Bismuth titanate based materials have wide potential applications in thefields of dielectrics,piezoelec trics,ferroelectrics,catalysis and energy storage.In this study,a two dimensional(2-D)layered H_(1.07)Ti_(1.73)O_...Bismuth titanate based materials have wide potential applications in thefields of dielectrics,piezoelec trics,ferroelectrics,catalysis and energy storage.In this study,a two dimensional(2-D)layered H_(1.07)Ti_(1.73)O_(4)·nH_(2)O(HTO)crystal was used as a precursor to prepare 2-D bismuth titanate oriented poly crystal nanocomposites using two kinds of Bi^(3+)sources.The chemical reaction mechanisms for the for mation of bismuth titanates are proposed,and the crystal structures and their conversions are also ident ified.The formation mechanism of the discontinuous-zone-axis is revealed.The obtained bismuth tita nates are oriented polycrystals constructed from the orientation nanocrystals.In the process of forming the oriented polycrystal,the zone axis of the bismuth titanates obtained under different reaction con ditions can vary even if the same reactants are used in the reaction.The certain topological correspon dences among the oriented polycrystal,the precursor,and the intermediate,as well as the formation of bismuth titanates with a discontinuous-zone-axis based on a topochemical mesocrystal conversion reac tion,were proposed.The special arrangement structure of the TiO6 octahedral layers accommodating in the HTO crystal is the main reason for the constant change of the zone axis of the bismuth titanate nano composite.However,based on the crystallographic investigation of the reaction mechanism involved in the formation process of construction of the bismuth titanate oriented polycrystal nanocomposite from the HTO crystal,it is found that the topochemical mesocrystal conversion reaction with a discontinuous zone-axis is different from the conventional topochemical reactions.This may be attributed to the combi nation of the HTO matrix and Bi^(3+).It is vital to study the controllable preparation of bismuth titanate based nanocomposites and further understand the topochemical reaction.展开更多
基金supported in part by the National Natural Science Foundation of China(No.21005003)the Natural Science Basic Research Plan in Shaanxi Province of China(2019JM-091)+2 种基金the Industrial Science and Technology Plan in Shaanxi Province of China(19JC002)the Doctoral Scientific Research Starting Foundation of Baoji University of Arts and Sciences(No.ZK2018059)Baoji University of Arts and Sciences Postgraduate Innovative Research Projects(YJSCX19ZC11).
文摘Bismuth titanate based materials have wide potential applications in thefields of dielectrics,piezoelec trics,ferroelectrics,catalysis and energy storage.In this study,a two dimensional(2-D)layered H_(1.07)Ti_(1.73)O_(4)·nH_(2)O(HTO)crystal was used as a precursor to prepare 2-D bismuth titanate oriented poly crystal nanocomposites using two kinds of Bi^(3+)sources.The chemical reaction mechanisms for the for mation of bismuth titanates are proposed,and the crystal structures and their conversions are also ident ified.The formation mechanism of the discontinuous-zone-axis is revealed.The obtained bismuth tita nates are oriented polycrystals constructed from the orientation nanocrystals.In the process of forming the oriented polycrystal,the zone axis of the bismuth titanates obtained under different reaction con ditions can vary even if the same reactants are used in the reaction.The certain topological correspon dences among the oriented polycrystal,the precursor,and the intermediate,as well as the formation of bismuth titanates with a discontinuous-zone-axis based on a topochemical mesocrystal conversion reac tion,were proposed.The special arrangement structure of the TiO6 octahedral layers accommodating in the HTO crystal is the main reason for the constant change of the zone axis of the bismuth titanate nano composite.However,based on the crystallographic investigation of the reaction mechanism involved in the formation process of construction of the bismuth titanate oriented polycrystal nanocomposite from the HTO crystal,it is found that the topochemical mesocrystal conversion reaction with a discontinuous zone-axis is different from the conventional topochemical reactions.This may be attributed to the combi nation of the HTO matrix and Bi^(3+).It is vital to study the controllable preparation of bismuth titanate based nanocomposites and further understand the topochemical reaction.
