Ni-NiO/TiO2 hollow tubular composite are as follows:calcination temperature is 600?,calcination time is 5 h,the times of deposition are 3.(2)Effect of preparation conditions on properties of Ni-NiO/TiO2 composites.The calcination temperature and calcination time were taken as single factor variables,respectively.And the degradation efficiency of MB and Pb(II)were taken as the standard.The conclusions show that there are three components in the sample including TiO2,Ni and NiO.With the increase of temperature,Anatase transformes to Rutile;the crystallites prepared at 600 C have the best development.However,the change in calcination time did not have a significantly affect on the crystal structure of TiO2.Compare with pure TiO2,the samples prepared in different conditions all have red shift and the response intensity also increases in the ultraviolet range.When the calcination temperature was used as the variable,the degradation efficiencies of MB and Pb(?)both appeare the highest value at 600 C:87.425%and 86.088%,respectively.On the other hand,when the calcination time as the variable,the degradation efficiencies of MB and Pb(?)both appeare the highest value at 5 h,are 88.356%and 85.059%,respectively.(3)In order to improve the photocatalytic and adsorption properties of the prepared materials,a dilute hydrochloric acid treatment was used to surface the composite to increase its specific surface area.When concentration of HC1 is 15%,the samples had the largest BET value and the smallest average pore size,which are 24.686m2/g and 13.560 nm,respectively;and they are higher than samples untreated by HCl.And the results of Ra of the samples are also bigger than samples untreated by HCl.In addition,the biggest degradation efficiency of MB is 95.126%,the strongest adsorption rate of Pb(II)is 89.054%,the results are bigger than the samples untreated by HCl.