Synthesis of hierarchical mesoporous Ln_(2)Ti_(2)O_(7)(Ln=Y,Tb-Yb)pyrochlores and uranyl sorption properties  

作　　者：Linggen Kong Inna Karatchevtseva Tao Wei Nicholas Scales 

机构地区：[1]Australian Nuclear Science and Technology Organisation,Lucas Heights NSW,2234,Australia

出　　处：《Journal of Materials Science & Technology》2022年第18期22-32,共11页材料科学技术（英文版）

摘　　要：Mesoporous structured metal oxides exhibit many active applications.However,the synthesis of crystalline metal oxides with a ternary composition while maintaining satisfactory pore features is challeng-ing.Typically,high temperatures are required which inhibit control of pore structure properties including surface area,pore volume,and pore size.Herein,the synthesis of ternary metal oxides Ln_(2)Ti_(2)O_(7)pos-sessing pyrochlore crystal structure is achieved using a novel technique which combines‘soft’and hard colloid templating strategies.The formed materials are of submicron size and composed of∼25-30 nm product‘building blocks’with good chemical and phase stability.The polycrystalline powders have a high specific surface area(up to 70 m^(2)·g^(-1))and pore volume(∼0.35 cm^(3)·g^(-1))which result in a good adsorp-tion capacity(U uptake closing to 60 mg·g^(-1)).Remarkably,the material exhibits a significant portion of mesopores(mainly 10-40 nm)which facilitate fast adsorption of the cations due to high accessibility.The synthetic methodology described herein produces highly homogenous powders and can be applied to other compositions and structures.

关 键 词：Porous ternary metal oxides Dual template synthesis Lanthanide titanate PYROCHLORE Uranium adsorption 

分 类 号：TQ424[化学工程]