Study On The Copper Titanium Phosphate Glasses With Different Compositions And The Derived Porous Materials

Porous titanium phosphate glass-ceramics not only have a large specific surface area and a large pore size,but also contain a skeleton consisting of special functional crystal phases.Therefore,they can be used as adsorption and catalytic materials.In this work,high-temperature melting-water quenching method was used to prepare copper-titanium phosphate glasses with different compositions.After heat treatment and acid treatment,porous materials with different properties were obtained.XRD,FTIR,DTA,SEM,TEM and N₂-sorption were used to characterize the samples,and the effect of porous materials on removing methylene blue from the aqueous solution was studied,and their adsorption and photocatalytic properties were discussed.The main research contents and conclusions are as follows:1.With the different additions of Fe2O3?0,2.5,5,7.5,10,12.5 mol%?,magnesium-copper-titanium phosphate basic glasses were prepared.With the increase of Fe2O3 content,the depolymerization tendency of the glass network increases,the viscosity decreases,and the crystallization tendency increases.The base glasses was heat treated and then acid treated with 1 mol·L^-11 HCl for 24 h to obtain porous materials.The samples prepared with 0?2.5 mol%of Fe2O3 maintained Mg2P2O7 as the main crystal phase as the heat-treated samples.The formation of new phase anatase TiO2 was found in the samples prepared with 5?12.5 mol%of Fe2O3.By prolonging the acid treatment time and increasing the concentration of hydrochloric acid,the specific surface area of the samples increased.Among them,the samples derived from the basic glass with 7.5 mol%Fe2O3 and acid-treatment for 72 h has the largest specific surface area,reaching 127 m²?g^-1.The porous material?mass of 1.0 g?was used to remove methylene blue(100 mL in volume and 5 mg?L^-1)in the solution under dark conditions,and the removal efficiency reached 89%at 2 h.2.Magnesium-copper-titanium phosphate basic glasses with different TiO2contents?15,19.05,22.73,26.09,29.17 mol%?were prepared.With the increase of TiO2,the integrity of the glass network structure increased and the crystallization tendency increased.The base glasses was heat treated and then treated with 3 mol·L^-1HCl for 24 h to obtain a porous material.When the TiO2 content was 15?29.17 mol%,the specific surface area of the prepared samples was 59?96 m²?g^-1,and they all contained newly formed Ti₂O₃?H₂PO₄?₂?2H₂O and TiO₂ crystal phases?anatase or rutile?.Fine porous material powder?300 mg?was used to remove methylene blue(100 mL,10 mg?L^-1)in solution.The samples from the glasses containing 26.09 and29.17 mol%of TiO2 showed removal efficiencies of 58%and 54%at 3 h in dark condition,and 96%under further UV irradiation for 4 h.3.xZnO·?40-x?CuO·30TiO2·30P2O5?x=0?40 mol%?basic glasses were prepared.With the addition of ZnO,the glass network structure becomed loose and the viscosity decreased,and while CuO promoted crystallization of the glass.The base glasses was heat-treated and then treated with 3 mol·L^-11 HCl for 24 h to obtain porous materials.The products had specific surface area of 55?72 m²?g^-1,and contained new crystal phase Ti₂O₃?H₂PO₄?₂?2H₂O and anatase TiO₂.The porous material?300 mg?was crushed and the fine powder was used to remove methylene blue(100 mL,10 mg?L^-1)in solution.The removal effiencies of the porous were 39%?63%in the dark condition for 3 h,and 88%?98%under further UV irradiation for 4 h.4.The porous samples derived from the glass containing with 26.09 and 29.17mol%of TiO2 and 0?40 mol%of ZnO were calcined at high temperature,and it was found that the porous skeleton collapsed and the Ti₂O₃?H₂PO₄?₂?2H₂O crystal phase decomposed.As a result,the removal efficiency of methylene blue in the solution by the calcined sample was reduced,and degradation of methylene blue became slow,suggesting the synergistic effect of the porous structure and the TiO₂ phase on the photocatalytic degradation of dye.