Hierarchically porous titania xerogel monoliths: synthesis, characterization and electrochemical properties
Hierarchically porous titania xerogel monoliths: synthesis, characterization and electrochemical properties
复制标题
DOI：
10.1016/j.materresbull.2015.08.025
复制
发表时间：
2016
影响因子：
5.4
通讯作者：
Wenjun Zhu;Hui Yang;Xie Yuan;Sai Sun;Xingzhong Guo
中科院分区：
文献类型：
--
作者：
Wenjun Zhu;Hui Yang;Xie Yuan;Sai Sun;Xingzhong Guo
在甲酰胺（FA）和三嵌段共聚物F127存在的情况下，采用简单的溶胶-凝胶分离工艺，成功地合成了分层多孔二氧化钛（TiO2）干凝胶单体，然后进行常压干燥以去除溶剂。体系的凝胶化是由FA介导的，而F127增强了相分离。干燥后的干凝胶呈现出由大大孔和介孔骨架构成的分层多孔结构，其BET比表面积高达444 m2 - 1。在800℃下热处理，形成了具有高热稳定性的锐钛矿相，而不破坏宏观结构。制备的多孔tio2xero凝胶表现出优异的电化学性能，在1℃下循环100次后，tio2xero凝胶的比容量可保持在114 mAh g−1（69 mAh cm−3）以上，具有良好的循环稳定性。
Hierarchically porous titania (TiO2) xerogel monoliths were successfully synthesized by a facile sol–gel process accompanied by phase separation in the presence of formamide (FA) and triblock copolymer F127, followed by ambient pressure drying to remove the solvents. Gelation of the system has been mediated by FA, while F127 enhances a phase-separation. The resultant dried xerogel presents a hierarchically porous structure constructed by large macropores and mesoporous skeletons, which exhibits a high BET surface area of 444 m2g−1. Heat-treatment at 800 °C results in the formation of the crystalline anatase phase with high thermal stability, without spoiling the macrostructure. The as- prepared porous TiO2xerogel displays superior electrochemical properties, and the specific capacity of TiO2xerogel could remain over 114 mAh g−1(69 mAh cm−3) at 1 C after 100 cycles, representing a good cycling stability.